id
stringlengths
9
14
submitter
stringlengths
1
56
authors
stringlengths
5
7.68k
title
stringlengths
3
299
comments
stringlengths
1
1.15k
journal-ref
stringlengths
9
298
doi
stringlengths
12
97
report-no
stringlengths
3
341
categories
stringclasses
869 values
license
stringclasses
9 values
orig_abstract
stringlengths
16
2.44k
versions
listlengths
1
39
update_date
stringlengths
10
10
authors_parsed
listlengths
1
565
abstract
stringlengths
13
2.44k
2011.04735
Enrico Bertuzzo Prof.
Enrico Bertuzzo and Marco Taoso
Probing light dark scalars with future experiments
25 pages, 2 appendices, 6 figures. v2: version accepted for publication. Several clarifications added, Figs. 3-5 modified to take into account the heaviest state decay length. Conclusions unchanged
JHEP 03 (2021) 272
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate a dark sector containing a pair of light non-degenerate scalar particles, with masses in the MeV-GeV range, coupled to the visible sector through heavier mediators. The heaviest dark state is long-lived, and its decays offer new testable signals. We analyze the prospects for detection with the proposed beam-dump facility SHiP, and the proposed LHC experiments FASER and MATHUSLA. Moreover, we consider bounds from the beam-dump experiment CHARM and from colliders (LEP, LHC and BaBar). We present our results both in terms of an effective field theory, where the heavy mediators have been integrated out, and of a simplified model containing a vector boson mediator, which can be heavy $\gtrsim\mathcal{O}(1)$ TeV, or light $\mathcal{O}(10)$ GeV. We show that future experiments can test large portions of the parameter space currently unexplored, and that they are complementary to future High-Luminosity LHC searches.
[ { "created": "Mon, 9 Nov 2020 20:23:36 GMT", "version": "v1" }, { "created": "Mon, 22 Feb 2021 18:44:25 GMT", "version": "v2" } ]
2022-05-17
[ [ "Bertuzzo", "Enrico", "" ], [ "Taoso", "Marco", "" ] ]
We investigate a dark sector containing a pair of light non-degenerate scalar particles, with masses in the MeV-GeV range, coupled to the visible sector through heavier mediators. The heaviest dark state is long-lived, and its decays offer new testable signals. We analyze the prospects for detection with the proposed beam-dump facility SHiP, and the proposed LHC experiments FASER and MATHUSLA. Moreover, we consider bounds from the beam-dump experiment CHARM and from colliders (LEP, LHC and BaBar). We present our results both in terms of an effective field theory, where the heavy mediators have been integrated out, and of a simplified model containing a vector boson mediator, which can be heavy $\gtrsim\mathcal{O}(1)$ TeV, or light $\mathcal{O}(10)$ GeV. We show that future experiments can test large portions of the parameter space currently unexplored, and that they are complementary to future High-Luminosity LHC searches.
2208.00793
Georgii Shestakov
N.N. Achasov, A.V. Kiselev, and G.N. Shestakov
Electroweak production of $\chi_{Q1}$ states in $e^+e^-$ collisions: A brief review
6 pages; v2: published version, corrections and clarifications made, new references and a paragraph on polarized electron beam added
Phys. Rev. D 106, 093012 (2022)
10.1103/PhysRevD.106.093012
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A brief review of the available experimental and theoretical results on the production of the $\chi_{Q1}$ states in $e^+e^-$ annihilation and photon-photon $\gamma\gamma^*$ interactions is presented. Future data on the production of the $\chi_{c1}(1P)$, $\chi_{c1}(3872)$, $\chi_{c1} (4140)$, $\chi_{c1}(4274)$, $\chi_{c1}(4685)$, $\chi_{b1} (1P)$, $\chi_{b1}(2P )$, and $\chi_{b1}(3P)$ resonances in $e^+e^-$ annihilation and $\gamma\gamma^*$ interactions will help the development and unification of theoretical predictions related to the electroweak decays of heavy quarkonia, the reduction of their spread and model uncertainties.
[ { "created": "Mon, 1 Aug 2022 12:09:35 GMT", "version": "v1" }, { "created": "Wed, 30 Nov 2022 16:09:19 GMT", "version": "v2" } ]
2022-12-14
[ [ "Achasov", "N. N.", "" ], [ "Kiselev", "A. V.", "" ], [ "Shestakov", "G. N.", "" ] ]
A brief review of the available experimental and theoretical results on the production of the $\chi_{Q1}$ states in $e^+e^-$ annihilation and photon-photon $\gamma\gamma^*$ interactions is presented. Future data on the production of the $\chi_{c1}(1P)$, $\chi_{c1}(3872)$, $\chi_{c1} (4140)$, $\chi_{c1}(4274)$, $\chi_{c1}(4685)$, $\chi_{b1} (1P)$, $\chi_{b1}(2P )$, and $\chi_{b1}(3P)$ resonances in $e^+e^-$ annihilation and $\gamma\gamma^*$ interactions will help the development and unification of theoretical predictions related to the electroweak decays of heavy quarkonia, the reduction of their spread and model uncertainties.
2112.01491
Julian Bollig
Julian Bollig and Stefan Vogl
Impact of bound states on non-thermal dark matter production
27 pages, 3 figures, 3 appendices, single column
JCAP 10 (2022) 031
10.1088/1475-7516/2022/10/031
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the impact of non-perturbative effects, namely Sommerfeld enhancement and bound state formation, on the cosmological production of non-thermal dark matter. For this purpose, we focus on a class of simplified models with t-channel mediators. These naturally combine the requirements for large corrections in the early Universe, i.e. beyond the Standard Model states with long range interactions, with a sizable new physics production cross section at the LHC. We find that the dark matter yield of the superWIMP mechanism is suppressed considerably due to the non-perturbative effects under consideration. This leads to a significant shift in the cosmologically preferred parameter space of non-thermal dark matter in these models. We also revisit the implications of LHC bounds on long-lived particles associated with non-thermal dark matter and find that testing this scenario at the LHC is a bigger challenge than previously anticipated.
[ { "created": "Thu, 2 Dec 2021 18:45:10 GMT", "version": "v1" }, { "created": "Mon, 13 Dec 2021 15:40:57 GMT", "version": "v2" }, { "created": "Fri, 22 Jul 2022 14:12:00 GMT", "version": "v3" }, { "created": "Tue, 26 Jul 2022 10:12:38 GMT", "version": "v4" }, { "created": "Wed, 12 Oct 2022 09:44:31 GMT", "version": "v5" } ]
2022-10-13
[ [ "Bollig", "Julian", "" ], [ "Vogl", "Stefan", "" ] ]
We explore the impact of non-perturbative effects, namely Sommerfeld enhancement and bound state formation, on the cosmological production of non-thermal dark matter. For this purpose, we focus on a class of simplified models with t-channel mediators. These naturally combine the requirements for large corrections in the early Universe, i.e. beyond the Standard Model states with long range interactions, with a sizable new physics production cross section at the LHC. We find that the dark matter yield of the superWIMP mechanism is suppressed considerably due to the non-perturbative effects under consideration. This leads to a significant shift in the cosmologically preferred parameter space of non-thermal dark matter in these models. We also revisit the implications of LHC bounds on long-lived particles associated with non-thermal dark matter and find that testing this scenario at the LHC is a bigger challenge than previously anticipated.
hep-ph/0409225
Srubabati Goswami
Srubabati Goswami, Raghavan Rangarajan, K. Agashe, A. Bandyopadhyay, K. Bhattacharya, B. Brahmachari, C. Burgess, E.J. Chun, D. Choudhury, P.K.Das, A. Dighe, R. Godbole, N. Gupta, M. Kaplinghat, D. Indumathi, J. Forshaw, Y.Y. Keum, B. Layek, D. Majumdar, N. Mahajan, P. Mehta, R.N. Mohapatra, N. Mondal, S. More, Y. Nir, S. Pakvasa, M.K. Parida, M. Ravikumar, G. Rajasekaran, P. Ramadevi, S.D. Rindani, D.P. Roy, P. Roy, N. Sahu, A. Samanta, Y. Shadmi, A.M. Srivastava, S. Uma Sankar, R. Vaidya, U. Yajnik
Working Group Report: Neutrino and Astroparticle Physics
Prepared for the 8th Workshop on High-Energy Physics Phenomenology (WHEPP-8), IIT Mumbai, India, 5-16 Jan 2004
Pramana63:1391-1406,2004
10.1007/BF02704904
null
hep-ph
null
This is the report of neutrino and astroparticle physics working group at WHEPP-8. We present the discussions carried out during the workshop on selected topics in the above fields and also indicate progress made subsequently. The neutrino physics subgroup studied the possibilites of constraining neutrino masses, mixing and CPT violation in lepton sector from future experiments. Neutrino mass models in the context of abelian horizontal symmetries, warped extra dimensions and in presence of triplet Higgs were studied. Effect of threshold corrections on radiative magnification of mixing angles was investigated. The astroparticle physics subgroup focused on how various particle physics inputs affect the CMBR fluctuation spectrum, and on brane cosmology. This report also contains an introduction on how to use the publicly available code CMBFAST to calculate the CMBR fluctuations.
[ { "created": "Sun, 19 Sep 2004 14:12:17 GMT", "version": "v1" } ]
2008-11-26
[ [ "Goswami", "Srubabati", "" ], [ "Rangarajan", "Raghavan", "" ], [ "Agashe", "K.", "" ], [ "Bandyopadhyay", "A.", "" ], [ "Bhattacharya", "K.", "" ], [ "Brahmachari", "B.", "" ], [ "Burgess", "C.", "" ], [ "Chun", "E. J.", "" ], [ "Choudhury", "D.", "" ], [ "Das", "P. K.", "" ], [ "Dighe", "A.", "" ], [ "Godbole", "R.", "" ], [ "Gupta", "N.", "" ], [ "Kaplinghat", "M.", "" ], [ "Indumathi", "D.", "" ], [ "Forshaw", "J.", "" ], [ "Keum", "Y. Y.", "" ], [ "Layek", "B.", "" ], [ "Majumdar", "D.", "" ], [ "Mahajan", "N.", "" ], [ "Mehta", "P.", "" ], [ "Mohapatra", "R. N.", "" ], [ "Mondal", "N.", "" ], [ "More", "S.", "" ], [ "Nir", "Y.", "" ], [ "Pakvasa", "S.", "" ], [ "Parida", "M. K.", "" ], [ "Ravikumar", "M.", "" ], [ "Rajasekaran", "G.", "" ], [ "Ramadevi", "P.", "" ], [ "Rindani", "S. D.", "" ], [ "Roy", "D. P.", "" ], [ "Roy", "P.", "" ], [ "Sahu", "N.", "" ], [ "Samanta", "A.", "" ], [ "Shadmi", "Y.", "" ], [ "Srivastava", "A. M.", "" ], [ "Sankar", "S. Uma", "" ], [ "Vaidya", "R.", "" ], [ "Yajnik", "U.", "" ] ]
This is the report of neutrino and astroparticle physics working group at WHEPP-8. We present the discussions carried out during the workshop on selected topics in the above fields and also indicate progress made subsequently. The neutrino physics subgroup studied the possibilites of constraining neutrino masses, mixing and CPT violation in lepton sector from future experiments. Neutrino mass models in the context of abelian horizontal symmetries, warped extra dimensions and in presence of triplet Higgs were studied. Effect of threshold corrections on radiative magnification of mixing angles was investigated. The astroparticle physics subgroup focused on how various particle physics inputs affect the CMBR fluctuation spectrum, and on brane cosmology. This report also contains an introduction on how to use the publicly available code CMBFAST to calculate the CMBR fluctuations.
2310.15159
Fanyi Zhao
Zhong-Bo Kang, Kyle Lee, Ding Yu Shao, Fanyi Zhao
Probing Transverse Momentum Dependent Structures with Azimuthal Dependence of Energy Correlators
36 pages, 7 figures
JHEP 03, 153 (2024)
10.1007/JHEP03(2024)153
MIT-CTP/5632
hep-ph hep-ex nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
We study the azimuthal angle dependence of the energy-energy correlators $\langle \mathcal{E}(\hat{n}_1)\mathcal{E}(\hat{n}_2)\rangle$ in the back-to-back region for $e^+e^-$ annihilation and deep inelastic scattering (DIS) processes with general polarization of the proton beam. We demonstrate that the polarization information of the beam and the underlying partons from the hard scattering is propagated into the azimuthal angle dependence of the energy-energy correlators. In the process, we define the Collins-type EEC jet functions and introduce a new EEC observable using the lab-frame angles in the DIS process. Furthermore, we extend our formalism to explore the two-point energy correlation between hadrons with different quantum numbers $\mathbb{S}_i$ in the back-to-back limit $\langle \mathcal{E}_{\mathbb{S}_1}(\hat{n}_1)\mathcal{E}_{\mathbb{S}_2}(\hat{n}_2)\rangle$. We find that in the Operator Product Expansion (OPE) region the nonperturbative information is entirely encapsulated by a single number. Using our formalism, we present several phenomenological studies that showcase how energy correlators can be used to probe transverse momentum dependent structures.
[ { "created": "Mon, 23 Oct 2023 17:57:23 GMT", "version": "v1" } ]
2024-06-06
[ [ "Kang", "Zhong-Bo", "" ], [ "Lee", "Kyle", "" ], [ "Shao", "Ding Yu", "" ], [ "Zhao", "Fanyi", "" ] ]
We study the azimuthal angle dependence of the energy-energy correlators $\langle \mathcal{E}(\hat{n}_1)\mathcal{E}(\hat{n}_2)\rangle$ in the back-to-back region for $e^+e^-$ annihilation and deep inelastic scattering (DIS) processes with general polarization of the proton beam. We demonstrate that the polarization information of the beam and the underlying partons from the hard scattering is propagated into the azimuthal angle dependence of the energy-energy correlators. In the process, we define the Collins-type EEC jet functions and introduce a new EEC observable using the lab-frame angles in the DIS process. Furthermore, we extend our formalism to explore the two-point energy correlation between hadrons with different quantum numbers $\mathbb{S}_i$ in the back-to-back limit $\langle \mathcal{E}_{\mathbb{S}_1}(\hat{n}_1)\mathcal{E}_{\mathbb{S}_2}(\hat{n}_2)\rangle$. We find that in the Operator Product Expansion (OPE) region the nonperturbative information is entirely encapsulated by a single number. Using our formalism, we present several phenomenological studies that showcase how energy correlators can be used to probe transverse momentum dependent structures.
hep-ph/0311350
Gevorg Bunatian
G. G. Bunatian (Joint Institute for Nuclear Research, Dubna, Russia)
Radiative Corrections to the Neutron Beta-decay within the Standard Model
REVTEX, 50 pages, no figures, uses the auxiliary axodrow.sty
null
null
E4-2003-206
hep-ph
null
Starting with the basic Lagrangian of the Standard Model, the radiative corrections to the neutron beta-decay are acquired. The electroweak interactions are consistently taken into consideration amenably to the Weinberg-Salam theory. The effect of the strong quark-quark interactions on the neutron beta-decay is parameterized by introducing the nucleon electromagnetic form factors and the nucleon weak transition current specified by the form factors g_V, g_A, ... The radiative corrections to the total decay probability W and to the asymmetry coefficient of the electron momentum distribution A obtained to constitute \delta W = 8.7%, \delta A = -2% . The contribution to the radiative corrections due to allowance for the nucleon form factors and the nucleon exited states amounts up to a few per cent to the whole value of the radiative corrections. The ambiguity in description of the nucleon compositeness is this surely what causes the uncertainties ~0.1% in evaluation of the neutron beta-decay characteristics. For now, this puts bounds to the precision attainable in obtaining the element V_ud of the CKM matrix and the g_V, g_A, ... values from experimental data processing.
[ { "created": "Wed, 26 Nov 2003 22:26:37 GMT", "version": "v1" } ]
2016-09-06
[ [ "Bunatian", "G. G.", "", "Joint Institute for Nuclear Research, Dubna, Russia" ] ]
Starting with the basic Lagrangian of the Standard Model, the radiative corrections to the neutron beta-decay are acquired. The electroweak interactions are consistently taken into consideration amenably to the Weinberg-Salam theory. The effect of the strong quark-quark interactions on the neutron beta-decay is parameterized by introducing the nucleon electromagnetic form factors and the nucleon weak transition current specified by the form factors g_V, g_A, ... The radiative corrections to the total decay probability W and to the asymmetry coefficient of the electron momentum distribution A obtained to constitute \delta W = 8.7%, \delta A = -2% . The contribution to the radiative corrections due to allowance for the nucleon form factors and the nucleon exited states amounts up to a few per cent to the whole value of the radiative corrections. The ambiguity in description of the nucleon compositeness is this surely what causes the uncertainties ~0.1% in evaluation of the neutron beta-decay characteristics. For now, this puts bounds to the precision attainable in obtaining the element V_ud of the CKM matrix and the g_V, g_A, ... values from experimental data processing.
hep-ph/0501258
Daniel de Florian
Daniel de Florian and Werner Vogelsang
Threshold Resummation for the Inclusive-Hadron Cross-Section in pp Collisions
20 pages, 6 eps figures included
Phys.Rev. D71 (2005) 114004
10.1103/PhysRevD.71.114004
BNL-NT-04/41, RBRC-482
hep-ph
null
We study the resummation of large logarithmic perturbative corrections to the partonic cross sections relevant for the process pp->h X at high transverse momentum of the hadron h. These corrections arise near the threshold for the partonic reaction and are associated with soft-gluon emission. We perform the resummation to next-to-leading logarithmic accuracy. We present numerical results for the fixed-target regime and find enhancements over the next-to-leading order cross section, which significantly improve the agreement between theoretical predictions and data. We also apply the resummation for RHIC kinematics and find that subleading terms appear to play a rather important role here.
[ { "created": "Thu, 27 Jan 2005 13:55:26 GMT", "version": "v1" } ]
2009-11-11
[ [ "de Florian", "Daniel", "" ], [ "Vogelsang", "Werner", "" ] ]
We study the resummation of large logarithmic perturbative corrections to the partonic cross sections relevant for the process pp->h X at high transverse momentum of the hadron h. These corrections arise near the threshold for the partonic reaction and are associated with soft-gluon emission. We perform the resummation to next-to-leading logarithmic accuracy. We present numerical results for the fixed-target regime and find enhancements over the next-to-leading order cross section, which significantly improve the agreement between theoretical predictions and data. We also apply the resummation for RHIC kinematics and find that subleading terms appear to play a rather important role here.
1810.13384
Nikolaos Mavromatos
Thomas Bossingham, Nick E. Mavromatos and Sarben Sarkar
The role of temperature dependent string-inspired CPT violating backgrounds in leptogenesis and the chiral magnetic effect
17 pages revtex
null
10.1140/epjc/s10052-019-6564-3
KCL-PH-TH/2018-62
hep-ph gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a temperature dependent CPT-Violating (CPTV) axial time-like background (induced by the Kalb-Ramond tensor field of string theory) we discuss leptogenesis by solving the Boltzmann equation.The current work non-trivially modifies the framework of a previous phenomenological approach by the authors where the CPTV axial background was considered to be a constant (with no microscopic justification). The constant background approximation though is shown to capture the main phenomenological features of leptogenesis. On comparing our analysis to the related chiral magnetic effect for axial current condensates, we conclude that the Kalb-Ramond field does not play the role of the chiral chemical potential needed for that effect.
[ { "created": "Wed, 31 Oct 2018 16:30:02 GMT", "version": "v1" } ]
2019-02-20
[ [ "Bossingham", "Thomas", "" ], [ "Mavromatos", "Nick E.", "" ], [ "Sarkar", "Sarben", "" ] ]
In a temperature dependent CPT-Violating (CPTV) axial time-like background (induced by the Kalb-Ramond tensor field of string theory) we discuss leptogenesis by solving the Boltzmann equation.The current work non-trivially modifies the framework of a previous phenomenological approach by the authors where the CPTV axial background was considered to be a constant (with no microscopic justification). The constant background approximation though is shown to capture the main phenomenological features of leptogenesis. On comparing our analysis to the related chiral magnetic effect for axial current condensates, we conclude that the Kalb-Ramond field does not play the role of the chiral chemical potential needed for that effect.
hep-ph/0003308
null
T. I. Belova, V. A. Gani, A. E. Kudryavtsev
On decay of large amplitude bubble of disoriented chiral condensate
6 pages, LaTeX, 5 PostScript figures
Phys. Atom. Nucl. 64, 140 (2001); [Russian version: Yad. Fiz. 64, 143 (2001)]
10.1134/1.1344952
ITEP-11/00
hep-ph hep-th
null
The time evolution of initially formed large amplitude bubble of disoriented chiral condensate (DCC) is studied. It is found that the evolution of this object may have a relatively long pre-decay stage. Simple explanation of such delay of the DCC bubble decay is given. This delay is related to the existence of the approximate solutions of multi-soliton type of the corresponding radial sine-Gordon equation in (3+1) dimensions at large bubble radius.
[ { "created": "Fri, 31 Mar 2000 06:18:02 GMT", "version": "v1" } ]
2017-01-04
[ [ "Belova", "T. I.", "" ], [ "Gani", "V. A.", "" ], [ "Kudryavtsev", "A. E.", "" ] ]
The time evolution of initially formed large amplitude bubble of disoriented chiral condensate (DCC) is studied. It is found that the evolution of this object may have a relatively long pre-decay stage. Simple explanation of such delay of the DCC bubble decay is given. This delay is related to the existence of the approximate solutions of multi-soliton type of the corresponding radial sine-Gordon equation in (3+1) dimensions at large bubble radius.
hep-ph/0309152
Ilja Dorsner
S.M. Barr (Bartol Research Institute)
A different see-saw formula for neutrino masses
12 pages, 2 figures
Phys.Rev.Lett.92:101601,2004
10.1103/PhysRevLett.92.101601
null
hep-ph
null
In a wide class of unified models there is an additional (and possibly dominant) term in the neutrino mass formula that under the simplest assumption takes the form M_{\nu} = (M_N + M_N^T)u/M_G, where M_N is the neutrino Dirac mass matrix, and u = O(M_W). This makes possible highly predictive models. A generalization of this form yields realistic neutrino masses and mixings more readily than the usual see-saw formula in some models.
[ { "created": "Fri, 12 Sep 2003 22:36:56 GMT", "version": "v1" } ]
2011-05-12
[ [ "Barr", "S. M.", "", "Bartol Research Institute" ] ]
In a wide class of unified models there is an additional (and possibly dominant) term in the neutrino mass formula that under the simplest assumption takes the form M_{\nu} = (M_N + M_N^T)u/M_G, where M_N is the neutrino Dirac mass matrix, and u = O(M_W). This makes possible highly predictive models. A generalization of this form yields realistic neutrino masses and mixings more readily than the usual see-saw formula in some models.
2304.09194
Tao Xu
Thomas C. Gehrman, Barmak Shams Es Haghi, Kuver Sinha, Tao Xu
The Primordial Black Holes that Disappeared: Connections to Dark Matter and MHz-GHz Gravitational Waves
23 pages + references, 8 figures; v2: added references, version published in JCAP
JCAP 10 (2023) 001
10.1088/1475-7516/2023/10/001
UTWI-10-2023
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the post-LIGO era, there has been a lot of focus on primordial black holes (PBHs) heavier than $\sim 10^{15}$g as potential dark matter (DM) candidates. We point out that the branch of the PBH family that disappeared - PBHs lighter than $\sim 10^9$g that ostensibly Hawking evaporated away in the early Universe - also constitute an interesting frontier for DM physics. Hawking evaporation itself serves as a portal through which such PBHs can illuminate new physics, for example by emitting dark sector particles. Taking a simple DM scalar singlet model as a template, we compute the abundance and mass of PBHs that could have provided, by Hawking evaporation, the correct DM relic density. We consider two classes of such PBHs: those originating from curvature perturbations generated by inflation, and those originating from false vacuum collapse during a first-order phase transition. For PBHs of both origins we compute the gravitational wave (GW) signals emanating from their formation stage: from second-order effects in the case of curvature perturbations, and from sound waves in the case of phase transitions. The GW signals have peak frequencies in the MHz-GHz range typical of such light PBHs. We compute the strength of such GWs compatible with the observed DM relic density, and find that the GW signal morphology can in principle allow one to distinguish between the two PBH formation histories.
[ { "created": "Tue, 18 Apr 2023 18:00:01 GMT", "version": "v1" }, { "created": "Fri, 13 Oct 2023 02:59:47 GMT", "version": "v2" } ]
2023-10-16
[ [ "Gehrman", "Thomas C.", "" ], [ "Haghi", "Barmak Shams Es", "" ], [ "Sinha", "Kuver", "" ], [ "Xu", "Tao", "" ] ]
In the post-LIGO era, there has been a lot of focus on primordial black holes (PBHs) heavier than $\sim 10^{15}$g as potential dark matter (DM) candidates. We point out that the branch of the PBH family that disappeared - PBHs lighter than $\sim 10^9$g that ostensibly Hawking evaporated away in the early Universe - also constitute an interesting frontier for DM physics. Hawking evaporation itself serves as a portal through which such PBHs can illuminate new physics, for example by emitting dark sector particles. Taking a simple DM scalar singlet model as a template, we compute the abundance and mass of PBHs that could have provided, by Hawking evaporation, the correct DM relic density. We consider two classes of such PBHs: those originating from curvature perturbations generated by inflation, and those originating from false vacuum collapse during a first-order phase transition. For PBHs of both origins we compute the gravitational wave (GW) signals emanating from their formation stage: from second-order effects in the case of curvature perturbations, and from sound waves in the case of phase transitions. The GW signals have peak frequencies in the MHz-GHz range typical of such light PBHs. We compute the strength of such GWs compatible with the observed DM relic density, and find that the GW signal morphology can in principle allow one to distinguish between the two PBH formation histories.
1907.06864
J.D. Vergados
J.D. Vergados (Physics Department University of Ioannina, Ioannina, Greece)
Searching for light WIMPS in view of neutron decay to dark matter
10 pages, 5 figures, 1 table. J. Phys. G: Nucl. Part. Phys (2020). arXiv admin note: substantial text overlap with arXiv:1812.08015
null
10.1088/1361-6471/ab326d
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the present work we examine the implications on dark matter searches of the possibility of a partial decay of a neutron into a dark matter particle, slightly lighter than itself. Such a scenario recently proposed is required to bridge the discrepancy between the results of two different experiments measuring the life time of the neutron. It was subsequently suggested that this light dark matter candidate could make up the whole of dark matter in the universe. We thus first compute the nucleon cross section based on such models. Then we proceed explore the various signatures appearing in dark matter searches involving nuclear targets, in the case of such a light dark matter candidate.
