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hep-ph/0311251
Jorge Portoles
J. Portoles, P.D. Ruiz-Femenia (IFIC, Valencia)
The Hadronic Cross-Section in the Resonance Energy Region
6 pages, 5 figures. To appear in the Proceedings of the Workshop on Hadronic Cross-Section at Low Energy (SIGHAD03), 8th-10th October 2003, Pisa (Italy)
null
10.1016/S0920-5632(04)00025-8
IFIC/03-53
hep-ph
null
We study the hadronic vacuum polarization in the resonance energy region, using the framework given by the Resonance Effective Theory of QCD. We consider the incorporation of vector-pseudoscalar meson loops that give, inclusively, three and four pseudoscalar meson cuts. After resummation we achieve a QCD-based inclusive parameterization of the correlator, hence of the hadronic cross-section in the energy region populated by resonances.
[ { "created": "Thu, 20 Nov 2003 10:48:44 GMT", "version": "v1" } ]
2009-11-10
[ [ "Portoles", "J.", "", "IFIC, Valencia" ], [ "Ruiz-Femenia", "P. D.", "", "IFIC, Valencia" ] ]
We study the hadronic vacuum polarization in the resonance energy region, using the framework given by the Resonance Effective Theory of QCD. We consider the incorporation of vector-pseudoscalar meson loops that give, inclusively, three and four pseudoscalar meson cuts. After resummation we achieve a QCD-based inclusive parameterization of the correlator, hence of the hadronic cross-section in the energy region populated by resonances.
hep-ph/0203021
Paul F. Harrison
P.F. Harrison and W.G. Scott
Neutrino Matter Effect Invariants and the Observables of Neutrino Oscillations
11 pages, no figures. Add 3 new references at number 7. Correct a few typos
Phys.Lett. B535 (2002) 229-235
10.1016/S0370-2693(02)01764-1
RAL-TR-2002-006
hep-ph
null
We generalise our previous observation on the invariance of the Jarlskog determinant to matter effects in neutrino oscillations. Within the context of standard neutrino oscillation theory with matter effects, we present the complete set of (five) matter invariant observables for neutrino propagation in matter. We give some examples of their application.
[ { "created": "Mon, 4 Mar 2002 20:06:21 GMT", "version": "v1" }, { "created": "Mon, 29 Apr 2002 23:39:38 GMT", "version": "v2" } ]
2009-11-07
[ [ "Harrison", "P. F.", "" ], [ "Scott", "W. G.", "" ] ]
We generalise our previous observation on the invariance of the Jarlskog determinant to matter effects in neutrino oscillations. Within the context of standard neutrino oscillation theory with matter effects, we present the complete set of (five) matter invariant observables for neutrino propagation in matter. We give some examples of their application.
0909.1754
Alfredo Aranda
Alfredo Aranda, J. Lorenzo Diaz-Cruz, Ernest Ma, Roberto Noriega, and Jose Wudka
Asymmetric Higgs Sector and Neutrino Mass in an SU(2)_R Model
17 pages, 1 figure. FCNC bounds corrected. Additional references included
Phys.Rev.D80:115003,2009
10.1103/PhysRevD.80.115003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The asymmetric Higgs sector of one $SU(2)_L \times SU(2)_R$ bidoublet $(\phi_1^0,\phi_1^-;\phi_2^+,\phi_2^0)$ and one $SU(2)_R$ doublet [but no $SU(2)_L$ doublet] is considered in a nonsupersymmetric left-right extension of the standard model (SM) of particle interactions. The inverse seesaw mechanism for neutrino mass is naturally implemented with the addition of fermion singlets, allowing thereby the possibility of breaking $SU(2)_R$ at the TeV scale. In the limit $v_2 = < \phi_2^0 > = 0$, the unavoidable flavor-changing neutral Higgs couplings to quarks are studied and shown to be naturally suppressed in $K-\bar{K}$ and $B-\bar{B}$ mixing, as well as in $b \to s \gamma$. All particles are consistent with having masses less than 1 TeV, and could be observable at the Large Hadron Collider (LHC).