[ { "created": "Tue, 16 Jul 2019 06:57:45 GMT", "version": "v1" }, { "created": "Wed, 13 May 2020 07:56:26 GMT", "version": "v2" } ]
2020-05-15
[ [ "Vergados", "J. D.", "", "Physics Department University of Ioannina, Ioannina,\n Greece" ] ]
In the present work we examine the implications on dark matter searches of the possibility of a partial decay of a neutron into a dark matter particle, slightly lighter than itself. Such a scenario recently proposed is required to bridge the discrepancy between the results of two different experiments measuring the life time of the neutron. It was subsequently suggested that this light dark matter candidate could make up the whole of dark matter in the universe. We thus first compute the nucleon cross section based on such models. Then we proceed explore the various signatures appearing in dark matter searches involving nuclear targets, in the case of such a light dark matter candidate.
hep-ph/0701114
Jose Rodriguez-Quintero
Ph. Boucaud, J.P. Leroy, A. Le Yaouanc, J. Micheli, O. P\`ene, A.Y. Lokhov, J. Rodr\'iguez-Quintero, C. Roiesnel
Constraints on the IR behaviour of gluon and ghost propagator from Ward-Slavnov-Taylor identities
5 pages, 2 figures
Eur.Phys.J.A31:750-753,2007
10.1140/epja/i2006-10295-1
null
hep-ph
null
We consider the constraints of the Slavnov-Taylor identity of the IR behaviour of gluon and ghost propagators and their compatibility with solutions of the ghost Dyson-Schwinger equation and with the lattice picture.
[ { "created": "Mon, 15 Jan 2007 18:10:36 GMT", "version": "v1" } ]
2016-08-14
[ [ "Boucaud", "Ph.", "" ], [ "Leroy", "J. P.", "" ], [ "Yaouanc", "A. Le", "" ], [ "Micheli", "J.", "" ], [ "Pène", "O.", "" ], [ "Lokhov", "A. Y.", "" ], [ "Rodríguez-Quintero", "J.", "" ], [ "Roiesnel", "C.", "" ] ]
We consider the constraints of the Slavnov-Taylor identity of the IR behaviour of gluon and ghost propagators and their compatibility with solutions of the ghost Dyson-Schwinger equation and with the lattice picture.
2206.07641
Fernando Iguaz\'u Ram\'irez-Zavaleta
J. Montano-Dominguez, B. Quezadas-Vivian, F. Ramirez-Zavaleta, E. S. Tututi
Weak dipole moments of heavy fermions with flavor violation induced by $Z^\prime$ gauge bosons
25 pages, 7 figures
J.Phys.G 49 (2022) 7, 075004
10.1088/1361-6471/ac69ff
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A calculation of weak dipole moments of charged fermions of the Standard Model (SM) at the one-loop level, in the context of a general effective extended neutral current model with flavor changing $Z^\prime f_i \bar{f}_j$ vertices, is presented. We give numerical predictions for the anomalous weak magnetic dipole moment (AWMDM) $a^w_{fi}$, and the weak electric dipole moment (WEDM) $d^w_{f_i}$, for the $\tau$ lepton and $t$ quark. For several $Z^\prime$ gauge bosons considered, we find that, for the $\tau$ lepton, the best prediction for the real part of $a^w_{\tau}$ is of the order of $10^{-9}$, while the imaginary part is four orders of magnitude below. The highest value for the WEDM, $d^w_{\tau}$, corresponds to $10^{-26}$ $e$-cm, for its real part, and the imaginary part is three orders of magnitude below. On the other hand, we found for the top quark, that the best prediction for the real part of $a^w_t$ is of the order of $10^{-7}$ and its imaginary part is of the order of $10^{-11}$. We also found that $d^w_t$ is of the order of $10^{-26}$ $e$-cm for its real part, and its imaginary part can be as high as $10^{-31}$ $e$-cm.
[ { "created": "Wed, 15 Jun 2022 16:40:27 GMT", "version": "v1" } ]
2022-06-16
[ [ "Montano-Dominguez", "J.", "" ], [ "Quezadas-Vivian", "B.", "" ], [ "Ramirez-Zavaleta", "F.", "" ], [ "Tututi", "E. S.", "" ] ]
A calculation of weak dipole moments of charged fermions of the Standard Model (SM) at the one-loop level, in the context of a general effective extended neutral current model with flavor changing $Z^\prime f_i \bar{f}_j$ vertices, is presented. We give numerical predictions for the anomalous weak magnetic dipole moment (AWMDM) $a^w_{fi}$, and the weak electric dipole moment (WEDM) $d^w_{f_i}$, for the $\tau$ lepton and $t$ quark. For several $Z^\prime$ gauge bosons considered, we find that, for the $\tau$ lepton, the best prediction for the real part of $a^w_{\tau}$ is of the order of $10^{-9}$, while the imaginary part is four orders of magnitude below. The highest value for the WEDM, $d^w_{\tau}$, corresponds to $10^{-26}$ $e$-cm, for its real part, and the imaginary part is three orders of magnitude below. On the other hand, we found for the top quark, that the best prediction for the real part of $a^w_t$ is of the order of $10^{-7}$ and its imaginary part is of the order of $10^{-11}$. We also found that $d^w_t$ is of the order of $10^{-26}$ $e$-cm for its real part, and its imaginary part can be as high as $10^{-31}$ $e$-cm.
hep-ph/9407358
Mukhopadhyaya Biswarup
Rathin Adhikari and Biswarup Mukhopadhyaya
Scalar three-body decays and signals for new physics
11 pages, latex, MRI-PHY/8/94
Mod.Phys.Lett. A9 (1994) 3741-3748
10.1142/S0217732394003592
null
hep-ph
null
If massive invisible particles are pair-produced in a three-body decay, then the energy distribution of the other (visible) product is sensitive to the mass of the invisible pair. We use this fact in the context of a Higgs boson decaying into (i)a Z-boson and two massive neutrinos of a fourth generation, and (ii)a Z and two lightest particles in the minimal supersymmetric standard model. We discuss how the Z-energy spectrum in each case can reflect the values of the parameters in such models. (3 figures, hard copies available from authers on request).
[ { "created": "Fri, 22 Jul 1994 13:44:56 GMT", "version": "v1" } ]
2015-06-25
[ [ "Adhikari", "Rathin", "" ], [ "Mukhopadhyaya", "Biswarup", "" ] ]
If massive invisible particles are pair-produced in a three-body decay, then the energy distribution of the other (visible) product is sensitive to the mass of the invisible pair. We use this fact in the context of a Higgs boson decaying into (i)a Z-boson and two massive neutrinos of a fourth generation, and (ii)a Z and two lightest particles in the minimal supersymmetric standard model. We discuss how the Z-energy spectrum in each case can reflect the values of the parameters in such models. (3 figures, hard copies available from authers on request).
hep-ph/9708480
Dmitrij Shirkov
D.V. Shirkov
On the Analytic "Causal" Model for the QCD Running Coupling
4 pages, LaTex with psfig.sty, 2 PostScript figures
Nucl.Phys.Proc.Suppl. 64 (1998) 106-109
10.1016/S0920-5632(97)01044-X
null
hep-ph
null
We discuss the model $\bar{\alpha}_{an}(Q^2)$ recently proposed for the QCD running coupling $\bar{\alpha}_s(Q^2)$ in the Euclidean domain on the basis of the "asymptotic-freedom" expression and on causality condition in the form of the $Q^2$-analyticity. The model contains no adjustable parameters and obeys the important features: (i) Finite ghost-free behavior in the "low $Q^2$" region and correspondence with the standard RG-summed UV expressions;%\item~ % (ii) The universal limiting value $\bar{\alpha}_{an}(0)$ expressed only via group symmetry factors. This value as well as the $\bar{\alpha}_{an}$ behavior in the whole IR region $Q^2 \leq \Lambda^2$ turns out to be stable with respect to higher loop corrections; %\item~ (iii) Coherence between observed $\bar{\alpha}_s(M_{\tau}^2)$ value and integral information on the IR $\bar{\alpha}_s(Q^2)$ behavior extracted from jet physics.
[ { "created": "Thu, 28 Aug 1997 08:09:28 GMT", "version": "v1" } ]
2009-10-30
[ [ "Shirkov", "D. V.", "" ] ]
We discuss the model $\bar{\alpha}_{an}(Q^2)$ recently proposed for the QCD running coupling $\bar{\alpha}_s(Q^2)$ in the Euclidean domain on the basis of the "asymptotic-freedom" expression and on causality condition in the form of the $Q^2$-analyticity. The model contains no adjustable parameters and obeys the important features: (i) Finite ghost-free behavior in the "low $Q^2$" region and correspondence with the standard RG-summed UV expressions;%\item~ % (ii) The universal limiting value $\bar{\alpha}_{an}(0)$ expressed only via group symmetry factors. This value as well as the $\bar{\alpha}_{an}$ behavior in the whole IR region $Q^2 \leq \Lambda^2$ turns out to be stable with respect to higher loop corrections; %\item~ (iii) Coherence between observed $\bar{\alpha}_s(M_{\tau}^2)$ value and integral information on the IR $\bar{\alpha}_s(Q^2)$ behavior extracted from jet physics.
hep-ph/0412318
Oleg Lebedev
Wilfried Buchmuller, Koichi Hamaguchi, Oleg Lebedev, Michael Ratz
Dual Models of Gauge Unification in Various Dimensions
20 pages
Nucl.Phys.B712:139-156,2005
10.1016/j.nuclphysb.2005.01.038
DESY 04-237
hep-ph hep-th
null
We construct a compactification of the heterotic string on an orbifold T^6/Z_6 leading to the standard model spectrum plus vector--like matter. The standard model gauge group is obtained as an intersection of three SO(10) subgroups of E_8. Three families of SO(10) 16-plets are localized at three equivalent fixed points. Gauge coupling unification favours existence of an intermediate GUT which can have any dimension between five and ten. Various GUT gauge groups occur. For example, in six dimensions one can have E_6 \times SU(3), SU(4) \times SU(4) \times U(1)^2 or SO(8) \times SO(8), depending on which of the compact dimensions are large. The different higher--dimensional GUTs are `dual' to each other. They represent different points in moduli space, with the same massless spectrum and ultraviolet completion.
[ { "created": "Tue, 21 Dec 2004 17:47:17 GMT", "version": "v1" } ]
2010-11-19
[ [ "Buchmuller", "Wilfried", "" ], [ "Hamaguchi", "Koichi", "" ], [ "Lebedev", "Oleg", "" ], [ "Ratz", "Michael", "" ] ]
We construct a compactification of the heterotic string on an orbifold T^6/Z_6 leading to the standard model spectrum plus vector--like matter. The standard model gauge group is obtained as an intersection of three SO(10) subgroups of E_8. Three families of SO(10) 16-plets are localized at three equivalent fixed points. Gauge coupling unification favours existence of an intermediate GUT which can have any dimension between five and ten. Various GUT gauge groups occur. For example, in six dimensions one can have E_6 \times SU(3), SU(4) \times SU(4) \times U(1)^2 or SO(8) \times SO(8), depending on which of the compact dimensions are large. The different higher--dimensional GUTs are `dual' to each other. They represent different points in moduli space, with the same massless spectrum and ultraviolet completion.
hep-ph/9903499
Bodenmueller
Harald Fritzsch and Zhi-zhong Xing
Nearly Degenerate Neutrino Masses and Nearly Decoupled Neutrino Oscillations
Latex 6 pages. Talk given at the 17th International Workshop on Weak Interactions and Neutrinos, Cape Town, South Africa, January 1999
null
null
LMU 04/99
hep-ph
null
We introduce a simple flavor symmetry breaking scheme, in which charged lepton masses have a strong hierarchy and neutrino masses are almost degenerate. It is possible to obtain a natural suppression of lepton flavor mixing between the 1st and 3rd families as well as the approximate decoupling of atmospheric and solar neutrino oscillations with nearly bi-maximal mixing factors. The similarity and difference between lepton and quark flavor mixing schemes are briefly discussed.
[ { "created": "Fri, 26 Mar 1999 08:28:08 GMT", "version": "v1" } ]
2007-05-23
[ [ "Fritzsch", "Harald", "" ], [ "Xing", "Zhi-zhong", "" ] ]
We introduce a simple flavor symmetry breaking scheme, in which charged lepton masses have a strong hierarchy and neutrino masses are almost degenerate. It is possible to obtain a natural suppression of lepton flavor mixing between the 1st and 3rd families as well as the approximate decoupling of atmospheric and solar neutrino oscillations with nearly bi-maximal mixing factors. The similarity and difference between lepton and quark flavor mixing schemes are briefly discussed.
2009.04479
Malwin Niehus
Malwin Niehus, Martin Hoferichter, Bastian Kubis and Jacobo Ruiz de Elvira
Two-loop analysis of the pion-mass dependence of the $\rho$ meson
20 pages, 5 figures; version published in PRL: Appendix E.1 and Bayesian information criterion added; Mathematica notebook with two-loop expressions included as supplementary material
Phys. Rev. Lett. 126, 102002 (2021)
10.1103/PhysRevLett.126.102002
INT-20-034
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Analyzing the pion-mass dependence of $\pi\pi$ scattering phase shifts beyond the low-energy region requires the unitarization of the amplitudes from chiral perturbation theory. In the two-flavor theory, unitarization via the inverse-amplitude method (IAM) can be justified from dispersion relations, which is therefore expected to provide reliable predictions for the pion-mass dependence of results from lattice QCD calculations. In this work, we provide compact analytic expression for the two-loop partial-wave amplitudes for $J=0,1,2$ required for the IAM at subleading order. To analyze the pion-mass dependence of recent lattice QCD results for the $P$-wave, we develop a fit strategy that for the first time allows us to perform stable two-loop IAM fits and assess the chiral convergence of the IAM approach. While the comparison of subsequent orders suggests a breakdown scale not much below the $\rho$ mass, a detailed understanding of the systematic uncertainties of lattice QCD data is critical to obtain acceptable fits, especially at larger pion masses.
[ { "created": "Wed, 9 Sep 2020 18:00:03 GMT", "version": "v1" }, { "created": "Mon, 15 Mar 2021 13:49:45 GMT", "version": "v2" } ]
2021-03-17
[ [ "Niehus", "Malwin", "" ], [ "Hoferichter", "Martin", "" ], [ "Kubis", "Bastian", "" ], [ "de Elvira", "Jacobo Ruiz", "" ] ]
Analyzing the pion-mass dependence of $\pi\pi$ scattering phase shifts beyond the low-energy region requires the unitarization of the amplitudes from chiral perturbation theory. In the two-flavor theory, unitarization via the inverse-amplitude method (IAM) can be justified from dispersion relations, which is therefore expected to provide reliable predictions for the pion-mass dependence of results from lattice QCD calculations. In this work, we provide compact analytic expression for the two-loop partial-wave amplitudes for $J=0,1,2$ required for the IAM at subleading order. To analyze the pion-mass dependence of recent lattice QCD results for the $P$-wave, we develop a fit strategy that for the first time allows us to perform stable two-loop IAM fits and assess the chiral convergence of the IAM approach. While the comparison of subsequent orders suggests a breakdown scale not much below the $\rho$ mass, a detailed understanding of the systematic uncertainties of lattice QCD data is critical to obtain acceptable fits, especially at larger pion masses.
1906.06468
Pragyan Phukan
P. Phukan, M. Lalune and J. K. Sarma
Small $x$ phenomenology on gluon evolution through BFKL equation in light of a constraint in multi-Regge kinematics
null
null
10.1088/1572-9494/ab61ee
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We investigate the impact of so called kinematic constraint on gluon evolution at small $x$. Implanting the constraint on the real emission term of gluon ladder diagram, we obtain an integro-differential form of BFKL equation. Later we solve the equation analytically using the method of characteristics. We sketch the Bjorken x and transverse momentum $k_t^2$ dependence of our solution of unintegrated gluon distributions $f(x,k_t^2)$ in kinematic constraint supplemented BFKL equation and contrasted the same with original BFKL equation. Then we extract the collinear gluon density $xg(x,Q^2)$ from unintegrated gluon distributions $f(x,k_t^2)$ and compared our theoretical prediction with that of global data fits viz. NNPDF3.1sx and CT14. Finally we assess the sensitivity of $f(x,k_t^2)$ towards BFKL intercept $\lambda$ for three canonical choices of $\lambda$ viz. o.4, 0.5 and 0.6.
[ { "created": "Sat, 15 Jun 2019 04:43:08 GMT", "version": "v1" } ]
2020-04-22
[ [ "Phukan", "P.", "" ], [ "Lalune", "M.", "" ], [ "Sarma", "J. K.", "" ] ]
We investigate the impact of so called kinematic constraint on gluon evolution at small $x$. Implanting the constraint on the real emission term of gluon ladder diagram, we obtain an integro-differential form of BFKL equation. Later we solve the equation analytically using the method of characteristics. We sketch the Bjorken x and transverse momentum $k_t^2$ dependence of our solution of unintegrated gluon distributions $f(x,k_t^2)$ in kinematic constraint supplemented BFKL equation and contrasted the same with original BFKL equation. Then we extract the collinear gluon density $xg(x,Q^2)$ from unintegrated gluon distributions $f(x,k_t^2)$ and compared our theoretical prediction with that of global data fits viz. NNPDF3.1sx and CT14. Finally we assess the sensitivity of $f(x,k_t^2)$ towards BFKL intercept $\lambda$ for three canonical choices of $\lambda$ viz. o.4, 0.5 and 0.6.
hep-ph/0311062
Hubert Spiesberger
G. Kramer and H. Spiesberger
Inclusive Photoproduction of D* Mesons with Massive Charm Quarks
18 pages, 9 figures, figures modified to include statistical and systematic experimental errors
Eur.Phys.J. C38 (2004) 309-318
10.1140/epjc/s2004-02054-5
DESY 04-196, MZ-TH/03-18
hep-ph
null
We have calculated the next-to-leading order cross sections for the inclusive production of D* mesons in gamma-p collisions at HERA in two approaches using massive or massless charm quarks. The usual massive theory for the direct cross section with charm quarks only in the final state was transformed into a massive theory with MS-bar subtraction by subtracting the mass divergent and additional finite terms calculated earlier in connection with the process gamma+gamma -> D*+X. This theory approaches the massless theory with increasing transverse momentum. The difference between the massive and the massless approach with MS-bar subtraction is studied in detail in those kinematic regions relevant for comparison with experimental data. With these results and including the resolved cross section which is dominated by the part originating from the charm in the photon, we compute the fully inclusive D* cross section and compare it with preliminary data from the ZEUS collaboration at HERA. We find on average good agreement.
[ { "created": "Wed, 5 Nov 2003 15:21:20 GMT", "version": "v1" }, { "created": "Mon, 4 Oct 2004 12:23:43 GMT", "version": "v2" } ]
2009-11-10
[ [ "Kramer", "G.", "" ], [ "Spiesberger", "H.", "" ] ]
We have calculated the next-to-leading order cross sections for the inclusive production of D* mesons in gamma-p collisions at HERA in two approaches using massive or massless charm quarks. The usual massive theory for the direct cross section with charm quarks only in the final state was transformed into a massive theory with MS-bar subtraction by subtracting the mass divergent and additional finite terms calculated earlier in connection with the process gamma+gamma -> D*+X. This theory approaches the massless theory with increasing transverse momentum. The difference between the massive and the massless approach with MS-bar subtraction is studied in detail in those kinematic regions relevant for comparison with experimental data. With these results and including the resolved cross section which is dominated by the part originating from the charm in the photon, we compute the fully inclusive D* cross section and compare it with preliminary data from the ZEUS collaboration at HERA. We find on average good agreement.
1910.08316
Igor Ivanov
Igor P. Ivanov, Celso C. Nishi
Discriminating between $CP$ and family transformations in the bilinear space of NHDM
7 pages
Phys. Rev. D 101, 015023 (2020)
10.1103/PhysRevD.101.015023
CFTP/19-028
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The scalar potential of the N-Higgs-doublet model (NHDM) is best analyzed not in the space of N complex doublets $\phi_a$ but in the $N^2$-dimensional space of real-valued bilinears constructed of $\phi_a^\dagger \phi_b$. In particular, many insights have been gained into CP violation in the 2HDM and 3HDM by studying how generalized CP transformations (GCPs) act in this bilinear space. These insights relied on the fact that GCPs, which involved an odd number of mirror reflection, could be clearly distinguished from Higgs family transformations by the sign of the determinant of the transformation matrix. It was recently pointed out that this criterion fails starting from 4HDM, where the reflection/rotation dichotomy does not exist anymore. In this paper, we restore intuition by finding a different quantity which faithfully discriminates between GCPs and Higgs family transformations in the bilinear space for any number of Higgs doublets. We also establish the necessary and sufficient conditions for an orthogonal transformation in the bilinear space to represent a viable transformation back in the space of N doublets, which is helpful if one prefers to build an NHDM directly in the bilinear space.
[ { "created": "Fri, 18 Oct 2019 09:20:53 GMT", "version": "v1" } ]
2020-02-05
[ [ "Ivanov", "Igor P.", "" ], [ "Nishi", "Celso C.", "" ] ]
The scalar potential of the N-Higgs-doublet model (NHDM) is best analyzed not in the space of N complex doublets $\phi_a$ but in the $N^2$-dimensional space of real-valued bilinears constructed of $\phi_a^\dagger \phi_b$. In particular, many insights have been gained into CP violation in the 2HDM and 3HDM by studying how generalized CP transformations (GCPs) act in this bilinear space. These insights relied on the fact that GCPs, which involved an odd number of mirror reflection, could be clearly distinguished from Higgs family transformations by the sign of the determinant of the transformation matrix. It was recently pointed out that this criterion fails starting from 4HDM, where the reflection/rotation dichotomy does not exist anymore. In this paper, we restore intuition by finding a different quantity which faithfully discriminates between GCPs and Higgs family transformations in the bilinear space for any number of Higgs doublets. We also establish the necessary and sufficient conditions for an orthogonal transformation in the bilinear space to represent a viable transformation back in the space of N doublets, which is helpful if one prefers to build an NHDM directly in the bilinear space.
hep-ph/0008115
Pedro Miguel Martins Ferreira
P.M. Ferreira
A full one-loop charge symmetry breaking effective potential
11 pages, 2 figures
Phys.Lett. B509 (2001) 120-130; Erratum-ibid. B518 (2001) 333
10.1016/S0370-2693(01)00552-4
null
hep-ph
null
We calculate the one-loop contributions to the effective potential for the minimal supersymmetric model when scalar fields other than the Higgses have vacuum expectation values. The importance of these contributions for studies of charge and colour breaking bounds is discussed.
[ { "created": "Fri, 11 Aug 2000 17:03:54 GMT", "version": "v1" }, { "created": "Fri, 8 Dec 2000 18:25:56 GMT", "version": "v2" }, { "created": "Mon, 11 Dec 2000 14:58:52 GMT", "version": "v3" }, { "created": "Tue, 9 Jan 2001 19:05:06 GMT", "version": "v4" }, { "created": "Tue, 12 Jun 2001 15:17:00 GMT", "version": "v5" } ]
2009-10-31
[ [ "Ferreira", "P. M.", "" ] ]
We calculate the one-loop contributions to the effective potential for the minimal supersymmetric model when scalar fields other than the Higgses have vacuum expectation values. The importance of these contributions for studies of charge and colour breaking bounds is discussed.
1302.4227
Tomasz Stebel
Michal Praszalowicz and Tomasz Stebel
Quantitative Study of Different Forms of Geometrical Scaling in Deep Inelastic Scattering at HERA
13 pages, 6 figures
JHEP 04 (2013) 169
10.1007/JHEP04(2013)169
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use recently proposed method of ratios to assess the quality of geometrical scaling in deep inelastic scattering for different forms of the saturation scale. We consider original form of geometrical scaling (motivated by the Balitski-Kovchegov (BK) equation with fixed coupling) studied in more detail in our previous paper, and four new hypotheses: phenomenologically motivated case with $Q^2$ dependent exponent $\lambda$ that governs small $x$ dependence of the saturation scale, two versions of scaling (running coupling 1 and 2) that follow from the BK equation with running coupling, and diffusive scaling suggested by the QCD evolution equation beyond mean field approximation. It turns out that more sophisticated scenarios: running coupling scaling and diffusive scaling are disfavored by the combined HERA data on $e^+p$ deep inelastic structure function $F_2$.
[ { "created": "Mon, 18 Feb 2013 11:16:18 GMT", "version": "v1" } ]
2015-06-04
[ [ "Praszalowicz", "Michal", "" ], [ "Stebel", "Tomasz", "" ] ]
We use recently proposed method of ratios to assess the quality of geometrical scaling in deep inelastic scattering for different forms of the saturation scale. We consider original form of geometrical scaling (motivated by the Balitski-Kovchegov (BK) equation with fixed coupling) studied in more detail in our previous paper, and four new hypotheses: phenomenologically motivated case with $Q^2$ dependent exponent $\lambda$ that governs small $x$ dependence of the saturation scale, two versions of scaling (running coupling 1 and 2) that follow from the BK equation with running coupling, and diffusive scaling suggested by the QCD evolution equation beyond mean field approximation. It turns out that more sophisticated scenarios: running coupling scaling and diffusive scaling are disfavored by the combined HERA data on $e^+p$ deep inelastic structure function $F_2$.
1802.06874
Binoy Patra Krishna
Mujeeb Hasan, Binoy Krishna Patra, Bhaswar Chatterjee, and Partha Bagchi
Landau Damping in a strong magnetic field: Dissociation of Quarkonia
28 pages with 11 figures
null
null
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have investigated the effects of strong magnetic field on the properties of quarkonia immersed in a thermal medium of quarks and gluons and studied its quasi-free dissociation due to the Landau-damping. Thermalizing the Schwinger propagator in the lowest Landau levels for quarks and the Feynman propagator for gluons in real-time formalism, we have calculated the resummed retarded and symmetric propagators, which in turn give the real and imaginary components of dielectric permittivity, respectively. The magnetic field affects the large-distance interaction more than the short-distance interaction, as a result, the real part of potential becomes more attractive and the magnitude of imaginary part too becomes larger, compared to the thermal medium in absence of strong magnetic field. As a consequence the average size of $J/\psi$'s and $\psi^\prime$'s are increased but $\chi_c$'s get shrunk. Similarly the magnetic field affects the binding of $J/\psi$'s and $\chi_c$'s discriminately, i.e. it decreases the binding of $J/\psi$ and increases for $\chi_c$. However, the further increase in magnetic field results in the decrease of binding energies. On contrary the magnetic field increases the width of the resonances, unless the temperature is sufficiently high. We have finally studied how the presence of magnetic field affects the dissolution of quarkonia in a thermal medium due to the Landau damping, where the dissociation temperatures are found to increase compared to the thermal medium in absence of magnetic field. However, further increase of magnetic field decreases the dissociation temperatures. For example, $J/\psi$'s and $\chi_c$'s are dissociated at higher temperatures at 2 $T_c$ and 1.1 $T_c$ at a magnetic field $eB \approx 6~{\rm{and}}~4~m_\pi^2$, respectively, compared to the values 1.60 $T_c$ and 0.8 $T_c$ in the absence of magnetic field, respectively.
[ { "created": "Fri, 16 Feb 2018 13:23:22 GMT", "version": "v1" } ]
2018-02-21
[ [ "Hasan", "Mujeeb", "" ], [ "Patra", "Binoy Krishna", "" ], [ "Chatterjee", "Bhaswar", "" ], [ "Bagchi", "Partha", "" ] ]
We have investigated the effects of strong magnetic field on the properties of quarkonia immersed in a thermal medium of quarks and gluons and studied its quasi-free dissociation due to the Landau-damping. Thermalizing the Schwinger propagator in the lowest Landau levels for quarks and the Feynman propagator for gluons in real-time formalism, we have calculated the resummed retarded and symmetric propagators, which in turn give the real and imaginary components of dielectric permittivity, respectively. The magnetic field affects the large-distance interaction more than the short-distance interaction, as a result, the real part of potential becomes more attractive and the magnitude of imaginary part too becomes larger, compared to the thermal medium in absence of strong magnetic field. As a consequence the average size of $J/\psi$'s and $\psi^\prime$'s are increased but $\chi_c$'s get shrunk. Similarly the magnetic field affects the binding of $J/\psi$'s and $\chi_c$'s discriminately, i.e. it decreases the binding of $J/\psi$ and increases for $\chi_c$. However, the further increase in magnetic field results in the decrease of binding energies. On contrary the magnetic field increases the width of the resonances, unless the temperature is sufficiently high. We have finally studied how the presence of magnetic field affects the dissolution of quarkonia in a thermal medium due to the Landau damping, where the dissociation temperatures are found to increase compared to the thermal medium in absence of magnetic field. However, further increase of magnetic field decreases the dissociation temperatures. For example, $J/\psi$'s and $\chi_c$'s are dissociated at higher temperatures at 2 $T_c$ and 1.1 $T_c$ at a magnetic field $eB \approx 6~{\rm{and}}~4~m_\pi^2$, respectively, compared to the values 1.60 $T_c$ and 0.8 $T_c$ in the absence of magnetic field, respectively.
1212.2970
Joerg Jaeckel
Dieter Horns, Joerg Jaeckel, Axel Lindner, Andrei Lobanov, Javier Redondo and Andreas Ringwald
Searching for WISPy Cold Dark Matter with a Dish Antenna
16 pages, 3 figures
null
10.1088/1475-7516/2013/04/016
DESY 12-227; MPP-2012-158
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The cold dark matter of the Universe may be comprised of very light and very weakly interacting particles, so-called WISPs. Two prominent examples are hidden photons and axion-like particles. In this note we propose a new technique to sensitively search for this type of dark matter with dish antennas. The technique is broadband and allows to explore a whole range of masses in a single measurement.
[ { "created": "Wed, 12 Dec 2012 21:00:03 GMT", "version": "v1" } ]
2015-06-12
[ [ "Horns", "Dieter", "" ], [ "Jaeckel", "Joerg", "" ], [ "Lindner", "Axel", "" ], [ "Lobanov", "Andrei", "" ], [ "Redondo", "Javier", "" ], [ "Ringwald", "Andreas", "" ] ]
The cold dark matter of the Universe may be comprised of very light and very weakly interacting particles, so-called WISPs. Two prominent examples are hidden photons and axion-like particles. In this note we propose a new technique to sensitively search for this type of dark matter with dish antennas. The technique is broadband and allows to explore a whole range of masses in a single measurement.
2211.01616
Zhi-zhong Xing
Zhi-zhong Xing
Towards identifying the minimal flavor symmetry behind neutrino oscillations
6 pages, 2 figures. Contribution to ICHEP2022
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Current neutrino oscillation data indicate that the $3\times 3$ Pontecorvo-Maki-Nakagawa-Sakata matrix $U$ exhibits a $\mu$-$\tau$ flavor interchange symmetry $|U^{}_{\mu i}| = |U^{}_{\tau i}|$ (for $i = 1, 2, 3$) as a good approximation. In particular, the T2K measurement implies that the maximal neutrino mixing angle $\theta^{}_{23}$ and the CP-violating phase $\delta$ should be close to $\pi/4$ and $-\pi/2$, respectively. Behind these observations lies a minimal flavor symmetry -- - the effective Majorana neutrino mass term keeps invariant under the transformations $\nu^{}_{e \rm L} \to (\nu^{}_{e \rm L})^c$, $\nu^{}_{\mu \rm L} \to (\nu^{}_{\tau \rm L})^c$ and $\nu^{}_{\tau \rm L} \to (\nu^{}_{\mu \rm L})^c$. Extending this flavor symmetry to the canonical seesaw mechanism, we find that the $R$-matrix describing the strength of weak charged-current interactions of heavy Majorana neutrinos satisfies $|R^{}_{\mu i}| = |R^{}_{\tau i}|$ as a consequence of $|U^{}_{\mu i}| = |U^{}_{\tau i}|$. This result can be used to set a new upper bound, which is about three orders of magnitude more stringent than before, on the flavor mixing factor associated with the charged-lepton-flavor-violating decay mode $\tau^- \to e^- + \gamma$.
[ { "created": "Thu, 3 Nov 2022 07:10:15 GMT", "version": "v1" } ]
2022-11-04
[ [ "Xing", "Zhi-zhong", "" ] ]
Current neutrino oscillation data indicate that the $3\times 3$ Pontecorvo-Maki-Nakagawa-Sakata matrix $U$ exhibits a $\mu$-$\tau$ flavor interchange symmetry $|U^{}_{\mu i}| = |U^{}_{\tau i}|$ (for $i = 1, 2, 3$) as a good approximation. In particular, the T2K measurement implies that the maximal neutrino mixing angle $\theta^{}_{23}$ and the CP-violating phase $\delta$ should be close to $\pi/4$ and $-\pi/2$, respectively. Behind these observations lies a minimal flavor symmetry -- - the effective Majorana neutrino mass term keeps invariant under the transformations $\nu^{}_{e \rm L} \to (\nu^{}_{e \rm L})^c$, $\nu^{}_{\mu \rm L} \to (\nu^{}_{\tau \rm L})^c$ and $\nu^{}_{\tau \rm L} \to (\nu^{}_{\mu \rm L})^c$. Extending this flavor symmetry to the canonical seesaw mechanism, we find that the $R$-matrix describing the strength of weak charged-current interactions of heavy Majorana neutrinos satisfies $|R^{}_{\mu i}| = |R^{}_{\tau i}|$ as a consequence of $|U^{}_{\mu i}| = |U^{}_{\tau i}|$. This result can be used to set a new upper bound, which is about three orders of magnitude more stringent than before, on the flavor mixing factor associated with the charged-lepton-flavor-violating decay mode $\tau^- \to e^- + \gamma$.
hep-ph/0506251
Robert Thorne S
R.S. Thorne
A Variable Flavour Number Scheme at NNLO
4 pages, 6 figures included as .ps files. To appear in proceedings of DIS05, XIII International Workshop on Deep Inelastic Scattering
AIPConf.Proc.792:847-850,2005
10.1063/1.2122169
Cavendish-HEP-05/11
hep-ph
null
I present a formulation of a Variable Flavour Number Scheme for heavy quarks that is implemented up to NNLO in the strong coupling constant and may be used in NNLO global fits for parton distributions.
[ { "created": "Fri, 24 Jun 2005 14:01:49 GMT", "version": "v1" } ]
2009-11-11
[ [ "Thorne", "R. S.", "" ] ]
I present a formulation of a Variable Flavour Number Scheme for heavy quarks that is implemented up to NNLO in the strong coupling constant and may be used in NNLO global fits for parton distributions.
1112.5142
Stefan Kallweit
A. Denner (Wurzburg U.), S. Dittmaier (Freiburg U.), S. Kallweit (Zurich U. and PSI, Villigen), A. M\"uck (RWTH Aachen U.)
Electroweak corrections to Higgs-strahlung off W/Z bosons at the Tevatron and the LHC with HAWK
22 pp
null
10.1007/JHEP03(2012)075
FR-PHENO-2011-025; PSI-PR-11-04; ZU-TH-29-11; TTK-11-61
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The associate production of Higgs bosons with W or Z bosons, known as Higgs-strahlung, is an important search channel for Higgs bosons at the hadron colliders Tevatron and LHC for low Higgs-boson masses. We refine a previous calculation of next-to-leading-order electroweak corrections (and recalculate the QCD corrections) upon including the leptonic decay of the W/Z bosons, thereby keeping the fully differential information of the 2-lepton + Higgs final state. The gauge invariance of the W/Z-resonance treatment is ensured by the use of the complex-mass scheme. The electroweak corrections, which are at the level of -(5-10)% for total cross sections, further increase in size with increasing transverse momenta p_T in differential cross sections. For instance, for p_T,H >~ 200GeV, which is the interesting range at the LHC, the electroweak corrections to WH production reach about -14% for M_H = 120GeV. The described corrections are implemented in the HAWK Monte Carlo program, which was initially designed for the vector-boson-fusion channel, and are discussed for various distributions in the production channels pp / p \bar p -> H + l nu_l / l^-l^+ / nu_l \bar nu_l + X.
[ { "created": "Wed, 21 Dec 2011 19:44:55 GMT", "version": "v1" } ]
2015-06-03
[ [ "Denner", "A.", "", "Wurzburg U." ], [ "Dittmaier", "S.", "", "Freiburg U." ], [ "Kallweit", "S.", "", "Zurich U. and PSI, Villigen" ], [ "Mück", "A.", "", "RWTH Aachen U." ] ]
The associate production of Higgs bosons with W or Z bosons, known as Higgs-strahlung, is an important search channel for Higgs bosons at the hadron colliders Tevatron and LHC for low Higgs-boson masses. We refine a previous calculation of next-to-leading-order electroweak corrections (and recalculate the QCD corrections) upon including the leptonic decay of the W/Z bosons, thereby keeping the fully differential information of the 2-lepton + Higgs final state. The gauge invariance of the W/Z-resonance treatment is ensured by the use of the complex-mass scheme. The electroweak corrections, which are at the level of -(5-10)% for total cross sections, further increase in size with increasing transverse momenta p_T in differential cross sections. For instance, for p_T,H >~ 200GeV, which is the interesting range at the LHC, the electroweak corrections to WH production reach about -14% for M_H = 120GeV. The described corrections are implemented in the HAWK Monte Carlo program, which was initially designed for the vector-boson-fusion channel, and are discussed for various distributions in the production channels pp / p \bar p -> H + l nu_l / l^-l^+ / nu_l \bar nu_l + X.
1403.3216
Alexander Huss
Stefan Dittmaier, Alexander Huss, Christian Schwinn
Mixed QCD-electroweak O(\alpha_s\alpha) corrections to Drell-Yan processes in the resonance region: pole approximation and non-factorizable corrections
56 pages, 22 figures
null
10.1016/j.nuclphysb.2014.05.027
FR-PHENO-2013-014
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Drell-Yan-like W-boson and Z-boson production in the resonance region allows for high-precision measurements that are crucial to carry experimental tests of the Standard Model to the extremes, such as the determination of the W-boson mass and the effective weak mixing angle. In this article, we establish a framework for the calculation of the mixed QCD-electroweak O(\alpha_s\alpha) corrections to Drell-Yan processes in the resonance region, which are one of the main remaining theoretical uncertainties. We describe how the Standard Model prediction can be successfully performed in terms of a consistent expansion about the resonance poles, which classifies the corrections in terms of factorizable and non-factorizable contributions. The former can be attributed to the W/Z production and decay subprocesses individually, while the latter link production and decay by soft-photon exchange. At next-to-leading order we compare the full electroweak corrections with the pole-expanded approximations, confirming the validity of the approximation. At O(\alpha_s\alpha), we describe the concept of the expansion and explicitly give results on the non-factorizable contributions, which turn out to be phenomenologically negligible. Our results, thus, demonstrate that for phenomenological purposes the O(\alpha_s\alpha) corrections can be factorized into terms associated with initial-state and/or final-state corrections. Moreover, we argue that the factorization properties of the non-factorizable corrections at O(\alpha_s\alpha) from lower-order O(\alpha_s) graphs generalize to any order in O(\alpha_s^n\alpha).
[ { "created": "Thu, 13 Mar 2014 09:57:50 GMT", "version": "v1" } ]
2015-06-19
[ [ "Dittmaier", "Stefan", "" ], [ "Huss", "Alexander", "" ], [ "Schwinn", "Christian", "" ] ]
Drell-Yan-like W-boson and Z-boson production in the resonance region allows for high-precision measurements that are crucial to carry experimental tests of the Standard Model to the extremes, such as the determination of the W-boson mass and the effective weak mixing angle. In this article, we establish a framework for the calculation of the mixed QCD-electroweak O(\alpha_s\alpha) corrections to Drell-Yan processes in the resonance region, which are one of the main remaining theoretical uncertainties. We describe how the Standard Model prediction can be successfully performed in terms of a consistent expansion about the resonance poles, which classifies the corrections in terms of factorizable and non-factorizable contributions. The former can be attributed to the W/Z production and decay subprocesses individually, while the latter link production and decay by soft-photon exchange. At next-to-leading order we compare the full electroweak corrections with the pole-expanded approximations, confirming the validity of the approximation. At O(\alpha_s\alpha), we describe the concept of the expansion and explicitly give results on the non-factorizable contributions, which turn out to be phenomenologically negligible. Our results, thus, demonstrate that for phenomenological purposes the O(\alpha_s\alpha) corrections can be factorized into terms associated with initial-state and/or final-state corrections. Moreover, we argue that the factorization properties of the non-factorizable corrections at O(\alpha_s\alpha) from lower-order O(\alpha_s) graphs generalize to any order in O(\alpha_s^n\alpha).
0910.0785
Owe Philipsen
Owe Philipsen
Towards a determination of the chiral critical surface of QCD
8 pages, 6 figures; Invited talk given at CPOD 2009, June 8-12 2009, Brookhaven, NY
PoS CPOD2009:026,2009
null
MS-TP-09-20
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The chiral critical surface is a surface of second order phase transitions bounding the region of first order chiral phase transitions for small quark masses in the {m_{u,d}, m_s,\mu} parameter space. The potential critical endpoint of the QCD (T,\mu)-phase diagram is widely expected to be part of this surface. Since for \mu=0 with physical quark masses QCD is known to exhibit an analytic crossover, this expectation requires the region of chiral transitions to expand with \mu for a chiral critical endpoint to exist. Instead, on coarse N_t=4 lattices, we find the area of chiral transitions to shrink with \mu, which excludes a chiral critical point for QCD at moderate chemical potentials \mu_B < 500 MeV. First results on finer N_t=6 lattices indicate a curvature of the critical surface consistent with zero and unchanged conclusions. We also comment on the interplay of phase diagrams between the N_f=2 and N_f=2+1 theories and its consequences for physical QCD.
[ { "created": "Mon, 5 Oct 2009 15:07:06 GMT", "version": "v1" } ]
2014-11-20
[ [ "Philipsen", "Owe", "" ] ]
The chiral critical surface is a surface of second order phase transitions bounding the region of first order chiral phase transitions for small quark masses in the {m_{u,d}, m_s,\mu} parameter space. The potential critical endpoint of the QCD (T,\mu)-phase diagram is widely expected to be part of this surface. Since for \mu=0 with physical quark masses QCD is known to exhibit an analytic crossover, this expectation requires the region of chiral transitions to expand with \mu for a chiral critical endpoint to exist. Instead, on coarse N_t=4 lattices, we find the area of chiral transitions to shrink with \mu, which excludes a chiral critical point for QCD at moderate chemical potentials \mu_B < 500 MeV. First results on finer N_t=6 lattices indicate a curvature of the critical surface consistent with zero and unchanged conclusions. We also comment on the interplay of phase diagrams between the N_f=2 and N_f=2+1 theories and its consequences for physical QCD.
hep-ph/0408326
Kentarou Mawatari
T. Matsuki, K. Mawatari, T. Morii, K. Sudoh
Spinor Operator Giving Both Angular Momentum and Parity
4 pages, revtex
null
null
TKU-TH-0401, KOBE-FHD-04-03
hep-ph
null
In heavy quark effective theory, heavy mesons which contain a heavy quark (or antiquark) are classified by $s_l^{pi_l}$, i.e., the total angular momentum $s_l$ and the parity $pi_l$ of the light quark degrees of freedom around a static heavy quark. In this case, however, one needs to separately estimate the parity other than the angular momentum of a light quark to describe heavy mesons. A new operator $K$ was proposed some time ago by two of us (T.M. and T.M.). In this Letter, we show that the quantum number $k$ of this operator is enough to describe both the total angular momentum of the light quark degrees of freedom and the parity of a heavy meson, and derive a simple relation between $k$ and $s_l^{pi_l}$.
[ { "created": "Sun, 29 Aug 2004 23:42:56 GMT", "version": "v1" } ]
2007-05-23
[ [ "Matsuki", "T.", "" ], [ "Mawatari", "K.", "" ], [ "Morii", "T.", "" ], [ "Sudoh", "K.", "" ] ]
In heavy quark effective theory, heavy mesons which contain a heavy quark (or antiquark) are classified by $s_l^{pi_l}$, i.e., the total angular momentum $s_l$ and the parity $pi_l$ of the light quark degrees of freedom around a static heavy quark. In this case, however, one needs to separately estimate the parity other than the angular momentum of a light quark to describe heavy mesons. A new operator $K$ was proposed some time ago by two of us (T.M. and T.M.). In this Letter, we show that the quantum number $k$ of this operator is enough to describe both the total angular momentum of the light quark degrees of freedom and the parity of a heavy meson, and derive a simple relation between $k$ and $s_l^{pi_l}$.
0909.0753
Keith Rehermann
David E. Kaplan, Gordan Z. Krnjaic, Keith R. Rehermann, Christopher M. Wells
Atomic Dark Matter
17 pages, 3 figures
null
10.1088/1475-7516/2010/05/021
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has interesting implications for cosmology as well as direct detection: Protohalo formation can be suppressed below $M_{proto} \sim 10^3 - 10^6 M_{\odot}$ for weak scale dark matter due to Ion-Radiation interactions in the dark sector. Moreover, weak-scale dark atoms can accommodate hyperfine splittings of order $100 \kev$, consistent with the inelastic dark matter interpretation of the DAMA data while naturally evading direct detection bounds.
[ { "created": "Thu, 3 Sep 2009 21:29:30 GMT", "version": "v1" } ]
2015-05-14
[ [ "Kaplan", "David E.", "" ], [ "Krnjaic", "Gordan Z.", "" ], [ "Rehermann", "Keith R.", "" ], [ "Wells", "Christopher M.", "" ] ]
We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has interesting implications for cosmology as well as direct detection: Protohalo formation can be suppressed below $M_{proto} \sim 10^3 - 10^6 M_{\odot}$ for weak scale dark matter due to Ion-Radiation interactions in the dark sector. Moreover, weak-scale dark atoms can accommodate hyperfine splittings of order $100 \kev$, consistent with the inelastic dark matter interpretation of the DAMA data while naturally evading direct detection bounds.
2009.00559
Smita Chakraborty
Smita Chakraborty
String shoving effects on jets in p-p collisions
5 pages, 4 figures, Prepared for publication in the proceedings for 10th International Conference on Hard and Electromagnetic Probes in High-Energy Nuclear Collisions, 1-5th June 2020, Austin, Texas
null
10.22323/1.387.0134
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Di-jet observables are excellent probes to study the effect of jets in dense systems. Interacting Lund strings will affect jet observables and suggests a new common mechanism responsible for jet modification in p-A and A-A. In this proceeding, we present our new implementation of the string shoving mechanism in PYTHIA8 which lets us study the effects on jet observables in p-p and nuclear collisions. We also present preliminary results showing the effects in hadron-jet correlation studies.
[ { "created": "Tue, 1 Sep 2020 16:43:31 GMT", "version": "v1" } ]
2022-09-21
[ [ "Chakraborty", "Smita", "" ] ]
Di-jet observables are excellent probes to study the effect of jets in dense systems. Interacting Lund strings will affect jet observables and suggests a new common mechanism responsible for jet modification in p-A and A-A. In this proceeding, we present our new implementation of the string shoving mechanism in PYTHIA8 which lets us study the effects on jet observables in p-p and nuclear collisions. We also present preliminary results showing the effects in hadron-jet correlation studies.
hep-ph/0410384
Ailin Zhang
Ailin Zhang and T. G. Steele
Analysis of Exotic Hybrid eta pion, eta-prime pion Decays
4 pages, talk presented at the 10th International Symposium on Meson-Nucleon Physics and the Structure of the Nucleon(MENU2004), Beijing, China, August 29 to September 4, 2004
Int.J.Mod.Phys. A20 (2005) 1973-1976
10.1142/S0217751X05023761
null
hep-ph
null
Investigations of the mass and decays of the exotic hybrid are reviewed, including calculation of the pion1 to eta pion, eta-prime pion decay widths within the QCD sum rules technique. In this calculation, the recently-proposed eta, eta-prime quark mixing scheme is employed. The results indicate that the decay width Gamma(pion1 to eta pion) around 250 MeV is large compared with the decay width Gamma(pion1 to eta-prime pion) around 20 MeV. Inspired by these results, some phenomenological approaches are suggested to gain an understanding of the underlying mechanism of eta pion and eta-prime pion hybrid decays.
[ { "created": "Thu, 28 Oct 2004 12:35:57 GMT", "version": "v1" } ]
2009-11-10
[ [ "Zhang", "Ailin", "" ], [ "Steele", "T. G.", "" ] ]
Investigations of the mass and decays of the exotic hybrid are reviewed, including calculation of the pion1 to eta pion, eta-prime pion decay widths within the QCD sum rules technique. In this calculation, the recently-proposed eta, eta-prime quark mixing scheme is employed. The results indicate that the decay width Gamma(pion1 to eta pion) around 250 MeV is large compared with the decay width Gamma(pion1 to eta-prime pion) around 20 MeV. Inspired by these results, some phenomenological approaches are suggested to gain an understanding of the underlying mechanism of eta pion and eta-prime pion hybrid decays.
hep-ph/9503284
null
Chih-Hao Chen
MULTI-CHANNEL SEARCH FOR SUPERGRAVITY AT THE LARGE HADRON COLLIDER
proceedings for 'BEYOND THE STANDARD MODEL IV' conference; 3 pages; an unencoded postscript figure was appended
null
null
FSU-HEP-950309
hep-ph
null
The potential of seeing supersymmetry (SUSY) at the CERN Large Hadron Collider (LHC) was studied by looking at 3 types of signals: dilepton events from slepton pair productions, trilepton events from chargino/neutralino productions and missing energy plus multi-jet events from gluino/squark productions. I described my results by mapping out reachable areas in the supergravity parameter space. Areas explorable at LEP II were also mapped out for comparison.
[ { "created": "Thu, 9 Mar 1995 23:04:31 GMT", "version": "v1" } ]
2016-09-01
[ [ "Chen", "Chih-Hao", "" ] ]
The potential of seeing supersymmetry (SUSY) at the CERN Large Hadron Collider (LHC) was studied by looking at 3 types of signals: dilepton events from slepton pair productions, trilepton events from chargino/neutralino productions and missing energy plus multi-jet events from gluino/squark productions. I described my results by mapping out reachable areas in the supergravity parameter space. Areas explorable at LEP II were also mapped out for comparison.
hep-ph/0504139
Igor Ivanov
F. Caporale, I. P. Ivanov
Production of spin-3 mesons in diffractive DIS
18 pages, 5 figures; v2: correction in Eq.(13), numerical results slightly shifted; conclusions unchanged
Eur.Phys.J.C44:505-514,2005
10.1140/epjc/s2005-02379-5
null
hep-ph
null
We calculate the amplitudes of J^{PC}=3^{--} meson production in diffractive DIS within the k_t-factorization approach, with a particular attention paid to the rho_3(1690) meson. We find that at all Q^2 the rho_3(1690) production cross section is 2-5 times smaller than the rho(1700) production cross section, which is assumed to be a pure D-wave state. Studying sigma_L and sigma_T separately, we observe domination of rho_3 in sigma_L and domination of rho(1700) in sigma_T and offer an explanation of this behavior in simple terms. We also find very strong contributions -- sometimes even domination -- of the s-channel helicity violating amplitudes. The typical color dipole sizes probed in rho_3 production are shown to be larger than those in the ground state rho production, and the energy dependence of rho_3 cross section turns out to be much flatter than the rho production cross section. All the conclusions about the relative behavior of rho_3(1690) and rho(1700) mesons are numerically stable against variations of input parameters.
[ { "created": "Sat, 16 Apr 2005 14:09:08 GMT", "version": "v1" }, { "created": "Wed, 1 Jun 2005 07:39:00 GMT", "version": "v2" } ]
2009-01-07
[ [ "Caporale", "F.", "" ], [ "Ivanov", "I. P.", "" ] ]
We calculate the amplitudes of J^{PC}=3^{--} meson production in diffractive DIS within the k_t-factorization approach, with a particular attention paid to the rho_3(1690) meson. We find that at all Q^2 the rho_3(1690) production cross section is 2-5 times smaller than the rho(1700) production cross section, which is assumed to be a pure D-wave state. Studying sigma_L and sigma_T separately, we observe domination of rho_3 in sigma_L and domination of rho(1700) in sigma_T and offer an explanation of this behavior in simple terms. We also find very strong contributions -- sometimes even domination -- of the s-channel helicity violating amplitudes. The typical color dipole sizes probed in rho_3 production are shown to be larger than those in the ground state rho production, and the energy dependence of rho_3 cross section turns out to be much flatter than the rho production cross section. All the conclusions about the relative behavior of rho_3(1690) and rho(1700) mesons are numerically stable against variations of input parameters.