[ { "created": "Wed, 9 Sep 2009 17:45:58 GMT", "version": "v1" }, { "created": "Mon, 26 Oct 2009 08:18:15 GMT", "version": "v2" } ]
2009-12-14
[ [ "Aranda", "Alfredo", "" ], [ "Diaz-Cruz", "J. Lorenzo", "" ], [ "Ma", "Ernest", "" ], [ "Noriega", "Roberto", "" ], [ "Wudka", "Jose", "" ] ]
The asymmetric Higgs sector of one $SU(2)_L \times SU(2)_R$ bidoublet $(\phi_1^0,\phi_1^-;\phi_2^+,\phi_2^0)$ and one $SU(2)_R$ doublet [but no $SU(2)_L$ doublet] is considered in a nonsupersymmetric left-right extension of the standard model (SM) of particle interactions. The inverse seesaw mechanism for neutrino mass is naturally implemented with the addition of fermion singlets, allowing thereby the possibility of breaking $SU(2)_R$ at the TeV scale. In the limit $v_2 = < \phi_2^0 > = 0$, the unavoidable flavor-changing neutral Higgs couplings to quarks are studied and shown to be naturally suppressed in $K-\bar{K}$ and $B-\bar{B}$ mixing, as well as in $b \to s \gamma$. All particles are consistent with having masses less than 1 TeV, and could be observable at the Large Hadron Collider (LHC).
hep-ph/9910500
Chung Kao
V. Barger, K. Cheung, T. Han, C. Kao, T. Plehn, and R.-J. Zhang (University of Wisconsin--Madison and University of California--Davis)
Physics Potential of a Tevatron Tripler
Version to appear in Physics Letters B
Phys.Lett.B478:224-230,2000
10.1016/S0370-2693(00)00262-8
MADPH-99-1140 and UCD-99-21
hep-ph
null
We explore the capabilities for new physics discovery in proton-antiproton collisions at 5.4 TeV center-of-mass energy with luminosity $10^{33} cm^{-2} s^{-1}$ at a Tripler upgrade of the Tevatron collider. The prospects are robust for the usual Higgs boson and supersymmetry benchmarks. With an integrated luminosity of 40 fb$^{-1}$, discoveries at 5$\sigma$ could be made for a standard Higgs boson of mass $\alt 680$ GeV (600 GeV for 10 fb$^{-1}$), a lighter chargino of mass $\alt 380$ GeV, and an extra $Z$ boson of mass $\alt 2.6$ TeV; four-fermion contact interactions from new physics with scale $\alt 74$ TeV could be excluded at the 95% confidence level.
[ { "created": "Wed, 27 Oct 1999 21:43:50 GMT", "version": "v1" }, { "created": "Thu, 24 Feb 2000 21:14:36 GMT", "version": "v2" } ]
2009-09-15
[ [ "Barger", "V.", "", "University of Wisconsin--Madison and University of California--Davis" ], [ "Cheung", "K.", "", "University of Wisconsin--Madison and University of California--Davis" ], [ "Han", "T.", "", "University of Wisconsin--Madison and University of California--Davis" ], [ "Kao", "C.", "", "University of Wisconsin--Madison and University of California--Davis" ], [ "Plehn", "T.", "", "University of Wisconsin--Madison and University of California--Davis" ], [ "Zhang", "R. -J.", "", "University of Wisconsin--Madison and University of California--Davis" ] ]
We explore the capabilities for new physics discovery in proton-antiproton collisions at 5.4 TeV center-of-mass energy with luminosity $10^{33} cm^{-2} s^{-1}$ at a Tripler upgrade of the Tevatron collider. The prospects are robust for the usual Higgs boson and supersymmetry benchmarks. With an integrated luminosity of 40 fb$^{-1}$, discoveries at 5$\sigma$ could be made for a standard Higgs boson of mass $\alt 680$ GeV (600 GeV for 10 fb$^{-1}$), a lighter chargino of mass $\alt 380$ GeV, and an extra $Z$ boson of mass $\alt 2.6$ TeV; four-fermion contact interactions from new physics with scale $\alt 74$ TeV could be excluded at the 95% confidence level.