1103.1647
Matthew McCullough
Rhys Davies, John March-Russell and Matthew McCullough
A Supersymmetric One Higgs Doublet Model
23 pages
JHEP 1104:108,2011
10.1007/JHEP04(2011)108
OUTP-11-36P
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a supersymmetric extension of the Standard Model in which only one electroweak doublet acquires a vacuum expectation value and gives mass to Standard Model fermions. As well as the novel accommodation of a Standard Model Higgs within a supersymmetric framework, this leads to a very predictive model, with some advantages over the MSSM. In particular, problems with proton decay, flavour changing neutral currents and large CP violation are ameliorated, primarily due to the presence of an anomaly-free R-symmetry. Since supersymmetry must be broken at a low scale, gravity-mediated effects which break the R-symmetry are naturally small. The R-symmetry requires the presence of adjoint chiral superfields, to give Dirac masses to the gauginos; these adjoints are the only non-MSSM fields in the visible sector. The LSP is a very light neutralino, which is mostly bino. Such a light neutralino is not in conflict with experiment, and is a striking prediction of the minimal model. Additional scenarios to raise the mass of this neutralino to the weak scale are also outlined. Prospects for discovery at the LHC are briefly discussed, along with viable scenarios for achieving gauge-coupling unification.
[ { "created": "Tue, 8 Mar 2011 21:21:34 GMT", "version": "v1" }, { "created": "Mon, 11 Apr 2011 09:53:14 GMT", "version": "v2" } ]
2011-04-28
[ [ "Davies", "Rhys", "" ], [ "March-Russell", "John", "" ], [ "McCullough", "Matthew", "" ] ]
We present a supersymmetric extension of the Standard Model in which only one electroweak doublet acquires a vacuum expectation value and gives mass to Standard Model fermions. As well as the novel accommodation of a Standard Model Higgs within a supersymmetric framework, this leads to a very predictive model, with some advantages over the MSSM. In particular, problems with proton decay, flavour changing neutral currents and large CP violation are ameliorated, primarily due to the presence of an anomaly-free R-symmetry. Since supersymmetry must be broken at a low scale, gravity-mediated effects which break the R-symmetry are naturally small. The R-symmetry requires the presence of adjoint chiral superfields, to give Dirac masses to the gauginos; these adjoints are the only non-MSSM fields in the visible sector. The LSP is a very light neutralino, which is mostly bino. Such a light neutralino is not in conflict with experiment, and is a striking prediction of the minimal model. Additional scenarios to raise the mass of this neutralino to the weak scale are also outlined. Prospects for discovery at the LHC are briefly discussed, along with viable scenarios for achieving gauge-coupling unification.
2101.08944
Jessica Howard
Jessica N. Howard, Stephan Mandt, Daniel Whiteson, Yibo Yang
Learning to Simulate High Energy Particle Collisions from Unlabeled Data
Accepted by Scientific Reports; Changes: Updated title and abstract, rearranged order of sections, added section 4.2, Figure 2, supplementary ablation study, and supplementary figures 2-4; 32 pages, 12 figures, 4 tables
Sci Rep 12, 7567 (2022)
10.1038/s41598-022-10966-7
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In many scientific fields which rely on statistical inference, simulations are often used to map from theoretical models to experimental data, allowing scientists to test model predictions against experimental results. Experimental data is often reconstructed from indirect measurements causing the aggregate transformation from theoretical models to experimental data to be poorly-described analytically. Instead, numerical simulations are used at great computational cost. We introduce Optimal-Transport-based Unfolding and Simulation (OTUS), a fast simulator based on unsupervised machine-learning that is capable of predicting experimental data from theoretical models. Without the aid of current simulation information, OTUS trains a probabilistic autoencoder to transform directly between theoretical models and experimental data. Identifying the probabilistic autoencoder's latent space with the space of theoretical models causes the decoder network to become a fast, predictive simulator with the potential to replace current, computationally-costly simulators. Here, we provide proof-of-principle results on two particle physics examples, $Z$-boson and top-quark decays, but stress that OTUS can be widely applied to other fields.
[ { "created": "Fri, 22 Jan 2021 04:16:16 GMT", "version": "v1" }, { "created": "Tue, 5 Jul 2022 22:53:08 GMT", "version": "v2" } ]
2022-07-07
[ [ "Howard", "Jessica N.", "" ], [ "Mandt", "Stephan", "" ], [ "Whiteson", "Daniel", "" ], [ "Yang", "Yibo", "" ] ]
In many scientific fields which rely on statistical inference, simulations are often used to map from theoretical models to experimental data, allowing scientists to test model predictions against experimental results. Experimental data is often reconstructed from indirect measurements causing the aggregate transformation from theoretical models to experimental data to be poorly-described analytically. Instead, numerical simulations are used at great computational cost. We introduce Optimal-Transport-based Unfolding and Simulation (OTUS), a fast simulator based on unsupervised machine-learning that is capable of predicting experimental data from theoretical models. Without the aid of current simulation information, OTUS trains a probabilistic autoencoder to transform directly between theoretical models and experimental data. Identifying the probabilistic autoencoder's latent space with the space of theoretical models causes the decoder network to become a fast, predictive simulator with the potential to replace current, computationally-costly simulators. Here, we provide proof-of-principle results on two particle physics examples, $Z$-boson and top-quark decays, but stress that OTUS can be widely applied to other fields.
2405.00880
Fabio L. Braghin
Fabio L. Braghin
$U_A(1)$ symmetry breaking quark interactions from vacuum polarization
14 pages, one figure, revised manuscript. The original version v1 was split into two manuscripts, this is the first one. Accepted for publication
null
null
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
By considering the one loop background field method for a quark-antiquark interaction, mediated by one (non perturbative) gluon exchange, sixth order quark effective interactions are derived and investigated in the limit of zero momentum transfer for large quark and/or gluon effective masses. They extend fourth order quark interactions worked out in previous works of the author. These interactions break $U_A(1)$ symmetry and may be either momentum independent or dependent. Part of these interactions vanish in the limit of massless quarks, and several other -- involving vector and/or axial quark currents -- survive. In the local limit of the resulting interactions, some phenomenological implications are presented, which correspond to corrections to the Nambu-Jona-Lasinio model. By means of the auxiliary field method, the local interactions give rise to three meson interactions whose values are compared to phenomenological values found in the literature. Contributions for meson-mixing parameters are calculated and compared to available results.
[ { "created": "Wed, 1 May 2024 21:44:53 GMT", "version": "v1" }, { "created": "Wed, 8 May 2024 22:49:47 GMT", "version": "v2" }, { "created": "Mon, 15 Jul 2024 20:57:46 GMT", "version": "v3" }, { "created": "Sat, 10 Aug 2024 14:58:29 GMT", "version": "v4" } ]
2024-08-13
[ [ "Braghin", "Fabio L.", "" ] ]
By considering the one loop background field method for a quark-antiquark interaction, mediated by one (non perturbative) gluon exchange, sixth order quark effective interactions are derived and investigated in the limit of zero momentum transfer for large quark and/or gluon effective masses. They extend fourth order quark interactions worked out in previous works of the author. These interactions break $U_A(1)$ symmetry and may be either momentum independent or dependent. Part of these interactions vanish in the limit of massless quarks, and several other -- involving vector and/or axial quark currents -- survive. In the local limit of the resulting interactions, some phenomenological implications are presented, which correspond to corrections to the Nambu-Jona-Lasinio model. By means of the auxiliary field method, the local interactions give rise to three meson interactions whose values are compared to phenomenological values found in the literature. Contributions for meson-mixing parameters are calculated and compared to available results.
2004.09918
Chao Shi
Chao Shi, Xiao-Tao He, Wen-Bao Jia, Qing-Wu Wang, Shu-Sheng Xu and Hong-Shi Zong
Chiral transition and the chiral charge density of the hot and dense QCD matter
null
null
10.1007/JHEP06(2020)122
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the chirally imbalanced hot and dense strongly interacting matter by means of the Dyson-Schwinger equations (DSEs). The chiral phase diagram is studied in the presence of chiral chemical potential $\mu_5$. The chiral quark condensate $\langle \bar{\psi} \psi \rangle$ is obtained with the Cornwall-Jackiw-Tomboulis (CJT) effective action in concert with the Rainbow truncation. Catalysis effect of dynamical chiral symmetry breaking (DCSB) by $\mu_5$ is observed. We examine with two popular gluon models and consistency is found within the DSE approach, as well as in comparison with lattice QCD. The CEP location $(\mu_E,T_E)$ shifts toward larger $T_E$ but constant $\mu_E$ as $\mu_5$ increases. A technique is then introduced to compute the chiral charge density $n_5$ from the fully dressed quark propagator. We find the $n_5$ generally increases with temperature $T$, quark number chemical potential $\mu$ and $\mu_5$. Since the chiral magnetic effect (CME) is typically investigated with peripheral collisions, we also investigate the finite size effect on $n_5$ and find an increase in $n_5$ with smaller system size.
[ { "created": "Tue, 21 Apr 2020 11:36:42 GMT", "version": "v1" } ]
2020-07-15
[ [ "Shi", "Chao", "" ], [ "He", "Xiao-Tao", "" ], [ "Jia", "Wen-Bao", "" ], [ "Wang", "Qing-Wu", "" ], [ "Xu", "Shu-Sheng", "" ], [ "Zong", "Hong-Shi", "" ] ]
We study the chirally imbalanced hot and dense strongly interacting matter by means of the Dyson-Schwinger equations (DSEs). The chiral phase diagram is studied in the presence of chiral chemical potential $\mu_5$. The chiral quark condensate $\langle \bar{\psi} \psi \rangle$ is obtained with the Cornwall-Jackiw-Tomboulis (CJT) effective action in concert with the Rainbow truncation. Catalysis effect of dynamical chiral symmetry breaking (DCSB) by $\mu_5$ is observed. We examine with two popular gluon models and consistency is found within the DSE approach, as well as in comparison with lattice QCD. The CEP location $(\mu_E,T_E)$ shifts toward larger $T_E$ but constant $\mu_E$ as $\mu_5$ increases. A technique is then introduced to compute the chiral charge density $n_5$ from the fully dressed quark propagator. We find the $n_5$ generally increases with temperature $T$, quark number chemical potential $\mu$ and $\mu_5$. Since the chiral magnetic effect (CME) is typically investigated with peripheral collisions, we also investigate the finite size effect on $n_5$ and find an increase in $n_5$ with smaller system size.
hep-ph/9708268
Ito Hitoshi
Hitoshi Ito
Two-Body Dirac Equation and Its Wave Function at the Origin
LaTeX, 12 pages
null
10.1063/1.56040
KNK 972
hep-ph
null
A relativistic equation is deduced for the bound state of two particles, by assuming a proper boundary condition for the propagation of the negative-energy states. It reduces to the (one-body)Dirac equation in the infinite limit of one of the constituent mass. It also has the symmetries to assure the existence of the anti-bound-state with the same mass. The interaction kernel(pseudo-potential) is systematically constructed by diagonalizing the Hamiltonian of the background field theory, by which the retardation effects are included in the interaction. Its wave function at the origin(WFO) behaves properly in a manner suggested by the covariant field theory. The equation can well be applied in the heavy quark effective theory. It can also be used as a starting equation for the unperturbed system in the rigorous perturbation theory of QED.
[ { "created": "Thu, 7 Aug 1997 06:48:26 GMT", "version": "v1" } ]
2016-09-06
[ [ "Ito", "Hitoshi", "" ] ]
A relativistic equation is deduced for the bound state of two particles, by assuming a proper boundary condition for the propagation of the negative-energy states. It reduces to the (one-body)Dirac equation in the infinite limit of one of the constituent mass. It also has the symmetries to assure the existence of the anti-bound-state with the same mass. The interaction kernel(pseudo-potential) is systematically constructed by diagonalizing the Hamiltonian of the background field theory, by which the retardation effects are included in the interaction. Its wave function at the origin(WFO) behaves properly in a manner suggested by the covariant field theory. The equation can well be applied in the heavy quark effective theory. It can also be used as a starting equation for the unperturbed system in the rigorous perturbation theory of QED.
hep-ph/0602040
Tianjun Li
Ilia Gogoladze, Tianjun Li, Qaisar Shafi
Higgs Boson Mass From Orbifold GUTs
20 pages, 4 figures, 4 tables, Complete two-loop RGEs included, references added, version to appear in PRD
Phys.Rev.D73:066008,2006
10.1103/PhysRevD.73.066008
BA-06-01
hep-ph
null
We consider a class of seven-dimensional N=1 supersymmetric orbifold GUTs in which the Standard Model (SM) gauge couplings and one of the Yukawa couplings (top quark, bottom quark or tau lepton) are unified, without low energy supersymmetry, at M_{GUT} \simeq 4 \times 10^{16} GeV. With gauge-top quark Yukawa coupling unification the SM Higgs boson mass is estimated to be 135 \pm 6 GeV, which increases to 144 \pm 4 GeV for gauge-bottom quark (or gauge-tau lepton) Yukawa coupling unification.
[ { "created": "Fri, 3 Feb 2006 17:48:57 GMT", "version": "v1" }, { "created": "Fri, 3 Mar 2006 18:19:54 GMT", "version": "v2" } ]
2011-05-12
[ [ "Gogoladze", "Ilia", "" ], [ "Li", "Tianjun", "" ], [ "Shafi", "Qaisar", "" ] ]
We consider a class of seven-dimensional N=1 supersymmetric orbifold GUTs in which the Standard Model (SM) gauge couplings and one of the Yukawa couplings (top quark, bottom quark or tau lepton) are unified, without low energy supersymmetry, at M_{GUT} \simeq 4 \times 10^{16} GeV. With gauge-top quark Yukawa coupling unification the SM Higgs boson mass is estimated to be 135 \pm 6 GeV, which increases to 144 \pm 4 GeV for gauge-bottom quark (or gauge-tau lepton) Yukawa coupling unification.
1601.05430
Jun Gao
Edmond L. Berger, Jun Gao, Chong Sheng Li, Ze Long Liu and Hua Xing Zhu
Charm-quark production in deep-inelastic neutrino scattering at NNLO in QCD
6 pages, 4 figures, version published in PRL
Phys. Rev. Lett. 116, 212002 (2016)
10.1103/PhysRevLett.116.212002
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a fully differential next-to-next-to-leading order calculation of charm quark production in charged-current deep-inelastic scattering, with full charm-quark mass dependence. The next-to-next-to-leading order corrections in perturbative quantum chromodynamics are found to be comparable in size to the next-to-leading order corrections in certain kinematic regions. We compare our predictions with data on dimuon production in (anti-)neutrino scattering from a heavy nucleus. Our results can be used to improve the extraction of the parton distribution function of a strange quark in the nucleon.
[ { "created": "Wed, 20 Jan 2016 21:01:02 GMT", "version": "v1" }, { "created": "Wed, 29 Jun 2016 02:58:28 GMT", "version": "v2" } ]
2016-06-30
[ [ "Berger", "Edmond L.", "" ], [ "Gao", "Jun", "" ], [ "Li", "Chong Sheng", "" ], [ "Liu", "Ze Long", "" ], [ "Zhu", "Hua Xing", "" ] ]
We present a fully differential next-to-next-to-leading order calculation of charm quark production in charged-current deep-inelastic scattering, with full charm-quark mass dependence. The next-to-next-to-leading order corrections in perturbative quantum chromodynamics are found to be comparable in size to the next-to-leading order corrections in certain kinematic regions. We compare our predictions with data on dimuon production in (anti-)neutrino scattering from a heavy nucleus. Our results can be used to improve the extraction of the parton distribution function of a strange quark in the nucleon.
2310.02672
Maxim Malyshev
A. V. Lipatov, G. I. Lykasov, M. A. Malyshev
Self-consistent description of HERA data at low $Q^2$ and soft hadron production at LHC
12 pages, 6 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Using the analytical expression for transverse momentum dependent (TMD) gluon density in a proton, a self-consistent simultaneous description of low $Q^2$ data on proton structure function $F_2(x,Q^2)$, reduced cross section for the electron-proton deep inelastic scattering at HERA and soft hadron production in $pp$ collisions at the LHC is achieved in the framework of color dipole approach and modified quark-gluon string model.
[ { "created": "Wed, 4 Oct 2023 09:21:41 GMT", "version": "v1" }, { "created": "Thu, 5 Oct 2023 08:57:47 GMT", "version": "v2" } ]
2023-10-06
[ [ "Lipatov", "A. V.", "" ], [ "Lykasov", "G. I.", "" ], [ "Malyshev", "M. A.", "" ] ]
Using the analytical expression for transverse momentum dependent (TMD) gluon density in a proton, a self-consistent simultaneous description of low $Q^2$ data on proton structure function $F_2(x,Q^2)$, reduced cross section for the electron-proton deep inelastic scattering at HERA and soft hadron production in $pp$ collisions at the LHC is achieved in the framework of color dipole approach and modified quark-gluon string model.
2112.03892
Raghunath Sahoo
Suraj Prasad, Neelkamal Mallick, Debadatta Behera, Raghunath Sahoo, and Sushanta Tripathy
Event topology and global observables in heavy-ion collisions at the Large Hadron Collider
Same as the published version
Sci Rep 12, 3917 (2022)
10.1038/s41598-022-07547-z
null
hep-ph hep-ex nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
Particle production and event topology are very strongly correlated in high-energy hadronic and nuclear collisions. Event topology is decided by the underlying particle production dynamics and medium effects. Transverse spherocity is an event shape observable, which has been used in pp and heavy-ion collisions to separate the events based on their geometrical shapes. It has the unique capability to distinguish between jetty and isotropic events. In this work, we have implemented transverse spherocity in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV using A Multi-Phase Transport Model (AMPT). While awaiting for experimental explorations, we perform a feasibility study of dependence of transverse spherocity on some of the global observables in heavy-ion collisions at the Large Hadron Collider energies. These global observables include the Bjorken energy density ($\epsilon_{\rm B_j}$), speed of sound ($c_{\rm s}^2$) in the medium and the kinetic freeze-out properties for different collision centralities. The present study reveals about the usefulness of event topology dependent measurements in heavy-ion collisions in contrast to proton-proton collisions.
[ { "created": "Tue, 7 Dec 2021 18:38:43 GMT", "version": "v1" }, { "created": "Thu, 10 Mar 2022 15:19:18 GMT", "version": "v2" } ]
2022-03-11
[ [ "Prasad", "Suraj", "" ], [ "Mallick", "Neelkamal", "" ], [ "Behera", "Debadatta", "" ], [ "Sahoo", "Raghunath", "" ], [ "Tripathy", "Sushanta", "" ] ]
Particle production and event topology are very strongly correlated in high-energy hadronic and nuclear collisions. Event topology is decided by the underlying particle production dynamics and medium effects. Transverse spherocity is an event shape observable, which has been used in pp and heavy-ion collisions to separate the events based on their geometrical shapes. It has the unique capability to distinguish between jetty and isotropic events. In this work, we have implemented transverse spherocity in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV using A Multi-Phase Transport Model (AMPT). While awaiting for experimental explorations, we perform a feasibility study of dependence of transverse spherocity on some of the global observables in heavy-ion collisions at the Large Hadron Collider energies. These global observables include the Bjorken energy density ($\epsilon_{\rm B_j}$), speed of sound ($c_{\rm s}^2$) in the medium and the kinetic freeze-out properties for different collision centralities. The present study reveals about the usefulness of event topology dependent measurements in heavy-ion collisions in contrast to proton-proton collisions.
hep-ph/0703168
Masaoki Kusunoki
S. Fleming, M. Kusunoki, T. Mehen, and U. van Kolck
Pion Interactions in the X(3872)
26 pages, 11 figures, revtex4, to appear in Phys. Rev. D
Phys.Rev.D76:034006,2007
10.1103/PhysRevD.76.034006
null
hep-ph hep-ex nucl-th
null
We consider pion interactions in an effective field theory of the narrow resonance X(3872), assuming it is a weakly bound molecule of the charm mesons D^{0} \bar D^{*0} and D^{*0} \bar D^{0}. Since the hyperfine splitting of the D^{0} and D^{*0} is only 7 MeV greater than the neutral pion mass, pions can be produced near threshold and are non-relativistic. We show that pion exchange can be treated in perturbation theory and calculate the next-to-leading-order correction to the partial decay width \Gamma[X \to D^0 \bar D^{0} \pi^0].
[ { "created": "Fri, 16 Mar 2007 04:03:00 GMT", "version": "v1" }, { "created": "Tue, 5 Jun 2007 06:59:32 GMT", "version": "v2" } ]
2008-11-26
[ [ "Fleming", "S.", "" ], [ "Kusunoki", "M.", "" ], [ "Mehen", "T.", "" ], [ "van Kolck", "U.", "" ] ]
We consider pion interactions in an effective field theory of the narrow resonance X(3872), assuming it is a weakly bound molecule of the charm mesons D^{0} \bar D^{*0} and D^{*0} \bar D^{0}. Since the hyperfine splitting of the D^{0} and D^{*0} is only 7 MeV greater than the neutral pion mass, pions can be produced near threshold and are non-relativistic. We show that pion exchange can be treated in perturbation theory and calculate the next-to-leading-order correction to the partial decay width \Gamma[X \to D^0 \bar D^{0} \pi^0].
1204.6327
Jose L. Goity
Jose L. Goity and Roberto C. Trinchero
Holographic models and the QCD trace anomaly
18 pages 1 figure In this revised version, the section on the analysis of the Wilson loop was improved, and a section was added on the matching of the calculations of the gluon condensate via the d+1 dim action and the Wilson loop
null
10.1103/PhysRevD.86.034033
JLAB-THY-12-1514
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Five dimensional dilaton models are considered as possible holographic duals of the pure gauge QCD vacuum. In the framework of these models, the QCD trace anomaly equation is considered. Each quantity appearing in that equation is computed by holographic means. Two exact solutions for different dilaton potentials corresponding to perturbative and non-perturbative beta-functions are studied. It is shown that in the perturbative case, where the beta-function is the QCD one at leading order, the resulting space is not asymptotically AdS. In the non-perturbative case, the model considered presents confinement of static quarks and leads to a non-vanishing gluon condensate, although it does not correspond to an asymptotically free theory. In both cases analyses based on the trace anomaly and on Wilson loops are carried out.
[ { "created": "Fri, 27 Apr 2012 20:29:49 GMT", "version": "v1" }, { "created": "Sat, 8 Sep 2012 17:05:09 GMT", "version": "v2" } ]
2015-06-04
[ [ "Goity", "Jose L.", "" ], [ "Trinchero", "Roberto C.", "" ] ]
Five dimensional dilaton models are considered as possible holographic duals of the pure gauge QCD vacuum. In the framework of these models, the QCD trace anomaly equation is considered. Each quantity appearing in that equation is computed by holographic means. Two exact solutions for different dilaton potentials corresponding to perturbative and non-perturbative beta-functions are studied. It is shown that in the perturbative case, where the beta-function is the QCD one at leading order, the resulting space is not asymptotically AdS. In the non-perturbative case, the model considered presents confinement of static quarks and leads to a non-vanishing gluon condensate, although it does not correspond to an asymptotically free theory. In both cases analyses based on the trace anomaly and on Wilson loops are carried out.
1212.3313
Dremin
I.M. Dremin, V.A. Nechitailo
Testing scaling laws for the elastic scattering of protons
9 pages, 4 figures
null
10.1016/j.physletb.2013.02.012
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Theoretical proposals of scaling laws for the differential elastic scattering cross sections of protons are confronted with experimental data over a wide energy range. Different combinations of the transferred momentum and energy resulting from the solution of the definite partial differential equation are attempted as scaling variables. Reasonable scaling of the differential cross sections in the diffraction cone has been shown for one of these variables. The violation of the geometrical scaling is ascribed to the increase of the proton blackness with energy. The origin of high-t region violations of scaling laws is discussed.
[ { "created": "Thu, 13 Dec 2012 20:47:03 GMT", "version": "v1" } ]
2015-06-12
[ [ "Dremin", "I. M.", "" ], [ "Nechitailo", "V. A.", "" ] ]
Theoretical proposals of scaling laws for the differential elastic scattering cross sections of protons are confronted with experimental data over a wide energy range. Different combinations of the transferred momentum and energy resulting from the solution of the definite partial differential equation are attempted as scaling variables. Reasonable scaling of the differential cross sections in the diffraction cone has been shown for one of these variables. The violation of the geometrical scaling is ascribed to the increase of the proton blackness with energy. The origin of high-t region violations of scaling laws is discussed.
hep-ph/0612129
Sergey Gevorkyan
S.R.Gevorkyan, A.V.Tarasov, O.O.Voskresenskaya
Electromagnetic corrections to final state interactions in $K\to 3\pi $ decays
7 pages,1 figure
Phys.Lett.B649:159-161,2007
10.1016/j.physletb.2007.04.015
null
hep-ph
null
The final state interactions of pions in decays $K^\pm\to\pi^\pm\pi^0\pi^0$ are considered using the methods of quantum mechanics. We show how to incorporate the electromagnetic effects in the amplitudes of these decays and to work out the relevant expressions valid above and below the two charged pions production threshold $M_c=2m$. The electromagnetic corrections are given as evaluated in a potential model.
[ { "created": "Mon, 11 Dec 2006 14:25:43 GMT", "version": "v1" }, { "created": "Sun, 7 Jan 2007 14:47:39 GMT", "version": "v2" }, { "created": "Wed, 10 Jan 2007 21:23:43 GMT", "version": "v3" }, { "created": "Sat, 3 Feb 2007 20:17:58 GMT", "version": "v4" } ]
2010-10-27
[ [ "Gevorkyan", "S. R.", "" ], [ "Tarasov", "A. V.", "" ], [ "Voskresenskaya", "O. O.", "" ] ]
The final state interactions of pions in decays $K^\pm\to\pi^\pm\pi^0\pi^0$ are considered using the methods of quantum mechanics. We show how to incorporate the electromagnetic effects in the amplitudes of these decays and to work out the relevant expressions valid above and below the two charged pions production threshold $M_c=2m$. The electromagnetic corrections are given as evaluated in a potential model.
1206.0176
Daniele Bettinelli
D. Bettinelli and J. J. van der Bij
Heavy top renormalon contribution to fermion propagators
30 pages, 14 figures, 1 table; v2: Ref.19 added, typos corrected, final version published in PRD
Phys.Rev. D86 (2012) 045018
10.1103/PhysRevD.86.045018
IFUM-996-FT; FR-PHENO-2012-11
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study resummed perturbative contributions due to a heavy top-quark. These renormalon contributions are evaluated for fermion propagators. Results for the top-quark width are given. Estimates of non-perturbative uncertainties are made on the \rho-parameter using different schemes of dealing with the Landau-pole. For the physical top-quark mass the effects are negligible.
[ { "created": "Fri, 1 Jun 2012 13:25:12 GMT", "version": "v1" }, { "created": "Tue, 28 Aug 2012 14:11:18 GMT", "version": "v2" } ]
2012-08-29
[ [ "Bettinelli", "D.", "" ], [ "van der Bij", "J. J.", "" ] ]
We study resummed perturbative contributions due to a heavy top-quark. These renormalon contributions are evaluated for fermion propagators. Results for the top-quark width are given. Estimates of non-perturbative uncertainties are made on the \rho-parameter using different schemes of dealing with the Landau-pole. For the physical top-quark mass the effects are negligible.
0705.0035
Bryan J. Field
B. Field (Florida State), C.B. Jackson (Brookhaven), and L. Reina (Florida State)
Higgs boson production with one bottom quark including higher-order soft-gluon corrections
revtex4, 13 pages, 11 figures; new references and additional comments
Phys.Rev.D76:074008,2007
10.1103/PhysRevD.76.074008
FSU-HEP-2007-0501, BNL-HET-07/7
hep-ph
null
A Higgs boson produced in association with one or more bottom quarks is of great theoretical and experimental interest to the high-energy community. A precise prediction of its total and differential cross-section can have a great impact on the discovery of a Higgs boson with large bottom-quark Yukawa coupling, like the scalar (h^0 and H^0) and pseudoscalar (A^0) Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) in the region of large \tan\beta. In this paper we apply the threshold resummation formalism to determine both differential and total cross-sections for b g \to b\Phi (where \Phi = h^0, H^0), including up to next-to-next-to-next-to-leading order (NNNLO) soft plus virtual QCD corrections at next-to-leading logarithmic (NLL) accuracy. We present results for both the Fermilab Tevatron and the CERN Large Hadron Collider (LHC).
[ { "created": "Tue, 1 May 2007 19:58:20 GMT", "version": "v1" }, { "created": "Thu, 12 Jul 2007 17:09:25 GMT", "version": "v2" } ]
2008-11-26
[ [ "Field", "B.", "", "Florida State" ], [ "Jackson", "C. B.", "", "Brookhaven" ], [ "Reina", "L.", "", "Florida State" ] ]
A Higgs boson produced in association with one or more bottom quarks is of great theoretical and experimental interest to the high-energy community. A precise prediction of its total and differential cross-section can have a great impact on the discovery of a Higgs boson with large bottom-quark Yukawa coupling, like the scalar (h^0 and H^0) and pseudoscalar (A^0) Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) in the region of large \tan\beta. In this paper we apply the threshold resummation formalism to determine both differential and total cross-sections for b g \to b\Phi (where \Phi = h^0, H^0), including up to next-to-next-to-next-to-leading order (NNNLO) soft plus virtual QCD corrections at next-to-leading logarithmic (NLL) accuracy. We present results for both the Fermilab Tevatron and the CERN Large Hadron Collider (LHC).
1104.2680
Terry Mart
T. Mart
Kaon photoproduction and electroproduction near threshold
11 pages, 5 figures, Talk given at Baryons'10: International Conference on the Structure of Baryons, December 7-11, 2010, Osaka, Japan
null
10.1063/1.3647389
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the electromagnetic production of K^+Lambda and K^0Lambda near their production thresholds by using isobar models. In the K^+Lambda channel we show that the model can nicely describe the available experimental data. In the K^0Lambda channel we demonstrate that the K^0 charge form factor has sizable effects on the longitudinal cross section. By extending the model up to W = 1730 MeV, we are able to observe the existence of the narrow P_{11} (J^p = 1/2^+) resonance in the kaon photoproduction process. It is found that the most convincing mass (width) of this resonance is 1650 MeV (5 MeV).
[ { "created": "Thu, 14 Apr 2011 07:00:44 GMT", "version": "v1" } ]
2015-05-27
[ [ "Mart", "T.", "" ] ]
We analyze the electromagnetic production of K^+Lambda and K^0Lambda near their production thresholds by using isobar models. In the K^+Lambda channel we show that the model can nicely describe the available experimental data. In the K^0Lambda channel we demonstrate that the K^0 charge form factor has sizable effects on the longitudinal cross section. By extending the model up to W = 1730 MeV, we are able to observe the existence of the narrow P_{11} (J^p = 1/2^+) resonance in the kaon photoproduction process. It is found that the most convincing mass (width) of this resonance is 1650 MeV (5 MeV).
2211.10210
Komninos-John Plows
Komninos-John Plows and Xianguo Lu
Modelling Heavy Neutral Leptons in Accelerator Beamlines
25 pages, 19 figures. Accepted version by Physical Review D
Phys. Rev. D 107 (2023) 055003
10.1103/PhysRevD.107.055003
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Heavy Neutral Leptons (HNLs) with masses $\mathcal{O}(0.1 - 1\,\,\text{GeV}/c^{2})$ are promising candidates for the simultaneous explanation of the smallness of the observed neutrino masses as well as the matter-antimatter asymmetry in the observable Universe. These particles can be produced in the decay of hadrons typically produced in a neutrino beamline used for oscillation experiments, and have sufficient lifetime to propagate to a near detector, where they decay to observable particles. For the approximation of a single new mass eigenstate mixing with the Standard Model via the lepton mixing matrix, a simulation framework based on the GENIE event generator has been developed. This module is designed to facilitate searches for HNL through a unified, minimal interface employing a detailed treatment of the kinematics and dynamics of massive unstable neutrinos, with a transparently organised suite of physics effects tracking the HNL from its production to its decay. These mechanisms are expounded on in the current work, underlining the rich landscape for novel, non-trivial physics that has already been identified in previous literature. This framework is an ongoing effort to provide a consistent and comprehensive description of heavy neutrinos from particle decays. We highlight use cases and future applications of interest to the accelerator neutrino community.
[ { "created": "Fri, 18 Nov 2022 13:00:58 GMT", "version": "v1" }, { "created": "Mon, 12 Dec 2022 18:13:41 GMT", "version": "v2" }, { "created": "Mon, 27 Feb 2023 18:32:06 GMT", "version": "v3" } ]
2023-03-07
[ [ "Plows", "Komninos-John", "" ], [ "Lu", "Xianguo", "" ] ]
Heavy Neutral Leptons (HNLs) with masses $\mathcal{O}(0.1 - 1\,\,\text{GeV}/c^{2})$ are promising candidates for the simultaneous explanation of the smallness of the observed neutrino masses as well as the matter-antimatter asymmetry in the observable Universe. These particles can be produced in the decay of hadrons typically produced in a neutrino beamline used for oscillation experiments, and have sufficient lifetime to propagate to a near detector, where they decay to observable particles. For the approximation of a single new mass eigenstate mixing with the Standard Model via the lepton mixing matrix, a simulation framework based on the GENIE event generator has been developed. This module is designed to facilitate searches for HNL through a unified, minimal interface employing a detailed treatment of the kinematics and dynamics of massive unstable neutrinos, with a transparently organised suite of physics effects tracking the HNL from its production to its decay. These mechanisms are expounded on in the current work, underlining the rich landscape for novel, non-trivial physics that has already been identified in previous literature. This framework is an ongoing effort to provide a consistent and comprehensive description of heavy neutrinos from particle decays. We highlight use cases and future applications of interest to the accelerator neutrino community.
1702.06353
Marco Stratmann
D. de Florian, M. Epele, R. J. Hernandez-Pinto, R. Sassot, M. Stratmann
Parton-to-Kaon Fragmentation Revisited
14 pages, 10 eps figures. arXiv admin note: substantial text overlap with arXiv:1410.6027
Phys. Rev. D 95, 094019 (2017)
10.1103/PhysRevD.95.094019
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the global QCD analysis of parton-to-kaon fragmentation functions at next-to-leading order accuracy using the latest experimental information on single-inclusive kaon production in electron-positron annihilation, lepton-nucleon deep-inelastic scattering, and proton-proton collisions. An excellent description of all data sets is achieved, and the remaining uncertainties in parton-to-kaon fragmentation functions are estimated and discussed based on the Hessian method. Extensive comparisons to the results from our previous global analysis are made.
[ { "created": "Tue, 21 Feb 2017 12:29:46 GMT", "version": "v1" } ]
2017-05-31
[ [ "de Florian", "D.", "" ], [ "Epele", "M.", "" ], [ "Hernandez-Pinto", "R. J.", "" ], [ "Sassot", "R.", "" ], [ "Stratmann", "M.", "" ] ]
We revisit the global QCD analysis of parton-to-kaon fragmentation functions at next-to-leading order accuracy using the latest experimental information on single-inclusive kaon production in electron-positron annihilation, lepton-nucleon deep-inelastic scattering, and proton-proton collisions. An excellent description of all data sets is achieved, and the remaining uncertainties in parton-to-kaon fragmentation functions are estimated and discussed based on the Hessian method. Extensive comparisons to the results from our previous global analysis are made.
1106.6248
Daniel Boyanovsky
Daniel Boyanovsky
Short baseline neutrino oscillations: when entanglement suppresses coherence
29 pages, 6 figures, revised MiniBooNE estimates, matches published version
Physical Review D 84, 065001 (2011)
10.1103/PhysRevD.84.065001
null
hep-ph hep-ex quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For neutrino oscillations to take place the entangled quantum state of a neutrino and a charged lepton produced via charged current interactions must be disentangled. Implementing a non-perturbative Wigner-Weisskopf method we obtain the correct \emph{entangled} quantum state of neutrinos and charged leptons from the (two-body) decay of a parent particle. The source lifetime and disentanglement length scale lead to a suppression of the oscillation probabilities in short-baseline experiments. The suppression is determined by $\pi\, L_s/L_{osc}$ where $L_s$ is the \emph{smallest} of the decay length of the parent particle or the disentanglement length scale. For $L_s \geq L_{osc}$ coherence and oscillations are suppressed. These effects are more prominent in \emph{short base line experiments} and at low neutrino energy. We obtain the corrections to the appearance and disappearance probabilities modified by both the lifetime of the source and the disentanglement scale and discuss their implications for accelerator and reactor experiments. These effects imply that fits to the experimental data based on the usual quantum mechanical formulation \emph{underestimate} $\sin^2(2\theta)$ and $\delta m^2$, and are more dramatic for $\delta m^2\simeq \,\mathrm{eV}^2$, the mass range for new generations of sterile neutrinos that could explain the short-baseline anomalies.
[ { "created": "Thu, 30 Jun 2011 14:45:44 GMT", "version": "v1" }, { "created": "Thu, 1 Sep 2011 20:04:14 GMT", "version": "v2" } ]
2011-09-05
[ [ "Boyanovsky", "Daniel", "" ] ]
For neutrino oscillations to take place the entangled quantum state of a neutrino and a charged lepton produced via charged current interactions must be disentangled. Implementing a non-perturbative Wigner-Weisskopf method we obtain the correct \emph{entangled} quantum state of neutrinos and charged leptons from the (two-body) decay of a parent particle. The source lifetime and disentanglement length scale lead to a suppression of the oscillation probabilities in short-baseline experiments. The suppression is determined by $\pi\, L_s/L_{osc}$ where $L_s$ is the \emph{smallest} of the decay length of the parent particle or the disentanglement length scale. For $L_s \geq L_{osc}$ coherence and oscillations are suppressed. These effects are more prominent in \emph{short base line experiments} and at low neutrino energy. We obtain the corrections to the appearance and disappearance probabilities modified by both the lifetime of the source and the disentanglement scale and discuss their implications for accelerator and reactor experiments. These effects imply that fits to the experimental data based on the usual quantum mechanical formulation \emph{underestimate} $\sin^2(2\theta)$ and $\delta m^2$, and are more dramatic for $\delta m^2\simeq \,\mathrm{eV}^2$, the mass range for new generations of sterile neutrinos that could explain the short-baseline anomalies.
hep-ph/0611299
Josip Trampetic Dr.
M. Buric, D. Latas, V. Radovanovic, J. Trampetic
Improved Z -> gamma gamma decay in the renormalizable gauge sector of the noncommutative standard model
4 pages
null
10.1103/PhysRevD.75.097701
null
hep-ph hep-th
null
In this work we propose the Z -> gamma gamma decay as a process strictly forbidden in the standard model, suitable for the search of noncommutativity of coordinates at very short distances. We computed the Z -> gamma gamma partial width in the framework of the recently proposed one-loop renormalizable gauge sector of the noncommutative standard model. New experimental possibilities at LHC are analyzed and a firm bound to the scale of noncommutativity parameter is set around 1 TeV.
[ { "created": "Thu, 23 Nov 2006 13:57:21 GMT", "version": "v1" }, { "created": "Mon, 23 Apr 2007 13:57:26 GMT", "version": "v2" } ]
2009-11-11
[ [ "Buric", "M.", "" ], [ "Latas", "D.", "" ], [ "Radovanovic", "V.", "" ], [ "Trampetic", "J.", "" ] ]
In this work we propose the Z -> gamma gamma decay as a process strictly forbidden in the standard model, suitable for the search of noncommutativity of coordinates at very short distances. We computed the Z -> gamma gamma partial width in the framework of the recently proposed one-loop renormalizable gauge sector of the noncommutative standard model. New experimental possibilities at LHC are analyzed and a firm bound to the scale of noncommutativity parameter is set around 1 TeV.
0705.3636
Hooman Davoudiasl
Hooman Davoudiasl
Constraining Unparticle Physics with Cosmology and Astrophysics
4 pages, RevTex4. Two figures and a reference added. Some minor changes. Main results and conclusions unchanged. Version accepted for publication by PRL
Phys.Rev.Lett.99:141301,2007
10.1103/PhysRevLett.99.141301
BNL-HET-07/8
hep-ph astro-ph
null
It has recently been suggested that a scale invariant "unparticle" sector with a non-trivial infrared fixed point may couple to the Standard Model (SM) via higher dimensional operators. The weakness of such interactions hides the the unparticle phenomena at low energies. We demonstrate how cosmology and astrophysics can place significant bounds on the strength of unparticle-SM interactions. We also discuss the possibility of a having a non-negligible unparticle relic density today.
[ { "created": "Thu, 24 May 2007 18:35:31 GMT", "version": "v1" }, { "created": "Thu, 24 May 2007 23:41:20 GMT", "version": "v2" }, { "created": "Wed, 20 Jun 2007 20:26:53 GMT", "version": "v3" }, { "created": "Fri, 21 Sep 2007 15:52:49 GMT", "version": "v4" } ]
2008-11-26
[ [ "Davoudiasl", "Hooman", "" ] ]
It has recently been suggested that a scale invariant "unparticle" sector with a non-trivial infrared fixed point may couple to the Standard Model (SM) via higher dimensional operators. The weakness of such interactions hides the the unparticle phenomena at low energies. We demonstrate how cosmology and astrophysics can place significant bounds on the strength of unparticle-SM interactions. We also discuss the possibility of a having a non-negligible unparticle relic density today.
1204.4523
Teruyuki Kitabayashi
Teruyuki Kitabayashi, Masaki Yasue
Charged lepton contributions to bipair neutrino mixing
8 pages, 1 figures, version to appear in Physics Letters B
null
10.1016/j.physletb.2012.05.050
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The bipair neutrino mixing describes the observed solar and atmospheric mixings; however, it predicts vanishing reactor mixing angle, which is inconsistent with the observed data. We explore the ways of minimally modifying the bipair neutrino mixing by including charged lepton contributions. There are two categories of the bipair neutrino mixing which are referred to as case 1 and case 2. It turns out that, without arbitrary phases, a minimal modification is realized by just considering one $e$ - $\tau$ contribution from the charged lepton sector in the case 1. On the other hand, not only $e$ - $\tau$ contribution but also $\mu$ - $\tau$ contribution is required to realize a minimal modification in the case 2.
[ { "created": "Fri, 20 Apr 2012 03:19:32 GMT", "version": "v1" }, { "created": "Mon, 28 May 2012 08:35:53 GMT", "version": "v2" } ]
2015-06-04
[ [ "Kitabayashi", "Teruyuki", "" ], [ "Yasue", "Masaki", "" ] ]
The bipair neutrino mixing describes the observed solar and atmospheric mixings; however, it predicts vanishing reactor mixing angle, which is inconsistent with the observed data. We explore the ways of minimally modifying the bipair neutrino mixing by including charged lepton contributions. There are two categories of the bipair neutrino mixing which are referred to as case 1 and case 2. It turns out that, without arbitrary phases, a minimal modification is realized by just considering one $e$ - $\tau$ contribution from the charged lepton sector in the case 1. On the other hand, not only $e$ - $\tau$ contribution but also $\mu$ - $\tau$ contribution is required to realize a minimal modification in the case 2.
hep-ph/9707543
null
Stanley J. Brodsky and Patrick Huet
Aspects of SU(N_c) Gauge Theories in the Limit of Small Number of Colors
Contract number added, LaTex, 16 pages
Phys.Lett.B417:145-153,1998
10.1016/S0370-2693(97)01209-4
SLAC-PUB-7603
hep-ph hep-th
null
We investigate properties of the color space of $SU(N_c)$ gauge theories in the limit of small number of colors $(N_c \to 0)$ and large number of flavors. More generally, we introduce a rescaling of $\alpha_s$ and $n_f$ which assigns a finite limit to colored quantities as $N_c \to 0$, which reproduces their known large-$N_c$ limit, and which expresses them as an analytic function of $N_c^2$ for arbitrary value of $N_c$. The vanishing-$N_c$ limit has an Abelian character and is also the small-$N_c$ limit of $[U(1)]^{N_c-1}$. This limit does not have an obvious quantum field theory interpretation; however, it provides practical consistency checks on QCD perturbative quantities by comparing them to their QED counterparts. Our analysis also describes the two-dimensional topological structure involved in the interpretation of the small $N_c$-limit in color space.
[ { "created": "Thu, 31 Jul 1997 22:27:50 GMT", "version": "v1" }, { "created": "Mon, 11 Aug 1997 23:47:49 GMT", "version": "v2" } ]
2009-09-11
[ [ "Brodsky", "Stanley J.", "" ], [ "Huet", "Patrick", "" ] ]
We investigate properties of the color space of $SU(N_c)$ gauge theories in the limit of small number of colors $(N_c \to 0)$ and large number of flavors. More generally, we introduce a rescaling of $\alpha_s$ and $n_f$ which assigns a finite limit to colored quantities as $N_c \to 0$, which reproduces their known large-$N_c$ limit, and which expresses them as an analytic function of $N_c^2$ for arbitrary value of $N_c$. The vanishing-$N_c$ limit has an Abelian character and is also the small-$N_c$ limit of $[U(1)]^{N_c-1}$. This limit does not have an obvious quantum field theory interpretation; however, it provides practical consistency checks on QCD perturbative quantities by comparing them to their QED counterparts. Our analysis also describes the two-dimensional topological structure involved in the interpretation of the small $N_c$-limit in color space.
hep-ph/0505023
Mark Strikman
M. Strikman (PSU, U.S.A.), M. Tverskoy and M. Zhalov (PNPI, Russia)
Neutron tagging of quasielastic J/psi photoproduction off nucleus in ultraperipheral heavy ion collisions at RHIC energies
12 pages, 5 figures
Phys.Lett.B626:72-79,2005
10.1016/j.physletb.2005.08.083
null
hep-ph
null
We compare the coherent and quasielastic J/psi photoproduction in the peripheral heavy ion collisions in kinematics of RHIC. Our improved estimate of the total coherent cross section is a factor of two smaller than the earlier ones. We find that the counting rate of quasielastic J/psi photoproduction tagged by neutrons emitted due to cascading of the recoiled nucleon within the residual nucleus exceeds the rate of the coherent events. We argue that measurements of this process can be used to learn about the dynamics of color dipole-nucleon interactions in nuclei in the wide effective range of energies of gamma A interactions.
[ { "created": "Tue, 3 May 2005 22:39:06 GMT", "version": "v1" } ]
2014-11-18
[ [ "Strikman", "M.", "", "PSU, U.S.A." ], [ "Tverskoy", "M.", "", "PNPI, Russia" ], [ "Zhalov", "M.", "", "PNPI, Russia" ] ]
We compare the coherent and quasielastic J/psi photoproduction in the peripheral heavy ion collisions in kinematics of RHIC. Our improved estimate of the total coherent cross section is a factor of two smaller than the earlier ones. We find that the counting rate of quasielastic J/psi photoproduction tagged by neutrons emitted due to cascading of the recoiled nucleon within the residual nucleus exceeds the rate of the coherent events. We argue that measurements of this process can be used to learn about the dynamics of color dipole-nucleon interactions in nuclei in the wide effective range of energies of gamma A interactions.
hep-ph/9505440
null
Luis M. A. Bettencourt(Imperial)
Coarse-Grained Fluctuation Probabilities in the Standard Model and Subcritical Bubbles
Latex file, 13 pages. 7 figures, available in compressed form by anonymous ftp from ftp://euclid.tp.ph.ic.ac.uk/papers/94-5_38.fig Latex and postscript versions also available at http://euclid.tp.ph.ic.ac.uk/Papers/index.html
Phys.Lett. B356 (1995) 297-306
10.1016/0370-2693(95)00827-8
IMPERIAL/TP/94-95/38
hep-ph
null
We compute systematically the probability for fluctuations of the Higgs field, averaged over a given spatial scale, to exceed a specified value, in the Standard Model. For the particular case of interest of averages over one coherence volume we show that, even in the worst possible case of taking the one-loop improved effective potential parameters, the probability for the field to fluctuate from the symmetric to the asymmetric minimum before the latter becomes stable is very small for Higgs masses of the order of those of the $W$ and $Z$ bosons, whereas the converse is more likely. As such, metastability should be satisfied dynamically at the Electroweak phase transition and its dynamics should therefore proceed by the usual mechanism of bubble nucleation with subcritical fluctuations playing no particularly relevant role in it.
[ { "created": "Wed, 31 May 1995 16:36:43 GMT", "version": "v1" } ]
2009-10-28
[ [ "Bettencourt", "Luis M. A.", "", "Imperial" ] ]
We compute systematically the probability for fluctuations of the Higgs field, averaged over a given spatial scale, to exceed a specified value, in the Standard Model. For the particular case of interest of averages over one coherence volume we show that, even in the worst possible case of taking the one-loop improved effective potential parameters, the probability for the field to fluctuate from the symmetric to the asymmetric minimum before the latter becomes stable is very small for Higgs masses of the order of those of the $W$ and $Z$ bosons, whereas the converse is more likely. As such, metastability should be satisfied dynamically at the Electroweak phase transition and its dynamics should therefore proceed by the usual mechanism of bubble nucleation with subcritical fluctuations playing no particularly relevant role in it.
hep-ph/9411357
Brahmachari Biswajoy
Biswajoy Brahmachari
Predictions of the Top mass in Mininal Supersymmetric Left-Right Model
Revised including new analysis of mb/mtau. This version is to appear
Phys.Rev.D52:1-5,1995
10.1103/PhysRevD.52.1
null
hep-ph
null
The one-loop evolution of Yukawa couplings in the minimal supersymmetric left-right model (MSUSYLR) model with a wide variation of the right handed breaking scale $M_R$ from 1 TeV to $10^{18}$ GeV is studied assuming that all third generation Yukawa couplings are equal and in the fixed point domain of the top quark Yuakwa coupling ($h_t$) at the Plank scale. We show that: (1) The top quark Yukawa coupling $h_t$ displays a fixed point behaviour that is similar to that of the minimal supersymmetric standard model (MSSM). (2) The MSUSYLR model predicts a value of the top mass in the interval 177 to 184 GeV for $\alpha_s$ in the interval 0.11 to 0.12. (3) A large value of $tan\beta$ is required to reproduce the correct mass of the bottom quark and tau lepton. (4) With the experimental value of the ratio ${m_b(m_b) \over m_\tau(m_\tau)}$ as an input the range of the right handed symmetry breaking scale $M_R$ can be predicted. (5) The numerical value of the Majorana Yukawa coupling $h_M$ can be calculated which is otherwise a completely free parameter.
[ { "created": "Tue, 22 Nov 1994 12:44:24 GMT", "version": "v1" }, { "created": "Sat, 13 May 1995 19:25:39 GMT", "version": "v2" } ]
2010-01-06
[ [ "Brahmachari", "Biswajoy", "" ] ]
The one-loop evolution of Yukawa couplings in the minimal supersymmetric left-right model (MSUSYLR) model with a wide variation of the right handed breaking scale $M_R$ from 1 TeV to $10^{18}$ GeV is studied assuming that all third generation Yukawa couplings are equal and in the fixed point domain of the top quark Yuakwa coupling ($h_t$) at the Plank scale. We show that: (1) The top quark Yukawa coupling $h_t$ displays a fixed point behaviour that is similar to that of the minimal supersymmetric standard model (MSSM). (2) The MSUSYLR model predicts a value of the top mass in the interval 177 to 184 GeV for $\alpha_s$ in the interval 0.11 to 0.12. (3) A large value of $tan\beta$ is required to reproduce the correct mass of the bottom quark and tau lepton. (4) With the experimental value of the ratio ${m_b(m_b) \over m_\tau(m_\tau)}$ as an input the range of the right handed symmetry breaking scale $M_R$ can be predicted. (5) The numerical value of the Majorana Yukawa coupling $h_M$ can be calculated which is otherwise a completely free parameter.
1903.04905
Claudio O. Dib
Claudio O. Dib, Choong Sun Kim, Sebastian Tapia Araya
Search for light sterile neutrinos from $W^\pm$ decays at the LHC
18 pages, 7 figures. arXiv admin note: text overlap with arXiv:1801.03624
Phys. Rev. D 101, 035022 (2020)
10.1103/PhysRevD.101.035022
NCTS-PH/1801
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the feasibility to observe sterile neutrinos with masses in the range 5 GeV $< m_N < 20$ GeV at the LHC, using exclusive semileptonic modes involving pions, $W\to \ell N \to \pi \ell\ell, 2\pi \ell\ell$ and $3\pi \ell\ell$. We thus cover a mass window that is between what can be studied in meson factories and high energy colliders. We run simulations for these exclusive events, where pions should be distinguished from the background provided the neutrino decay exhibits a vertex displacement from its production point. In a previous work we have estimated the theoretical rates and here we analyze the observability of the processes at the LHC, given the fact that exclusive hadronic states may be difficult to identify. We study the sensitivity bounds for the observation and discovery of sterile neutrinos in the above mass range. By the end of Run-3, current bounds on heavy-to-light lepton mixings in the lower mass end ($\sim 5$ GeV) could be improved by about an order of magnitude to $|U_{\ell N}|^2\sim 5\times 10^{-6}$, and the High-Luminosity LHC could reach $|U_{\ell N}|^2 \lesssim 3\times 10^{-7}$ in the mass range below 11 GeV. Studying in addition equal sign and opposite sign dileptons, the Majorana or Dirac character of the sterile neutrino could be revealed.
[ { "created": "Sun, 10 Mar 2019 01:02:46 GMT", "version": "v1" }, { "created": "Fri, 15 Mar 2019 11:28:20 GMT", "version": "v2" }, { "created": "Mon, 23 Dec 2019 15:01:25 GMT", "version": "v3" }, { "created": "Tue, 11 Feb 2020 17:43:14 GMT", "version": "v4" } ]
2020-02-26
[ [ "Dib", "Claudio O.", "" ], [ "Kim", "Choong Sun", "" ], [ "Araya", "Sebastian Tapia", "" ] ]
We study the feasibility to observe sterile neutrinos with masses in the range 5 GeV $< m_N < 20$ GeV at the LHC, using exclusive semileptonic modes involving pions, $W\to \ell N \to \pi \ell\ell, 2\pi \ell\ell$ and $3\pi \ell\ell$. We thus cover a mass window that is between what can be studied in meson factories and high energy colliders. We run simulations for these exclusive events, where pions should be distinguished from the background provided the neutrino decay exhibits a vertex displacement from its production point. In a previous work we have estimated the theoretical rates and here we analyze the observability of the processes at the LHC, given the fact that exclusive hadronic states may be difficult to identify. We study the sensitivity bounds for the observation and discovery of sterile neutrinos in the above mass range. By the end of Run-3, current bounds on heavy-to-light lepton mixings in the lower mass end ($\sim 5$ GeV) could be improved by about an order of magnitude to $|U_{\ell N}|^2\sim 5\times 10^{-6}$, and the High-Luminosity LHC could reach $|U_{\ell N}|^2 \lesssim 3\times 10^{-7}$ in the mass range below 11 GeV. Studying in addition equal sign and opposite sign dileptons, the Majorana or Dirac character of the sterile neutrino could be revealed.
hep-ph/9305347
Taekoon
Taekoon Lee
Heavy Fermion Production and the Symmetry Breaking Sector of the Electroweak Interactions
17, CU-TP-589
Phys.Lett. B315 (1993) 392-398
10.1016/0370-2693(93)91630-6
null
hep-ph
null
We point out that heavy fermion production through the fusion of the longitudinal gauge bosons might be relevant in probing the strongly interacting symmetry breaking sector of the electroweak interactions, by showing the dependence of the one loop amplititude for ($ w^{+} w^{-} \rightarrow \overline{t} t $) on the symmetry breaking mechanism. The one loop amplitude for ($ w^{+} w^{-} \rightarrow \overline{t} t $) is calculated for the standard model and extended technicolour theory. Techni-rho meson exchange is also briefly discussed. We find at $m_{t} = 150 ~GeV$ the cross section of top pair production in $ e^{+} e^{-}$ collisions is comparable in order of magnitude to that of the longitudinal gauge boson scattering.
[ { "created": "Sat, 29 May 1993 17:35:14 GMT", "version": "v1" }, { "created": "Tue, 1 Jun 1993 16:34:04 GMT", "version": "v2" } ]
2009-10-22
[ [ "Lee", "Taekoon", "" ] ]
We point out that heavy fermion production through the fusion of the longitudinal gauge bosons might be relevant in probing the strongly interacting symmetry breaking sector of the electroweak interactions, by showing the dependence of the one loop amplititude for ($ w^{+} w^{-} \rightarrow \overline{t} t $) on the symmetry breaking mechanism. The one loop amplitude for ($ w^{+} w^{-} \rightarrow \overline{t} t $) is calculated for the standard model and extended technicolour theory. Techni-rho meson exchange is also briefly discussed. We find at $m_{t} = 150 ~GeV$ the cross section of top pair production in $ e^{+} e^{-}$ collisions is comparable in order of magnitude to that of the longitudinal gauge boson scattering.
hep-ph/9802236
Wu Ning
Ning Wu
Gauge Field Model With Massive Gauge Bosons
5 Pages, no figures, LaTex file
null
null
null
hep-ph
null
A gauge field model, which simultaneously has strict local gauge symmetry and massive gauge bosons, is discussed in this paper. The model has SU(N) gauge symmetry. In the limit $\alpha \longrightarrow 0$, the gauge field model discussed in this paper will return to Yang-Mills gauge field model. The important meaning of this model is that, without Higgs mechanism, gauge bosons can also obtain masses. This theory can also explain some other unknown phenomenum.
[ { "created": "Wed, 4 Feb 1998 01:32:32 GMT", "version": "v1" } ]
2007-05-23
[ [ "Wu", "Ning", "" ] ]
A gauge field model, which simultaneously has strict local gauge symmetry and massive gauge bosons, is discussed in this paper. The model has SU(N) gauge symmetry. In the limit $\alpha \longrightarrow 0$, the gauge field model discussed in this paper will return to Yang-Mills gauge field model. The important meaning of this model is that, without Higgs mechanism, gauge bosons can also obtain masses. This theory can also explain some other unknown phenomenum.
2110.03711
Iv\'an Pacheco
Iv\'an Pacheco and Pablo Roig
Lepton flavor violation in the Littlest Higgs Model with T parity realizing an inverse seesaw
41 pages, 19 figures, 3 tables
JHEP02(2022)054
10.1007/JHEP02(2022)054
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study lepton flavor violation (LFV) within the Littlest Higgs Model with T parity (LHT) realizing an inverse seesaw (ISS) mechanism of type I. With respect to the traditional LHT, there appear new $\mathcal{O}$(\textcolor{black}{10} TeV) Majorana neutrinos, driving LFV. For $\tau\to\ell\ell'\bar{\ell}"$ (including wrong-sign, $\ell=e, \mu$) decays and $\mu\to e$ conversion in Ti, we get typical rates only one order of magnitude below present bounds ($\ell\to\ell'\gamma$ can reach the current upper limit) and for $Z\to\bar{\tau}\ell$, $\mu\to e e \bar{e}$ and conversion in Au, results are within two orders of magnitude from present limits. Correlations among modes are drastically different to the traditional LHT and other models, which would ease the confrontation of this scenario to eventual measurements of LFV processes involving charged leptons.
[ { "created": "Thu, 7 Oct 2021 18:01:18 GMT", "version": "v1" }, { "created": "Thu, 27 Jan 2022 22:00:51 GMT", "version": "v2" } ]
2022-02-10
[ [ "Pacheco", "Iván", "" ], [ "Roig", "Pablo", "" ] ]
We study lepton flavor violation (LFV) within the Littlest Higgs Model with T parity (LHT) realizing an inverse seesaw (ISS) mechanism of type I. With respect to the traditional LHT, there appear new $\mathcal{O}$(\textcolor{black}{10} TeV) Majorana neutrinos, driving LFV. For $\tau\to\ell\ell'\bar{\ell}"$ (including wrong-sign, $\ell=e, \mu$) decays and $\mu\to e$ conversion in Ti, we get typical rates only one order of magnitude below present bounds ($\ell\to\ell'\gamma$ can reach the current upper limit) and for $Z\to\bar{\tau}\ell$, $\mu\to e e \bar{e}$ and conversion in Au, results are within two orders of magnitude from present limits. Correlations among modes are drastically different to the traditional LHT and other models, which would ease the confrontation of this scenario to eventual measurements of LFV processes involving charged leptons.
hep-ph/9311263
null
S.Ambrosanio and B.Mele
Single Top Production at the Next Generation Linear e+e- Colliders
20 pages, LaTeX + feynman.tex, 10 compressed (tar.Z) postscript figures included in a separate uuencoded file, revised version of Rome1 Preprint n.979 (1993), Dec 29, 1993. (In this revised version -- accepted for publication on Zeit. fur Phys.C in Jan 24, 1994 -- some sentences and 3 new refs. have been added with respect to the first one)
Z.Phys. C63 (1994) 63-70
10.1007/BF01577544
null
hep-ph
null
Present limits on the top mass from LEP1 and Tevatron point to a top quark that is considerably heavier than the $W$ vector boson in the standard model. Hence, e+e- colliders with \sqrt{s} \simeq 300 GeV (the c.m. energy foreseen at the first phase of the Next Linear e+e- Collider) could be well below the energy threshold for real top-pair production. We argue that, if this is the case, single top production through the process e+e- --> t\bar{b}W- (\bar{t}bW+), where t\bar{b} (\bar{t}b) are produced mainly by means of a virtual W, becomes the dominant top production mechanism. Total cross sections and kinematical distributions are evaluated and numerical results are given in ranges of m_t and \sqrts{s} where single top production can be of relevance. The relative importance of virtual-W and virtual-t contributions to the process is discussed.
[ { "created": "Wed, 10 Nov 1993 15:57:02 GMT", "version": "v1" }, { "created": "Thu, 27 Jan 1994 12:36:00 GMT", "version": "v2" }, { "created": "Sat, 29 Jan 1994 12:30:46 GMT", "version": "v3" } ]
2009-10-22
[ [ "Ambrosanio", "S.", "" ], [ "Mele", "B.", "" ] ]
Present limits on the top mass from LEP1 and Tevatron point to a top quark that is considerably heavier than the $W$ vector boson in the standard model. Hence, e+e- colliders with \sqrt{s} \simeq 300 GeV (the c.m. energy foreseen at the first phase of the Next Linear e+e- Collider) could be well below the energy threshold for real top-pair production. We argue that, if this is the case, single top production through the process e+e- --> t\bar{b}W- (\bar{t}bW+), where t\bar{b} (\bar{t}b) are produced mainly by means of a virtual W, becomes the dominant top production mechanism. Total cross sections and kinematical distributions are evaluated and numerical results are given in ranges of m_t and \sqrts{s} where single top production can be of relevance. The relative importance of virtual-W and virtual-t contributions to the process is discussed.
1105.0308
Mattias Blennow
Carl Blaksley, Mattias Blennow, Florian Bonnet, Pilar Coloma, Enrique Fernandez-Martinez
Heavy Neutrinos and Lepton Number Violation in lp Colliders
18 pages, 5 figures, REVTeX4
null
10.1016/j.nuclphysb.2011.06.021
CERN-PH-TH/2011-094, EURONU-WP6-11-32, IFT-UAM/CSIC-11-25, MPP-2011-50
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the prospects of studying lepton number violating processes in order to identify Majorana neutrinos from low scale seesaw mechanisms at lepton-proton colliders. In particular, we consider the scenarios of colliding electrons with LHC energy protons and, motivated by the efforts towards the construction of a muon collider, the prospects of muon-proton collisions. We find that present constraints on the mixing of the Majorana neutrinos still allow for a detectable signal at these kind of facilities given the smallness of the Standard Model background. We discuss possible cuts in order to further increase the signal over background ratio and the prospects of reconstructing the neutrino mass from the kinematics of the final state particles.
[ { "created": "Mon, 2 May 2011 12:24:02 GMT", "version": "v1" } ]
2014-01-14
[ [ "Blaksley", "Carl", "" ], [ "Blennow", "Mattias", "" ], [ "Bonnet", "Florian", "" ], [ "Coloma", "Pilar", "" ], [ "Fernandez-Martinez", "Enrique", "" ] ]
We discuss the prospects of studying lepton number violating processes in order to identify Majorana neutrinos from low scale seesaw mechanisms at lepton-proton colliders. In particular, we consider the scenarios of colliding electrons with LHC energy protons and, motivated by the efforts towards the construction of a muon collider, the prospects of muon-proton collisions. We find that present constraints on the mixing of the Majorana neutrinos still allow for a detectable signal at these kind of facilities given the smallness of the Standard Model background. We discuss possible cuts in order to further increase the signal over background ratio and the prospects of reconstructing the neutrino mass from the kinematics of the final state particles.
1902.03395
Junxu Lu
Junxu Lu (1 and 2), Lisheng Geng (1), Xiulei Ren (3), Menglin Du (4) ((1) Nuclear Energy Engineering and International Research Center for Nuclei and Particles in the Cosmos Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing, China, (2) Groupe de Physique Th\'eorique, IPN, Universit\'e Paris-Sud 11, Orsay, France, (3) Institut f\"ur Theoretische Physik II, Ruhr-Universit\"at Bochum, (4) Helmholtz-Institut f\"ur Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universit\"at Bonn)
Meson-baryon Scattering in Extend-on-mass-shell scheme at $\mathcal{O}(p^3)$
4 pages, 2 figures, presented by Junxu Lu at the 22th International Conference on Few-Body Problems in Physics, 9 - 13 July, 2018, Caen, France
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this present work, we study the scattering of a pseudoscalar meson off one ground state octet baryon in covariant baryon chiral perturbation theory up to the next-to-next-to-leading order. We remove the power counting breaking terms with the extended-on-mass-shell scheme. We perform the first combined study of the pion-nucleon and kaon-nucleon scattering data and show that the covariant baryon Chiral perturbation theory can provide a reasonable description of the experimental data for both channels.
[ { "created": "Sat, 9 Feb 2019 09:33:07 GMT", "version": "v1" }, { "created": "Tue, 12 Feb 2019 14:09:42 GMT", "version": "v2" } ]
2019-02-13
[ [ "Lu", "Junxu", "", "1 and 2" ], [ "Geng", "Lisheng", "" ], [ "Ren", "Xiulei", "" ], [ "Du", "Menglin", "" ] ]
In this present work, we study the scattering of a pseudoscalar meson off one ground state octet baryon in covariant baryon chiral perturbation theory up to the next-to-next-to-leading order. We remove the power counting breaking terms with the extended-on-mass-shell scheme. We perform the first combined study of the pion-nucleon and kaon-nucleon scattering data and show that the covariant baryon Chiral perturbation theory can provide a reasonable description of the experimental data for both channels.
1401.3689
Stephan Narison
Stephan Narison (LUPM-CNRS-Montpellier, France)
Improved light quark masses from pseudoscalar sum rules
16 pages, 18 figures, 3 tables. Strongly improved version. Some comments and references added. Extended discussions. Slight changes in the values of the light quark masses
null
10.1016/j.physletb.2014.09.056
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using ratios of the inverse Laplace transform sum rules within stability criteria for the subtraction point \mu in addition to the ones of the usual tau spectral sum rule variable and continuum threshold t_c, we extract the \pi(1300) and K(1460) decay constants to order \alpha_s^4 of perturbative QCD by including power corrections up to dimension-six condensates, tachyonic gluon mass, instanton and finite width corrections. Using these inputs with enlarged generous errors, we extract, in a model-independent and conservative ways, the sum of the scale-independent renormalization group invariant (RGI) quark masses (m_u+ m_q):q\equiv d,s and the corresponding running masses (m_u+m_q) evaluated at 2 GeV. By giving the value of the ratio m_u/m_d, we deduce the running quark masses m_{u,d,s} and condensate <\bar uu> and the scale-independent mass ratios : 2m_s/(m_u+m_d) and m_s/m_d. Using the positivity of the QCD continuum contribution to the spectral function, we also deduce, from the inverse Laplace transform sum rules, for the first time to order \alpha_s^4, new lower bounds on the RGI masses which are translated into the running masses at 2 GeV and into upper bounds on the running quark condensate <\bar uu>. Our results summarized in Table 2 and compared with our previous results and with recent lattice averages suggest that precise phenomenological determinations of the sum of light quark masses require improved experimental measurements of the \pi(1.3) and K(1.46) hadronic widths and/or decay constants which are the dominant sources of errors in the analysis.
[ { "created": "Wed, 15 Jan 2014 17:58:56 GMT", "version": "v1" }, { "created": "Thu, 16 Jan 2014 18:45:58 GMT", "version": "v2" }, { "created": "Wed, 27 Aug 2014 15:19:25 GMT", "version": "v3" } ]
2014-10-07
[ [ "Narison", "Stephan", "", "LUPM-CNRS-Montpellier, France" ] ]
Using ratios of the inverse Laplace transform sum rules within stability criteria for the subtraction point \mu in addition to the ones of the usual tau spectral sum rule variable and continuum threshold t_c, we extract the \pi(1300) and K(1460) decay constants to order \alpha_s^4 of perturbative QCD by including power corrections up to dimension-six condensates, tachyonic gluon mass, instanton and finite width corrections. Using these inputs with enlarged generous errors, we extract, in a model-independent and conservative ways, the sum of the scale-independent renormalization group invariant (RGI) quark masses (m_u+ m_q):q\equiv d,s and the corresponding running masses (m_u+m_q) evaluated at 2 GeV. By giving the value of the ratio m_u/m_d, we deduce the running quark masses m_{u,d,s} and condensate <\bar uu> and the scale-independent mass ratios : 2m_s/(m_u+m_d) and m_s/m_d. Using the positivity of the QCD continuum contribution to the spectral function, we also deduce, from the inverse Laplace transform sum rules, for the first time to order \alpha_s^4, new lower bounds on the RGI masses which are translated into the running masses at 2 GeV and into upper bounds on the running quark condensate <\bar uu>. Our results summarized in Table 2 and compared with our previous results and with recent lattice averages suggest that precise phenomenological determinations of the sum of light quark masses require improved experimental measurements of the \pi(1.3) and K(1.46) hadronic widths and/or decay constants which are the dominant sources of errors in the analysis.
1811.05183
Jeong-Yeon Lee Dr.
Jeong-Yeon Lee, Yeongduk Kim, Satoshi Chiba
New targets for relic antineutrino capture
9 pages, 5 figures
Nuclear Physics A 1031 (2023) 122594
10.1016/j.nuclphysa.2022.122594
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
$^{163}$Ho has been considered as a suitable candidate for the capture of relic antineutrinos. However, the detection of the relic antineutrino using $^{163}$Ho is extremely challenging with current techniques. Therefore, we have searched for new targets for relic antineutrino detections through the resonant capture on nuclides undergoing electron capture. We have investigated nuclear and atomic properties of all nuclides. And we finally propose $^{131}$Ba, $^{159}$Dy, $^{175}$Hf, $^{195}$Au, and $^{243}$Cm as new candidates for the relic antineutrino detection, and call for high precise experiments of $Q_{\rm EC}$-values and intensities of EC decays for these new candidates.
[ { "created": "Tue, 13 Nov 2018 09:50:09 GMT", "version": "v1" }, { "created": "Wed, 27 Nov 2019 09:13:22 GMT", "version": "v2" }, { "created": "Tue, 17 Jan 2023 17:27:16 GMT", "version": "v3" } ]
2023-01-18
[ [ "Lee", "Jeong-Yeon", "" ], [ "Kim", "Yeongduk", "" ], [ "Chiba", "Satoshi", "" ] ]
$^{163}$Ho has been considered as a suitable candidate for the capture of relic antineutrinos. However, the detection of the relic antineutrino using $^{163}$Ho is extremely challenging with current techniques. Therefore, we have searched for new targets for relic antineutrino detections through the resonant capture on nuclides undergoing electron capture. We have investigated nuclear and atomic properties of all nuclides. And we finally propose $^{131}$Ba, $^{159}$Dy, $^{175}$Hf, $^{195}$Au, and $^{243}$Cm as new candidates for the relic antineutrino detection, and call for high precise experiments of $Q_{\rm EC}$-values and intensities of EC decays for these new candidates.
1507.02599
Jozef Dudek
David J. Wilson, Raul A. Briceno, Jozef J. Dudek, Robert G. Edwards and Christopher E. Thomas
Coupled $\pi\pi, K\overline{K}$ scattering in $P$-wave and the $\rho$ resonance from lattice QCD
matches published version, minor typos corrected
Phys. Rev. D 92, 094502 (2015)
10.1103/PhysRevD.92.094502
JLAB-THY-15-2101
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We determine elastic and coupled-channel amplitudes for isospin-1 meson-meson scattering in $P$-wave, by calculating correlation functions using lattice QCD with light quark masses such that $m_\pi = 236$ MeV in a cubic volume of $\sim (4 \,\mathrm{fm})^3$. Variational analyses of large matrices of correlation functions computed using operator constructions resembling $\pi\pi$, $K\overline{K}$ and $q\bar{q}$, in several moving frames and several lattice irreducible representations, leads to discrete energy spectra from which scattering amplitudes are extracted. In the elastic $\pi\pi$ scattering region we obtain a detailed energy-dependence for the phase-shift, corresponding to a $\rho$ resonance, and we extend the analysis into the coupled-channel $K\overline{K}$ region for the first time, finding a small coupling between the channels.
[ { "created": "Thu, 9 Jul 2015 17:06:39 GMT", "version": "v1" }, { "created": "Mon, 2 Nov 2015 18:42:30 GMT", "version": "v2" } ]
2015-11-11
[ [ "Wilson", "David J.", "" ], [ "Briceno", "Raul A.", "" ], [ "Dudek", "Jozef J.", "" ], [ "Edwards", "Robert G.", "" ], [ "Thomas", "Christopher E.", "" ] ]
We determine elastic and coupled-channel amplitudes for isospin-1 meson-meson scattering in $P$-wave, by calculating correlation functions using lattice QCD with light quark masses such that $m_\pi = 236$ MeV in a cubic volume of $\sim (4 \,\mathrm{fm})^3$. Variational analyses of large matrices of correlation functions computed using operator constructions resembling $\pi\pi$, $K\overline{K}$ and $q\bar{q}$, in several moving frames and several lattice irreducible representations, leads to discrete energy spectra from which scattering amplitudes are extracted. In the elastic $\pi\pi$ scattering region we obtain a detailed energy-dependence for the phase-shift, corresponding to a $\rho$ resonance, and we extend the analysis into the coupled-channel $K\overline{K}$ region for the first time, finding a small coupling between the channels.
hep-ph/0005026
Marina Nielsen
F.S. Navarra, M. Nielsen, M.E. Bracco, M. Chiapparini and C. L. Schat
$D^*D\pi$ and $B^*B\pi$ form factors from QCD Sum Rules
12 pages, RevTeX including 6 figures in ps files, revised version accepted for publication in Phys. Lett. B
Phys.Lett. B489 (2000) 319-328
10.1016/S0370-2693(00)00967-9
null
hep-ph nucl-th
null
The $H^*H\pi$ form factor for H = B and D mesons is evaluated in a QCD sum rule calculation. We study the Borel sum rule for the three point function of two pseudoscalar and one vector meson currents up to order four in the operator product expansion. The double Borel transform is performed with respect to the heavy meson momenta. We discuss the momentum dependence of the form factors and two different approaches to extract the $H^*H\pi$ coupling constant.
[ { "created": "Wed, 3 May 2000 18:59:24 GMT", "version": "v1" }, { "created": "Thu, 4 May 2000 14:41:29 GMT", "version": "v2" }, { "created": "Thu, 10 Aug 2000 14:36:28 GMT", "version": "v3" } ]
2009-10-31
[ [ "Navarra", "F. S.", "" ], [ "Nielsen", "M.", "" ], [ "Bracco", "M. E.", "" ], [ "Chiapparini", "M.", "" ], [ "Schat", "C. L.", "" ] ]
The $H^*H\pi$ form factor for H = B and D mesons is evaluated in a QCD sum rule calculation. We study the Borel sum rule for the three point function of two pseudoscalar and one vector meson currents up to order four in the operator product expansion. The double Borel transform is performed with respect to the heavy meson momenta. We discuss the momentum dependence of the form factors and two different approaches to extract the $H^*H\pi$ coupling constant.
1906.05940
Alessandro Papa
Andr\`ee Dafne Bolognino, Francesco Giovanni Celiberto, Michael Fucilla, Dmitry Yu. Ivanov, Beatrice Murdaca, Alessandro Papa
Inclusive production of two rapidity-separated heavy quarks as a probe of BFKL dynamics
6 pages, 2 figures, 2 tables; contribution to the proceedings of the XXVII International Workshop on Deep Inelastic Scattering and Related Subjects (DIS2019), Torino, Italy, 8-12 April, 2019; to appear on Proceedings of Science
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The inclusive photoproduction of two heavy quarks, separated by a large rapidity interval, is proposed as a new channel for the manifestation of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. The extension to the hadroproduction case is also discussed.
[ { "created": "Thu, 13 Jun 2019 21:42:47 GMT", "version": "v1" } ]
2019-06-17
[ [ "Bolognino", "Andrèe Dafne", "" ], [ "Celiberto", "Francesco Giovanni", "" ], [ "Fucilla", "Michael", "" ], [ "Ivanov", "Dmitry Yu.", "" ], [ "Murdaca", "Beatrice", "" ], [ "Papa", "Alessandro", "" ] ]
The inclusive photoproduction of two heavy quarks, separated by a large rapidity interval, is proposed as a new channel for the manifestation of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) dynamics. The extension to the hadroproduction case is also discussed.
1010.5323
Eugene Levin
E. Gotsman, E. Levin and U. Maor
N=4 SYM and QCD motivated approach to soft interactions at high energies
36 pp. 20 figures and 3 tables
Eur.Phys.J.C71:1553,2011
10.1140/epjc/s10052-011-1553-1
TAUP-2924-10
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we construct a model that satisfies the theoretical requisites of high energy soft interactions, based on two ingredients:(i) the results of N=4 SYM, which at present is a unique theory that allows one to deal with a large coupling constant; and (ii) the requirement of matching with high energy QCD. In accordance with these ideas, we assume that the soft Pomeron intercept is rather large, and the slope of the Pomeron trajectory is equal to zero. We derive analytical formulae that sum both enhanced and semi-enhanced diagrams for elastic and diffractive amplitudes. We fit the available experimental data, and predict the valuefor cross sections at the energies accessible at the LHC. The main corrections to the model are studied and evaluated.
[ { "created": "Tue, 26 Oct 2010 07:20:31 GMT", "version": "v1" } ]
2011-03-10
[ [ "Gotsman", "E.", "" ], [ "Levin", "E.", "" ], [ "Maor", "U.", "" ] ]
In this paper we construct a model that satisfies the theoretical requisites of high energy soft interactions, based on two ingredients:(i) the results of N=4 SYM, which at present is a unique theory that allows one to deal with a large coupling constant; and (ii) the requirement of matching with high energy QCD. In accordance with these ideas, we assume that the soft Pomeron intercept is rather large, and the slope of the Pomeron trajectory is equal to zero. We derive analytical formulae that sum both enhanced and semi-enhanced diagrams for elastic and diffractive amplitudes. We fit the available experimental data, and predict the valuefor cross sections at the energies accessible at the LHC. The main corrections to the model are studied and evaluated.
2010.04960
Fabien Besnard
Fabien Besnard and Christian Brouder
Noncommutative geometry, the Lorentzian Standard Model and its B-L extension
Section VII.D has been entirely rewritten. A new section (VII.E) briefly discusses the 2-loop corrections
Phys. Rev. D 103, 035003 (2021)
10.1103/PhysRevD.103.035003
null
hep-ph hep-th math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the 1-loop renormalization group flow of two models coming from a generalization of the Connes-Lott version of Noncommutative Geometry in Lorentzian signature: the Noncommutative Standard Model and its B-L extension. Both make predictions on coupling constants at high energy, but only the latter is found to be compatible with the top quark and Higgs boson masses at the electroweak scale. We took into account corrections introduced by threshold effects and the relative positions of the Dirac and Majorana neutrino mass matrices and found them to be important. Some effects of 2-loop corrections are briefly discussed. The model is consistent with experiments only for a very small part of its parameter space and is thus predictive. The masses of the $Z'$ and B-L breaking scalar are found to be of the order $10^{14}$ GeV.
[ { "created": "Sat, 10 Oct 2020 09:44:46 GMT", "version": "v1" }, { "created": "Thu, 15 Oct 2020 08:03:59 GMT", "version": "v2" }, { "created": "Sat, 24 Oct 2020 11:55:16 GMT", "version": "v3" } ]
2021-02-10
[ [ "Besnard", "Fabien", "" ], [ "Brouder", "Christian", "" ] ]
We explore the 1-loop renormalization group flow of two models coming from a generalization of the Connes-Lott version of Noncommutative Geometry in Lorentzian signature: the Noncommutative Standard Model and its B-L extension. Both make predictions on coupling constants at high energy, but only the latter is found to be compatible with the top quark and Higgs boson masses at the electroweak scale. We took into account corrections introduced by threshold effects and the relative positions of the Dirac and Majorana neutrino mass matrices and found them to be important. Some effects of 2-loop corrections are briefly discussed. The model is consistent with experiments only for a very small part of its parameter space and is thus predictive. The masses of the $Z'$ and B-L breaking scalar are found to be of the order $10^{14}$ GeV.
hep-ph/9807465
Guido Montagna
G. Montagna, M. Moretti, O. Nicrosini and F. Piccinini
Single- and multi-photon final states with missing energy at e+e- colliders
LaTeX, 20 pages, 10 figures included
Nucl.Phys. B541 (1999) 31-49
10.1016/S0550-3213(98)00795-0
CERN/TH 98-238, FNT/T 98/07
hep-ph hep-ex
null
The search for new physics in single- and multi-photon final states with large missing energy at LEP and future e^+ e^- colliders requires precise predictions for the Standard Model irreducible background. While at LEP1 the theoretical situation is under control, going to LEP2 (and beyond) some improvements are necessary. To approach the aimed $O(1%)$ theoretical accuracy, the tree-level matrix elements for the processes $e^+ e^- \to \nu \bar\nu n\gamma$, with n=1,2,3, are exactly computed in the Standard Model, including the possibility of anomalous couplings for single-photon production. Due to the presence of observed photons in the final state, particular attention is paid to the treatment of higher-order QED corrections. Comparisons with existing calculations are shown and commented. An improved version of the event generator NUNUGPV is presented.
[ { "created": "Wed, 22 Jul 1998 14:20:56 GMT", "version": "v1" } ]
2009-10-31
[ [ "Montagna", "G.", "" ], [ "Moretti", "M.", "" ], [ "Nicrosini", "O.", "" ], [ "Piccinini", "F.", "" ] ]
The search for new physics in single- and multi-photon final states with large missing energy at LEP and future e^+ e^- colliders requires precise predictions for the Standard Model irreducible background. While at LEP1 the theoretical situation is under control, going to LEP2 (and beyond) some improvements are necessary. To approach the aimed $O(1%)$ theoretical accuracy, the tree-level matrix elements for the processes $e^+ e^- \to \nu \bar\nu n\gamma$, with n=1,2,3, are exactly computed in the Standard Model, including the possibility of anomalous couplings for single-photon production. Due to the presence of observed photons in the final state, particular attention is paid to the treatment of higher-order QED corrections. Comparisons with existing calculations are shown and commented. An improved version of the event generator NUNUGPV is presented.
1401.7351
D. Hudson Smith
Eric Braaten, Christian Langmack, D. Hudson Smith
Selection Rules for Hadronic Transitions of XYZ Mesons
5 pages
Phys. Rev. Lett. 112, 222001 (2014)
10.1103/PhysRevLett.112.222001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Many of the XYZ mesons discovered in the last decade can be identified as bound states of a heavy quark and antiquark in Born-Oppenheimer (B-O) potentials defined by the energy of gluon and light-quark fields in the presence of static color sources. The mesons include quarkonium hybrids, which are bound states in excited flavor-singlet B-O potentials, and quarkonium tetraquarks, which are bound states in flavor-nonsinglet B-O potentials. The deepest hybrid potentials are known from lattice QCD calculations. The deepest tetraquark potentials can be inferred from lattice QCD calculations of static adjoint mesons. Selection rules for hadronic transitions are derived and used to identify XYZ mesons that are candidates for ground-state energy levels in the B-O potentials for charmonium hybrids and tetraquarks.
[ { "created": "Tue, 28 Jan 2014 21:55:04 GMT", "version": "v1" }, { "created": "Thu, 30 Jan 2014 16:08:13 GMT", "version": "v2" } ]
2014-06-11
[ [ "Braaten", "Eric", "" ], [ "Langmack", "Christian", "" ], [ "Smith", "D. Hudson", "" ] ]
Many of the XYZ mesons discovered in the last decade can be identified as bound states of a heavy quark and antiquark in Born-Oppenheimer (B-O) potentials defined by the energy of gluon and light-quark fields in the presence of static color sources. The mesons include quarkonium hybrids, which are bound states in excited flavor-singlet B-O potentials, and quarkonium tetraquarks, which are bound states in flavor-nonsinglet B-O potentials. The deepest hybrid potentials are known from lattice QCD calculations. The deepest tetraquark potentials can be inferred from lattice QCD calculations of static adjoint mesons. Selection rules for hadronic transitions are derived and used to identify XYZ mesons that are candidates for ground-state energy levels in the B-O potentials for charmonium hybrids and tetraquarks.
1501.02991
Xun-Jie Xu
Werner Rodejohann, Xun-Jie Xu
Origin of Symmetric PMNS and CKM Matrices
8 pages. 4 figures. minor corrections to appear in PRD
Phys. Rev. D 91, 056004 (2015)
10.1103/PhysRevD.91.056004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The PMNS and CKM matrices are phenomenologically close to symmetric, and a symmetric form could be used as zeroth-order approximation for both matrices. We study the possible theoretical origin of this feature in flavor symmetry models. We identify necessary geometric properties of discrete flavor symmetry groups that can lead to symmetric mixing matrices. Those properties are actually very common in discrete groups such as $A_{4}$, $S_{4}$ or $\Delta(96)$. As an application of our theorem, we generate a symmetric lepton mixing scheme with $\theta_{12}=\theta_{23}=36.21^{\circ};\theta_{13}=12.20^{\circ}$ and $\delta=0$, realized with the group $\Delta(96)$.
[ { "created": "Tue, 13 Jan 2015 13:17:04 GMT", "version": "v1" }, { "created": "Mon, 19 Jan 2015 11:24:57 GMT", "version": "v2" }, { "created": "Sun, 22 Feb 2015 15:44:41 GMT", "version": "v3" } ]
2015-03-11
[ [ "Rodejohann", "Werner", "" ], [ "Xu", "Xun-Jie", "" ] ]
The PMNS and CKM matrices are phenomenologically close to symmetric, and a symmetric form could be used as zeroth-order approximation for both matrices. We study the possible theoretical origin of this feature in flavor symmetry models. We identify necessary geometric properties of discrete flavor symmetry groups that can lead to symmetric mixing matrices. Those properties are actually very common in discrete groups such as $A_{4}$, $S_{4}$ or $\Delta(96)$. As an application of our theorem, we generate a symmetric lepton mixing scheme with $\theta_{12}=\theta_{23}=36.21^{\circ};\theta_{13}=12.20^{\circ}$ and $\delta=0$, realized with the group $\Delta(96)$.
2212.07243
Ali N. Khorramian
Majid Azizi, Ali Khorramian, Saeid Paktinat Mehdiabadi
Parton distribution functions and QCD coupling constant from LHC and non-LHC data
29 pages, 14 figures, 5 tables
Phys. Rev. D 106 (2022) 11, 114042
10.1103/PhysRevD.106.114042
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We present a new QCD analysis of parton distribution functions (PDFs) at the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). In the present paper, the role of special types of experimental measurements for extracting PDFs is investigated and simultaneously the values of the strong coupling constant are determined. Essential elements of this QCD analysis are: the HERA combined data as a base, heavy quark cross section measurement together with Tevatron data on jet production and H1 and ZEUS jet cross sections as "non-LHC" data, and especially the "LHC" data set for top-quark and jet cross sections. These different data sets have allowed detailed information at low $x$, worth information on the nucleon's flavor and have played an important role for some PDFs at large-$x$ and strong coupling constant. Since the large-$x$ gluon PDF benefits from an accurate determination of quark PDFs, we have enough motivation to focus on the top-quark production and jet cross section measurements from LHC to find the impact of these data on the gluon PDF and strong coupling constant. These experimental data have an impact on the relative uncertainties of PDF. The gluon PDF at large-$x$ and the values of $\alpha_s(M_Z^2)$ are affected significantly. Although, the main motivation of this paper is to focus on gluon PDF and also its uncertainty at large-$x$, but notice to heavy PDFs behavior in this region is also very important. We study the intrinsic charm (IC) using BHPS model with together our extracted extrinsic charm PDF at large $x$ which can be very worth for future experiment at the LHC.
[ { "created": "Wed, 14 Dec 2022 14:25:08 GMT", "version": "v1" } ]
2024-05-20
[ [ "Azizi", "Majid", "" ], [ "Khorramian", "Ali", "" ], [ "Mehdiabadi", "Saeid Paktinat", "" ] ]
We present a new QCD analysis of parton distribution functions (PDFs) at the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). In the present paper, the role of special types of experimental measurements for extracting PDFs is investigated and simultaneously the values of the strong coupling constant are determined. Essential elements of this QCD analysis are: the HERA combined data as a base, heavy quark cross section measurement together with Tevatron data on jet production and H1 and ZEUS jet cross sections as "non-LHC" data, and especially the "LHC" data set for top-quark and jet cross sections. These different data sets have allowed detailed information at low $x$, worth information on the nucleon's flavor and have played an important role for some PDFs at large-$x$ and strong coupling constant. Since the large-$x$ gluon PDF benefits from an accurate determination of quark PDFs, we have enough motivation to focus on the top-quark production and jet cross section measurements from LHC to find the impact of these data on the gluon PDF and strong coupling constant. These experimental data have an impact on the relative uncertainties of PDF. The gluon PDF at large-$x$ and the values of $\alpha_s(M_Z^2)$ are affected significantly. Although, the main motivation of this paper is to focus on gluon PDF and also its uncertainty at large-$x$, but notice to heavy PDFs behavior in this region is also very important. We study the intrinsic charm (IC) using BHPS model with together our extracted extrinsic charm PDF at large $x$ which can be very worth for future experiment at the LHC.
2110.01789
Terry Mart
N. H. Luthfiyah and T. Mart
Role of the high-spin nucleon and delta resonances in the $K\Lambda$ and $K\Sigma$ photoproduction off the nucleon
26 pages, 21 figures
Phys. Rev. D 104, 076022 (2021)
10.1103/PhysRevD.104.076022
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We have investigated the effect of nucleon and delta resonances with spins 11/2, 13/2, and 15/2 in the kaon photoproduction process $\gamma + N \to K + Y$ by using two covariant isobar models. The formalism for high-spin propagators and interaction Lagrangians were adopted from the works of Pascalutsa and Vrancx et al. The unknown parameters in the amplitudes, i.e., the coupling constants and hadronic form factor cutoffs, were obtained by fitting the calculated observables to experimental data. In the $K\Lambda$ channels the inclusion of $N(2600)I_{1,11}$ and $N(2700)K_{1,13}$ resonances improves the agreement between model calculations and experimental data significantly and reduces the dominance of resonances in the model by increasing the hadronic form factor cutoff of the Born terms. Furthermore, the inclusion of these resonances reduces the number of resonance structures in cross sections, including the structure in the $K^0\Lambda$ differential cross section at $W\approx 1650$ MeV, which could become a hint of the narrow resonance. In the $K\Sigma$ channels the inclusion of $N(2600)I_{1,11}$, $N(2700)K_{1,13}$, $\Delta(2420)H_{3,11}$, $\Delta(2750)I_{3,13}$, and $\Delta(2950)K_{3,15}$ states also significantly improves the model and increases the hadronic form factor cutoff of the Born terms. However, different from the $K\Lambda$ channels, the inclusion of these high-spin resonances leads to more resonance structures in the $K^+\Sigma^0$ differential cross section. This investigation reveals that the second and third peaks in the $K^+\Sigma^0$ differential cross section originate from the $\Delta(2000)F_{35}$ and $N(2290)G_{19}$ resonances, respectively. We have also evaluated the resonance properties at the pole positions and using the Breit-Wigner method.
[ { "created": "Tue, 5 Oct 2021 02:22:54 GMT", "version": "v1" } ]
2021-10-25
[ [ "Luthfiyah", "N. H.", "" ], [ "Mart", "T.", "" ] ]
We have investigated the effect of nucleon and delta resonances with spins 11/2, 13/2, and 15/2 in the kaon photoproduction process $\gamma + N \to K + Y$ by using two covariant isobar models. The formalism for high-spin propagators and interaction Lagrangians were adopted from the works of Pascalutsa and Vrancx et al. The unknown parameters in the amplitudes, i.e., the coupling constants and hadronic form factor cutoffs, were obtained by fitting the calculated observables to experimental data. In the $K\Lambda$ channels the inclusion of $N(2600)I_{1,11}$ and $N(2700)K_{1,13}$ resonances improves the agreement between model calculations and experimental data significantly and reduces the dominance of resonances in the model by increasing the hadronic form factor cutoff of the Born terms. Furthermore, the inclusion of these resonances reduces the number of resonance structures in cross sections, including the structure in the $K^0\Lambda$ differential cross section at $W\approx 1650$ MeV, which could become a hint of the narrow resonance. In the $K\Sigma$ channels the inclusion of $N(2600)I_{1,11}$, $N(2700)K_{1,13}$, $\Delta(2420)H_{3,11}$, $\Delta(2750)I_{3,13}$, and $\Delta(2950)K_{3,15}$ states also significantly improves the model and increases the hadronic form factor cutoff of the Born terms. However, different from the $K\Lambda$ channels, the inclusion of these high-spin resonances leads to more resonance structures in the $K^+\Sigma^0$ differential cross section. This investigation reveals that the second and third peaks in the $K^+\Sigma^0$ differential cross section originate from the $\Delta(2000)F_{35}$ and $N(2290)G_{19}$ resonances, respectively. We have also evaluated the resonance properties at the pole positions and using the Breit-Wigner method.
hep-ph/0511047
Markus Diehl
M. Arneodo and M. Diehl
Diffraction for non-believers
23 pages, 26 figures. Contributed to the Proceedings of the Workshop on HERA and the LHC, DESY and CERN, 2004-2005
null
null
DESY-05-214
hep-ph hep-ex
null
Diffractive reactions involving a hard scale can be understood in terms of quarks and gluons. These reactions have become a valuable tool for investigating the low-x structure of the proton and the behavior of QCD in the high-density regime, and they may provide a clean environment to study or even discover the Higgs boson at the LHC. In this paper we give a brief introduction to the description of diffraction in QCD. We focus on key features studied in ep collisions at HERA and outline challenges for understanding diffractive interactions at the LHC.
[ { "created": "Fri, 4 Nov 2005 14:53:55 GMT", "version": "v1" } ]
2007-05-23
[ [ "Arneodo", "M.", "" ], [ "Diehl", "M.", "" ] ]
Diffractive reactions involving a hard scale can be understood in terms of quarks and gluons. These reactions have become a valuable tool for investigating the low-x structure of the proton and the behavior of QCD in the high-density regime, and they may provide a clean environment to study or even discover the Higgs boson at the LHC. In this paper we give a brief introduction to the description of diffraction in QCD. We focus on key features studied in ep collisions at HERA and outline challenges for understanding diffractive interactions at the LHC.
hep-ph/0010039
null
Tetsuo Hatsuda (Univ. of Tokyo) and Teiji Kunihiro (Yukawa Institute for Theoretical Physics, Kyoto Univ.)
Chiral Symmetry Restoration and the sigma-meson
7 pages, 3 figures, Invited talk at the International Workshop on ``Possible Existence of the Light $\sigma$ Resonance and its Implication to Hadron Physics'', (June 11-14, 2000, Yukawa Institute for Theoretical Physics, Kyoto, Japan)
null
null
null
hep-ph nucl-th
null
The sigma-meson, which is at best a broad resonance in the vacuum, may suffer a substantial red-shift and appear as a soft and narrow collective mode at finite temperature and baryon densities. The physics behind this softening phenomena and its relation to the partial restoration of chiral symmetry are discussed. Possible experiments in laboratory to test the idea are also summarized.
[ { "created": "Thu, 5 Oct 2000 08:25:48 GMT", "version": "v1" } ]
2007-05-23
[ [ "Hatsuda", "Tetsuo", "", "Univ. of Tokyo" ], [ "Kunihiro", "Teiji", "", "Yukawa Institute\n for Theoretical Physics, Kyoto Univ." ] ]
The sigma-meson, which is at best a broad resonance in the vacuum, may suffer a substantial red-shift and appear as a soft and narrow collective mode at finite temperature and baryon densities. The physics behind this softening phenomena and its relation to the partial restoration of chiral symmetry are discussed. Possible experiments in laboratory to test the idea are also summarized.
0810.2798
Bruno Mintz
B. W. Mintz, A. Bessa, E. S. Fraga
On the nucleation of hadronic domains in the quark-hadron transition
4 pages, 2 images. To be published in the proceedings of SEWM 2008
null
10.1016/j.nuclphysa.2009.01.072
null
hep-ph astro-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present numerical results on bubble profiles, nucleation rates and time evolution for a weakly first-order quark-hadron phase transition in different expansion scenarios. We confirm the standard picture of a cosmological first-order phase transition, in which the phase transition is entirely dominated by nucleation. We also show that, even for expansion rates much lower than those expected in heavy-ion collisions nucleation is very unlikely, indicating that the main phase conversion mechanism is spinodal decomposition.
[ { "created": "Wed, 15 Oct 2008 20:17:47 GMT", "version": "v1" } ]
2009-11-13
[ [ "Mintz", "B. W.", "" ], [ "Bessa", "A.", "" ], [ "Fraga", "E. S.", "" ] ]
We present numerical results on bubble profiles, nucleation rates and time evolution for a weakly first-order quark-hadron phase transition in different expansion scenarios. We confirm the standard picture of a cosmological first-order phase transition, in which the phase transition is entirely dominated by nucleation. We also show that, even for expansion rates much lower than those expected in heavy-ion collisions nucleation is very unlikely, indicating that the main phase conversion mechanism is spinodal decomposition.
2202.04874
Pralay Chakraborty
Pralay Chakraborty, Manash Dey, Subhankar Roy
Constrained Neutrino Mass Matrix and Majorana Phases
null
Journal of Physics G: Nuclear and Particle Physics, 51, (2023), 015003
10.1088/1361-6471/ad074c
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We endeavor to constrain the neutrino mass matrix on the phenomenological ground and procure model-independent textures by emphasizing on the simple linear relationships among the mass matrix elements. These simple textures predict the two Majorana phases. In this regard, two types of parametrization of neutrino mass matrix: general and exponential are employed. We obtain fifty-three predictive neutrino mass matrix textures, out of which twenty-eight are associated with the general parametrization, and the rest belong to the exponential one. Apart from Type-A/P textures, the rest deal with the prediction of a few other oscillation parameters as well. We try to realize the proposed textures in the light of $A_4$, $\Delta\,(27)$ and $T_7$ symmetry groups.
[ { "created": "Thu, 10 Feb 2022 07:19:26 GMT", "version": "v1" }, { "created": "Tue, 24 May 2022 07:58:59 GMT", "version": "v2" }, { "created": "Wed, 28 Dec 2022 14:47:04 GMT", "version": "v3" }, { "created": "Thu, 7 Dec 2023 18:13:22 GMT", "version": "v4" } ]
2024-01-29
[ [ "Chakraborty", "Pralay", "" ], [ "Dey", "Manash", "" ], [ "Roy", "Subhankar", "" ] ]
We endeavor to constrain the neutrino mass matrix on the phenomenological ground and procure model-independent textures by emphasizing on the simple linear relationships among the mass matrix elements. These simple textures predict the two Majorana phases. In this regard, two types of parametrization of neutrino mass matrix: general and exponential are employed. We obtain fifty-three predictive neutrino mass matrix textures, out of which twenty-eight are associated with the general parametrization, and the rest belong to the exponential one. Apart from Type-A/P textures, the rest deal with the prediction of a few other oscillation parameters as well. We try to realize the proposed textures in the light of $A_4$, $\Delta\,(27)$ and $T_7$ symmetry groups.
1811.07571
Shih-Yen Tseng
Kento Asai, Koichi Hamaguchi, Natsumi Nagata, Shih-Yen Tseng, Koji Tsumura
Minimal Gauged U(1)$_{L_\alpha - L_\beta}$ Models Driven into a Corner
25 pages, 7 figures
Phys. Rev. D 99, 055029 (2019)
10.1103/PhysRevD.99.055029
UT-18-28, IPMU18-0191, KUNS-2740
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is well known that the differences between the lepton numbers can be gauged with the Standard Model matter content. Such extended gauge theories, dubbed as the gauged U(1)$_{L_\alpha - L_\beta}$ models, have been widely discussed so far as potential candidates for physics beyond the Standard Model. In this work, we study the minimal versions of these gauge theories, where three right-handed neutrinos as well as a single U(1)$_{L_\alpha - L_\beta}$ symmetry breaking Higgs field---an SU(2)$_L$ singlet or doublet---are introduced. In these minimal models, the neutrino mass terms are constrained by the gauge symmetry, which result in the two-zero texture or two-zero minor structure of neutrino mass matrices. Such restrictive forms of neutrino mass matrices lead to non-trivial predictions for the neutrino oscillation parameters as well as the size of the mass eigenvalues. We find that due to this restriction the minimal gauged U(1)$_{L_\alpha - L_\beta}$ models are either incompatible with the observed values of the neutrino parameters or in strong tension with the Planck 2018 limit on the sum of the neutrino masses. Only the U(1)$_{L_\mu-L_\tau}$ model with an SU(2)$_L$ singlet U(1)$_{L_\mu-L_\tau}$-breaking field barely evades the limit, which can be tested in the future neutrino experiments.
[ { "created": "Mon, 19 Nov 2018 09:39:45 GMT", "version": "v1" }, { "created": "Thu, 28 Mar 2019 12:55:29 GMT", "version": "v2" } ]
2019-03-29
[ [ "Asai", "Kento", "" ], [ "Hamaguchi", "Koichi", "" ], [ "Nagata", "Natsumi", "" ], [ "Tseng", "Shih-Yen", "" ], [ "Tsumura", "Koji", "" ] ]
It is well known that the differences between the lepton numbers can be gauged with the Standard Model matter content. Such extended gauge theories, dubbed as the gauged U(1)$_{L_\alpha - L_\beta}$ models, have been widely discussed so far as potential candidates for physics beyond the Standard Model. In this work, we study the minimal versions of these gauge theories, where three right-handed neutrinos as well as a single U(1)$_{L_\alpha - L_\beta}$ symmetry breaking Higgs field---an SU(2)$_L$ singlet or doublet---are introduced. In these minimal models, the neutrino mass terms are constrained by the gauge symmetry, which result in the two-zero texture or two-zero minor structure of neutrino mass matrices. Such restrictive forms of neutrino mass matrices lead to non-trivial predictions for the neutrino oscillation parameters as well as the size of the mass eigenvalues. We find that due to this restriction the minimal gauged U(1)$_{L_\alpha - L_\beta}$ models are either incompatible with the observed values of the neutrino parameters or in strong tension with the Planck 2018 limit on the sum of the neutrino masses. Only the U(1)$_{L_\mu-L_\tau}$ model with an SU(2)$_L$ singlet U(1)$_{L_\mu-L_\tau}$-breaking field barely evades the limit, which can be tested in the future neutrino experiments.
hep-ph/0212154
Jeff Forshaw
J R Forshaw
Selected Topics in Rapidity Gap Physics
14 pages. Talk presented at HCP2002, Karlsruhe
null
null
MC-TH-2002/13
hep-ph
null
This talk will review selected topics in rapidity gap physics. In particular I will discuss diffractive jet production and the possibility of searching for the higgs boson using diffraction at the LHC; the dipole picture of diffraction and saturation; and those processes where a large momentum is transferred across the rapidity gap, for which there has been recent progress both experimentally and theoretically.
[ { "created": "Wed, 11 Dec 2002 11:43:17 GMT", "version": "v1" } ]
2007-05-23
[ [ "Forshaw", "J R", "" ] ]
This talk will review selected topics in rapidity gap physics. In particular I will discuss diffractive jet production and the possibility of searching for the higgs boson using diffraction at the LHC; the dipole picture of diffraction and saturation; and those processes where a large momentum is transferred across the rapidity gap, for which there has been recent progress both experimentally and theoretically.
0712.0885
Georgii Shestakov
N.N. Achasov, G.N. Shestakov
Lightest scalar and tensor resonances in $\gamma\gamma\to\pi\pi$ after the Belle experiment
14 pages, 5 figures. Fitted for the publication in Physical Review D
Phys.Rev.D77:074020,2008
10.1103/PhysRevD.77.074020
null
hep-ph hep-ex nucl-th
null
New high statistics Belle data on the $\gamma\gamma\to\pi^+\pi^-$ reaction cross section measured in the range of pion-pair invariant masses $\sqrt{s}$ between 0.8 GeV and 1.5 GeV are analyzed to clarify the current situation around the $\sigma(600)$, $f_0(980)$, and $f_2(1270)$ resonances in $\gamma\gamma$ collisions. The present analysis shows that the direct coupling constants of the $\sigma(600)$ and $f_0(980)$ resonances to $\gamma\gamma$ are small, and the $\sigma(600)\to\gamma\gamma$ and $f_0(980)\to\gamma\gamma$ decays are four-quark transitions caused by the $\pi^+\pi^-$ and $K^+K^-$ loop mechanisms, respectively. The chiral shielding of the $\sigma(600)$ resonance takes place in the reactions $\gamma\gamma\to\pi\pi$ as well as in $\pi\pi$ scattering. Some results of a simultaneous description of the $\gamma\gamma\to\pi^+\pi^-$ and $\gamma\gamma\to\pi^0\pi^0$ Belle data are also presented. In particular, the following tentative estimate of the $f_2(1270)\to\gamma\gamma$ decay width is obtained: $\Gamma_{f_2\to\gamma\gamma}(m^2_{f_2})\approx 3.68$ keV.
[ { "created": "Thu, 6 Dec 2007 12:34:08 GMT", "version": "v1" }, { "created": "Wed, 26 Mar 2008 06:27:16 GMT", "version": "v2" }, { "created": "Mon, 28 Apr 2008 06:39:43 GMT", "version": "v3" } ]
2008-11-26
[ [ "Achasov", "N. N.", "" ], [ "Shestakov", "G. N.", "" ] ]
New high statistics Belle data on the $\gamma\gamma\to\pi^+\pi^-$ reaction cross section measured in the range of pion-pair invariant masses $\sqrt{s}$ between 0.8 GeV and 1.5 GeV are analyzed to clarify the current situation around the $\sigma(600)$, $f_0(980)$, and $f_2(1270)$ resonances in $\gamma\gamma$ collisions. The present analysis shows that the direct coupling constants of the $\sigma(600)$ and $f_0(980)$ resonances to $\gamma\gamma$ are small, and the $\sigma(600)\to\gamma\gamma$ and $f_0(980)\to\gamma\gamma$ decays are four-quark transitions caused by the $\pi^+\pi^-$ and $K^+K^-$ loop mechanisms, respectively. The chiral shielding of the $\sigma(600)$ resonance takes place in the reactions $\gamma\gamma\to\pi\pi$ as well as in $\pi\pi$ scattering. Some results of a simultaneous description of the $\gamma\gamma\to\pi^+\pi^-$ and $\gamma\gamma\to\pi^0\pi^0$ Belle data are also presented. In particular, the following tentative estimate of the $f_2(1270)\to\gamma\gamma$ decay width is obtained: $\Gamma_{f_2\to\gamma\gamma}(m^2_{f_2})\approx 3.68$ keV.
1202.5190
Saurabh Niyogi
Nishita Desai, Biswarup Mukhopadhyaya, Saurabh Niyogi
Constraints on invisible Higgs decay in MSSM in the light of diphoton rates from the LHC
11 pages, 4 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the parameter space of the purely phenomenological minimal super- symmetric standard model (MSSM), without assuming any supersymmetry breaking scheme. We find that a large region of the parameter space can indeed yield the lightest neutral Higgs mass around 125 GeV, as suggested by the recent ATLAS data, and also lead to event rates around, or slightly higher than, the standard model expectation in the two-photon and four-lepton channels. Using a lightest neutralino that is considerably lighter than the Higgs, we find that the 'invisible' decay of the Higgs into a pair of neutralinos upto about 10% can be consistent with the current data from the Large Hadron Collider (LHC).
[ { "created": "Thu, 23 Feb 2012 14:23:25 GMT", "version": "v1" } ]
2012-02-29
[ [ "Desai", "Nishita", "" ], [ "Mukhopadhyaya", "Biswarup", "" ], [ "Niyogi", "Saurabh", "" ] ]
We examine the parameter space of the purely phenomenological minimal super- symmetric standard model (MSSM), without assuming any supersymmetry breaking scheme. We find that a large region of the parameter space can indeed yield the lightest neutral Higgs mass around 125 GeV, as suggested by the recent ATLAS data, and also lead to event rates around, or slightly higher than, the standard model expectation in the two-photon and four-lepton channels. Using a lightest neutralino that is considerably lighter than the Higgs, we find that the 'invisible' decay of the Higgs into a pair of neutralinos upto about 10% can be consistent with the current data from the Large Hadron Collider (LHC).
hep-ph/0407006
Gursevil Turan
U. O. Yilmaz, B. B. Sirvanli and G. Turan
A General analysis of the lepton polarizations in Bs ->\gamma \ell^+ \ell^- decays
21 pages, 12 figures
Nucl.Phys. B692 (2004) 249
10.1016/j.nuclphysb.2004.05.026
null
hep-ph
null
We present a general analysis of the lepton polarizations in the rare Bs ->\gamma \ell^+ \ell^- decays by using the most general model independent form of the effective Hamiltonian. The sensitivity of the longitudinal, transverse and normal polarizations of final state leptons, as well as lepton-antilepton combined asymmetries, on the new Wilson coefficients are investigated. It has been shown that all these physical observables are very sensitive to the existence of new physics beyond the standard model and their experimental measurements can give valuable information about it.
[ { "created": "Thu, 1 Jul 2004 07:41:17 GMT", "version": "v1" } ]
2009-11-10
[ [ "Yilmaz", "U. O.", "" ], [ "Sirvanli", "B. B.", "" ], [ "Turan", "G.", "" ] ]
We present a general analysis of the lepton polarizations in the rare Bs ->\gamma \ell^+ \ell^- decays by using the most general model independent form of the effective Hamiltonian. The sensitivity of the longitudinal, transverse and normal polarizations of final state leptons, as well as lepton-antilepton combined asymmetries, on the new Wilson coefficients are investigated. It has been shown that all these physical observables are very sensitive to the existence of new physics beyond the standard model and their experimental measurements can give valuable information about it.
hep-ph/0303022
Vadim Guzey
L. Frankfurt (Tel Aviv U.), V. Guzey (Ruhr U., Bochum), M. Strikman (Penn State U.)
Leading twist nuclear shadowing: uncertainties, comparison to experiments and higher twist effects
42 pages, 18 figures, 1 table, RevTex. The final version published in PRD 71, 054001 (2005)
Phys.Rev.D71:054001,2005
10.1103/PhysRevD.71.054001
RUB-TP2-03/03
hep-ph
null
Using the leading twist approach to nuclear shadowing, which is based on the relationship between nuclear shadowing and diffraction on a nucleon, we calculate next-to-leading order nuclear parton distribution functions (nPDFs) and structure functions in the region $0.2 > x > 10^{-5}$ and $Q^2 \geq 4$ GeV$^2$. The uncertainties of our predictions due the uncertainties of the experimental input and the theory are quantified. We determine the relative role of the small ($\sim Q^2$) and large ($\gg Q^2$) diffractive masses in nuclear shadowing as a function of $x$ and find that the large mass contribution, which is an analog of the triple Pomeron exchange, becomes significant only for $x \le 10^{-4}$. Comparing our predictions to the available fixed-target nuclear DIS data, we argue, based on the current experimental studies of the leading twist diffraction, that the data at moderately small $x\sim 0.01$ and $Q^2 \sim 2$ GeV$^2$ could contain significant higher twist effects hindering the extraction of nPDFs from that data. Also, we find that the next-to-leading order effects in nuclear shadowing in the ratio of the nucleus to nucleon structure functions $F_2$ are quite sizable. Within the same formalism, we also present results for the impact parameter dependence of nPDFs. We also address the problem of extracting of the neutron $F_{2n}(x,Q^2)$ from the deuteron and proton data. We suggest a simple and nearly model-independent procedure of correcting for nuclear shadowing effects using $F_2^A/F_2^D$ ratios.
[ { "created": "Tue, 4 Mar 2003 16:54:11 GMT", "version": "v1" }, { "created": "Thu, 29 May 2003 08:33:49 GMT", "version": "v2" }, { "created": "Sun, 11 Jul 2004 21:40:04 GMT", "version": "v3" }, { "created": "Thu, 21 Apr 2005 09:16:26 GMT", "version": "v4" } ]
2011-07-19
[ [ "Frankfurt", "L.", "", "Tel Aviv U." ], [ "Guzey", "V.", "", "Ruhr U., Bochum" ], [ "Strikman", "M.", "", "Penn State U." ] ]
Using the leading twist approach to nuclear shadowing, which is based on the relationship between nuclear shadowing and diffraction on a nucleon, we calculate next-to-leading order nuclear parton distribution functions (nPDFs) and structure functions in the region $0.2 > x > 10^{-5}$ and $Q^2 \geq 4$ GeV$^2$. The uncertainties of our predictions due the uncertainties of the experimental input and the theory are quantified. We determine the relative role of the small ($\sim Q^2$) and large ($\gg Q^2$) diffractive masses in nuclear shadowing as a function of $x$ and find that the large mass contribution, which is an analog of the triple Pomeron exchange, becomes significant only for $x \le 10^{-4}$. Comparing our predictions to the available fixed-target nuclear DIS data, we argue, based on the current experimental studies of the leading twist diffraction, that the data at moderately small $x\sim 0.01$ and $Q^2 \sim 2$ GeV$^2$ could contain significant higher twist effects hindering the extraction of nPDFs from that data. Also, we find that the next-to-leading order effects in nuclear shadowing in the ratio of the nucleus to nucleon structure functions $F_2$ are quite sizable. Within the same formalism, we also present results for the impact parameter dependence of nPDFs. We also address the problem of extracting of the neutron $F_{2n}(x,Q^2)$ from the deuteron and proton data. We suggest a simple and nearly model-independent procedure of correcting for nuclear shadowing effects using $F_2^A/F_2^D$ ratios.
hep-ph/9608202
Svjetlana Fajfer, Ijs
S. Fajfer
The role of resonances in rare K decays
5 pages, Latex
null
null
IJS-TP-96/16
hep-ph
null
The decays $K \to \pi l^{+} l^{-}$, $K \to \pi \gamma \gamma $ and $K \to \pi \nu {\bar \nu}$ are investigated using the higher order terms of the chiral perturbation theory. The counterterms induced by strong, weak and electromagnetic interactions are determined assuming the resonance exchange. (Talk presented at the Workshop on K-Physics, Orsay, France, 30 May - 4 June, 1996)
[ { "created": "Thu, 1 Aug 1996 15:29:49 GMT", "version": "v1" } ]
2007-05-23
[ [ "Fajfer", "S.", "" ] ]
The decays $K \to \pi l^{+} l^{-}$, $K \to \pi \gamma \gamma $ and $K \to \pi \nu {\bar \nu}$ are investigated using the higher order terms of the chiral perturbation theory. The counterterms induced by strong, weak and electromagnetic interactions are determined assuming the resonance exchange. (Talk presented at the Workshop on K-Physics, Orsay, France, 30 May - 4 June, 1996)
hep-ph/9712323
Arkady Vainshtein
Arkady Vainshtein
HQET and Semileptonic Form Factors
10 pages, Latex
null
null
TPI-MINN-31-97, HEP-97-1617
hep-ph
null
(Contribution to Proceedings of the Seventh International Symposium On Heavy Flavor Physics, July 7-11, 1997, Santa Barbara.) Theoretical approaches to form factors of semileptonic decays are discussed in application to $B \ra D + l+\bar \nu_l$ decay.
[ { "created": "Wed, 10 Dec 1997 07:14:55 GMT", "version": "v1" } ]
2007-05-23
[ [ "Vainshtein", "Arkady", "" ] ]
(Contribution to Proceedings of the Seventh International Symposium On Heavy Flavor Physics, July 7-11, 1997, Santa Barbara.) Theoretical approaches to form factors of semileptonic decays are discussed in application to $B \ra D + l+\bar \nu_l$ decay.
1805.11094
Christoph Andreas Ternes
Gabriela Barenboim, Mehedi Masud, Christoph A. Ternes, Mariam T\'ortola
Exploring the intrinsic Lorentz-violating parameters at DUNE
13 pages, 7 figures, 2 tables, version 2, accepted for publication in Physics Letters B
null
10.1016/j.physletb.2018.11.040
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neutrinos can push our search for new physics to a whole new level. What makes them so hard to be detected, what allows them to travel humongous distances without being stopped or deflected allows to amplify Planck suppressed effects (or effects of comparable size) to the level we can measure or bound in DUNE. In this work we analyse the sensitivity of DUNE to CPT and Lorentz--violating interactions in a framework that allows a straightforward extrapolation of the bounds obtained to any phenomenological modification of the dispersion relation of neutrinos.
[ { "created": "Mon, 28 May 2018 18:00:00 GMT", "version": "v1" }, { "created": "Mon, 19 Nov 2018 16:31:16 GMT", "version": "v2" } ]
2018-11-28
[ [ "Barenboim", "Gabriela", "" ], [ "Masud", "Mehedi", "" ], [ "Ternes", "Christoph A.", "" ], [ "Tórtola", "Mariam", "" ] ]
Neutrinos can push our search for new physics to a whole new level. What makes them so hard to be detected, what allows them to travel humongous distances without being stopped or deflected allows to amplify Planck suppressed effects (or effects of comparable size) to the level we can measure or bound in DUNE. In this work we analyse the sensitivity of DUNE to CPT and Lorentz--violating interactions in a framework that allows a straightforward extrapolation of the bounds obtained to any phenomenological modification of the dispersion relation of neutrinos.
hep-ph/0508091
Werner Bernreuther
W. Bernreuther, M. Fuecker, Z. G. Si
Mixed QCD and weak corrections to top quark pair production at hadron colliders
12 pages, 9 figures
Phys.Lett. B633 (2006) 54-60
10.1016/j.physletb.2005.11.056
PITHA 05/03, SDU-HEP200502
hep-ph
null
The order $\alpha_s^2 \alpha$ mixed QCD and weak corrections to top quark pair production by quark antiquark annihilation are computed, keeping the full dependence on the $t$ and $\bar t$ spins. We determine the contributions to the cross section and to single and double top spin asymmetries at the parton level. These results are necessary ingredients for precise standard model predictions of top quark observables, in particular of top spin-induced parity-violating angular correlations and asymmetries at hadron colliders.
[ { "created": "Mon, 8 Aug 2005 08:13:34 GMT", "version": "v1" } ]
2009-11-11
[ [ "Bernreuther", "W.", "" ], [ "Fuecker", "M.", "" ], [ "Si", "Z. G.", "" ] ]
The order $\alpha_s^2 \alpha$ mixed QCD and weak corrections to top quark pair production by quark antiquark annihilation are computed, keeping the full dependence on the $t$ and $\bar t$ spins. We determine the contributions to the cross section and to single and double top spin asymmetries at the parton level. These results are necessary ingredients for precise standard model predictions of top quark observables, in particular of top spin-induced parity-violating angular correlations and asymmetries at hadron colliders.
1604.00509
Andrei Kataev
Gorazd Cveti\v{c} and A.L. Kataev
Adler function and Bjorken polarized sum rule: Perturbation expansions in powers of $SU(N_c)$ conformal anomaly and studies of the conformal symmetry limit
7 pages, Extra clarifications added, 1 reference added, prepared following the version accepted for publication to Phys.Rev.D Rapid Communications section
Phys. Rev. D 94, 014006 (2016)
10.1103/PhysRevD.94.014006
INR-TH-2016-003 , USM-TH-341
hep-ph hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a new form of analytical perturbation theory expansion in the massless $SU(N_c)$ theory, for the non-singlet part of the $e^+e^-$-annihilation to hadrons Adler function $D^{ns}$ and of the Bjorken sum rule of the polarized lepton-hadron deep-inelastic scattering $C_{ns}^{Bjp}$, and demonstrate its validity at the $O(\alpha_s^4)$-level at least. It is a two-fold series in terms of powers of the conformal anomaly and of $SU(N_c)$ coupling $\alpha_s$. Explicit expressions are obtained for the $\{\beta\}$-expanded perturbation coefficients at $O(\alpha_s^4)$ level in $\bar{\rm MS}$ scheme, for both considered physical quqantities. Comparisons of the terms in the $\{\beta\}$-expanded coefficients are made with the corresponding terms obtained by using extra gluino degrees of freedom, or skeleton-motivated expansion, or $R_{\delta}$-scheme motivated expansion in the Principle of Maximal Conformality. Relations between terms of the $\{\beta\}$-expansion for the $D^{ns}$- and $C_{ns}^{Bjp}$-functions, which follow from the conformal symmetry limit and its violation, are presnted. The relevance to the possible new analysis of the experimental data for the Adler function and Bjorken sum rule is discussed.
[ { "created": "Sat, 2 Apr 2016 14:39:14 GMT", "version": "v1" }, { "created": "Tue, 7 Jun 2016 16:46:48 GMT", "version": "v2" }, { "created": "Mon, 20 Jun 2016 12:46:53 GMT", "version": "v3" } ]
2016-07-13
[ [ "Cvetič", "Gorazd", "" ], [ "Kataev", "A. L.", "" ] ]
We consider a new form of analytical perturbation theory expansion in the massless $SU(N_c)$ theory, for the non-singlet part of the $e^+e^-$-annihilation to hadrons Adler function $D^{ns}$ and of the Bjorken sum rule of the polarized lepton-hadron deep-inelastic scattering $C_{ns}^{Bjp}$, and demonstrate its validity at the $O(\alpha_s^4)$-level at least. It is a two-fold series in terms of powers of the conformal anomaly and of $SU(N_c)$ coupling $\alpha_s$. Explicit expressions are obtained for the $\{\beta\}$-expanded perturbation coefficients at $O(\alpha_s^4)$ level in $\bar{\rm MS}$ scheme, for both considered physical quqantities. Comparisons of the terms in the $\{\beta\}$-expanded coefficients are made with the corresponding terms obtained by using extra gluino degrees of freedom, or skeleton-motivated expansion, or $R_{\delta}$-scheme motivated expansion in the Principle of Maximal Conformality. Relations between terms of the $\{\beta\}$-expansion for the $D^{ns}$- and $C_{ns}^{Bjp}$-functions, which follow from the conformal symmetry limit and its violation, are presnted. The relevance to the possible new analysis of the experimental data for the Adler function and Bjorken sum rule is discussed.
0804.3792
C.B. Jackson
C.B. Jackson
Dark Matter in the Private Higgs Model
16 pages, 4 figures. Revised model section. Removed Unitarity analysis. Major conclusions on Dark Matter analysis relatively unchanged
null
null
BNL-HET-08/10
hep-ph astro-ph
http://creativecommons.org/licenses/publicdomain/
The extremely large hierarchy observed in the fermion mass spectrum remains as one of the most puzzling and unresolved issues in particle physics. In a recent proposal, however, it was demonstrated that by introducing one Higgs doublet (or Private Higgs) per fermion this hierarchy could be made natural by making the Yukawa couplings between each fermion and its respective Higgs boson of order unity. Among the interesting predictions of the Private Higgs scenario is a variety of scalars which could be probed at future collider experiments and a possible dark matter candidate. In this paper, we study in some detail the dark matter sector of the Private Higgs model. We first calculate the annihilation cross sections of dark matter in this model and find that one can easily account for the observed density of dark matter in the Universe with relatively natural values of the model's parameters. Finally, we investigate the possibility of detecting Private Higgs dark matter indirectly via the observation of anomalous gamma rays originating from the galactic halo. We show that a substantial flux of photons can be produced from the annihilation of Private Higgs dark matter such that, if there is considerable clumping of dark matter in the galactic halo, the flux of these gamma rays could be observed by ground-based telescope arrays such as VERITAS and HESS.
[ { "created": "Wed, 23 Apr 2008 19:30:37 GMT", "version": "v1" }, { "created": "Tue, 27 May 2008 15:15:39 GMT", "version": "v2" } ]
2008-05-27
[ [ "Jackson", "C. B.", "" ] ]
The extremely large hierarchy observed in the fermion mass spectrum remains as one of the most puzzling and unresolved issues in particle physics. In a recent proposal, however, it was demonstrated that by introducing one Higgs doublet (or Private Higgs) per fermion this hierarchy could be made natural by making the Yukawa couplings between each fermion and its respective Higgs boson of order unity. Among the interesting predictions of the Private Higgs scenario is a variety of scalars which could be probed at future collider experiments and a possible dark matter candidate. In this paper, we study in some detail the dark matter sector of the Private Higgs model. We first calculate the annihilation cross sections of dark matter in this model and find that one can easily account for the observed density of dark matter in the Universe with relatively natural values of the model's parameters. Finally, we investigate the possibility of detecting Private Higgs dark matter indirectly via the observation of anomalous gamma rays originating from the galactic halo. We show that a substantial flux of photons can be produced from the annihilation of Private Higgs dark matter such that, if there is considerable clumping of dark matter in the galactic halo, the flux of these gamma rays could be observed by ground-based telescope arrays such as VERITAS and HESS.
2308.10789
Monojit Ghosh
Dinesh Kumar Singha, Rudra Majhi, Lipsarani Panda, Monojit Ghosh, Rukmani Mohanta
Study of Scalar Non Standard Interaction at Protvino to Super-ORCA experiment
24 pages, 15 figures, 4 tables, Includes analytical expression for appearance channel probability
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we have studied the phenomenon of non-standard interaction mediated by a scalar field (SNSI) in the context of P2SO experiment and compared its sensitivity with DUNE. In particular, we have studied the capability of these two experiments to put bounds on the diagonal SNSI parameters i.e., $\eta_{ee}$, $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ and studied the impact of these parameters on the determination of neutrino mass ordering, octant of $\theta_{23}$ and CP violation (CPV). In our analysis we find that, the parameter $\Delta m^2_{31}$ has a non-trivial role if one wants estimate the bounds on $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ assuming SNSI does not exist in nature. Our results show that sensitivity of P2SO and DUNE to constraint $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ are similar whereas the sensitivity of DUNE is slightly better for $\eta_{ee}$. We find that the mass ordering and CPV sensitivities are mostly affected by $\eta_{ee}$ compared to $\eta_{\mu \mu}$ and $\eta_{\tau \tau}$ if one assumes SNSI exists in nature. On the other hand, octant sensitivity is mostly affected by $\eta_{\mu \mu}$ and $\eta_{\tau \tau}$. These sensitivities can be either higher or lower than the standard three flavour scenario depending on the relative sign of the SNSI parameters. Regarding the precision of atmospheric mixing parameters, we find that the precision of $\theta_{23}$ deteriorates significantly in the presence of $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$.
[ { "created": "Mon, 21 Aug 2023 15:32:30 GMT", "version": "v1" }, { "created": "Thu, 11 Apr 2024 19:14:35 GMT", "version": "v2" } ]
2024-04-15
[ [ "Singha", "Dinesh Kumar", "" ], [ "Majhi", "Rudra", "" ], [ "Panda", "Lipsarani", "" ], [ "Ghosh", "Monojit", "" ], [ "Mohanta", "Rukmani", "" ] ]
In this paper we have studied the phenomenon of non-standard interaction mediated by a scalar field (SNSI) in the context of P2SO experiment and compared its sensitivity with DUNE. In particular, we have studied the capability of these two experiments to put bounds on the diagonal SNSI parameters i.e., $\eta_{ee}$, $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ and studied the impact of these parameters on the determination of neutrino mass ordering, octant of $\theta_{23}$ and CP violation (CPV). In our analysis we find that, the parameter $\Delta m^2_{31}$ has a non-trivial role if one wants estimate the bounds on $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ assuming SNSI does not exist in nature. Our results show that sensitivity of P2SO and DUNE to constraint $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$ are similar whereas the sensitivity of DUNE is slightly better for $\eta_{ee}$. We find that the mass ordering and CPV sensitivities are mostly affected by $\eta_{ee}$ compared to $\eta_{\mu \mu}$ and $\eta_{\tau \tau}$ if one assumes SNSI exists in nature. On the other hand, octant sensitivity is mostly affected by $\eta_{\mu \mu}$ and $\eta_{\tau \tau}$. These sensitivities can be either higher or lower than the standard three flavour scenario depending on the relative sign of the SNSI parameters. Regarding the precision of atmospheric mixing parameters, we find that the precision of $\theta_{23}$ deteriorates significantly in the presence of $\eta_{\mu\mu}$ and $\eta_{\tau\tau}$.
1108.1799
Alan Kostelecky
Jorge S. Diaz and Alan Kostelecky
Lorentz- and CPT-violating models for neutrino oscillations
17 pages two-column REVTeX
Phys.Rev.D85:016013,2012
10.1103/PhysRevD.85.016013
IUHET 561, August 2011
hep-ph hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A class of calculable global models for neutrino oscillations based on Lorentz and CPT violation is presented. One simple example matches established neutrino data from accelerator, atmospheric, reactor, and solar experiments, using only two degrees of freedom instead of the usual five. A third degree of freedom appears in the model, and it naturally generates the MiniBooNE low-energy anomalies. More involved models in this class can also accommodate the LSND anomaly and neutrino-antineutrino differences of the MINOS type. The models predict some striking signals in various ongoing and future experiments.
[ { "created": "Mon, 8 Aug 2011 20:00:07 GMT", "version": "v1" } ]
2015-05-30
[ [ "Diaz", "Jorge S.", "" ], [ "Kostelecky", "Alan", "" ] ]
A class of calculable global models for neutrino oscillations based on Lorentz and CPT violation is presented. One simple example matches established neutrino data from accelerator, atmospheric, reactor, and solar experiments, using only two degrees of freedom instead of the usual five. A third degree of freedom appears in the model, and it naturally generates the MiniBooNE low-energy anomalies. More involved models in this class can also accommodate the LSND anomaly and neutrino-antineutrino differences of the MINOS type. The models predict some striking signals in various ongoing and future experiments.