0712.3346
Seung-il Nam
Seung-il Nam and Hyun-Chul Kim
Pion electromagnetic form factor at finite density
4 pages, 2 figures, Talk given at the workshop Strangeness in multi-quark systems which was held during 26~28 November, 2007 in Sendai, Japan
null
null
YITP-07-96,PNU-NTG-11/2007
hep-ph
null
In this talk, we introduce an effective chiral action, derived from the instanton QCD vacuum configuration, in order to study the modification of mesonic properties in medium. We present our recent theoretical results on the electromagnetic from factor and rho-meson mass shift at finite density. We observe that the rho-meson mass is dropped by about 10%: m*_rho/m_rho ~ 1-0.12 mu_B/mu_0, which is compatible with that estimated by the QCD sum rule as well as by Brown and Rho.
[ { "created": "Thu, 20 Dec 2007 08:58:38 GMT", "version": "v1" } ]
2007-12-21
[ [ "Nam", "Seung-il", "" ], [ "Kim", "Hyun-Chul", "" ] ]
In this talk, we introduce an effective chiral action, derived from the instanton QCD vacuum configuration, in order to study the modification of mesonic properties in medium. We present our recent theoretical results on the electromagnetic from factor and rho-meson mass shift at finite density. We observe that the rho-meson mass is dropped by about 10%: m*_rho/m_rho ~ 1-0.12 mu_B/mu_0, which is compatible with that estimated by the QCD sum rule as well as by Brown and Rho.
1911.00597
German F. R. Sborlini
German F. R. Sborlini
Analysis of singularities and the four-dimensional representation of physical observables within the LTD formalism
7 pages, 1 figure. Contribution to the Proceedings of the EPS-HEP 2019 Conference
PoS(EPS-HEP2019)539
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the past years, we have been developing a novel technique, called Four-Dimensional Unsubtraction (FDU) which aims to obtain purely four-dimensional representations of the matrix elements contributing to physical observables. In this talk, we describe the application of the loop-tree duality (LTD) theorem to represent loop amplitudes in terms of tree-level like objects, focusing on the origin of possible singularities of scattering amplitudes. In particular, we analyze the regions responsible of infrared and threshold singularities. With this information, we aim to extend the FDU formalism to NNLO and beyond.
[ { "created": "Fri, 1 Nov 2019 21:39:09 GMT", "version": "v1" } ]
2019-11-05
[ [ "Sborlini", "German F. R.", "" ] ]
In the past years, we have been developing a novel technique, called Four-Dimensional Unsubtraction (FDU) which aims to obtain purely four-dimensional representations of the matrix elements contributing to physical observables. In this talk, we describe the application of the loop-tree duality (LTD) theorem to represent loop amplitudes in terms of tree-level like objects, focusing on the origin of possible singularities of scattering amplitudes. In particular, we analyze the regions responsible of infrared and threshold singularities. With this information, we aim to extend the FDU formalism to NNLO and beyond.
2004.02899
Abhishek Banerjee
Abhishek Banerjee, Hyungjin Kim, Oleksii Matsedonskyi, Gilad Perez, and Marianna S. Safronova
Probing the Relaxed Relaxion at the Luminosity and Precision Frontiers
29 pages, 7 figures, 1 Table v2: Table added. Matches the journal version
JHEP 07(2020)153
10.1007/JHEP07(2020)153
null
hep-ph physics.atom-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cosmological relaxation of the electroweak scale is an attractive scenario addressing the gauge hierarchy problem. Its main actor, the relaxion, is a light spin-zero field which dynamically relaxes the Higgs mass with respect to its natural large value. We show that the relaxion is generically stabilized at a special position in the field space, which leads to suppression of its mass and potentially unnatural values for the model's effective low-energy couplings. In particular, we find that the relaxion mixing with the Higgs can be several orders of magnitude above its naive naturalness bound. Low energy observers may thus find the relaxion theory being fine-tuned although the relaxion scenario itself is constructed in a technically natural way. More generally, we identify the lower and upper bounds on the mixing angle. We examine the experimental implications of the above observations at the luminosity and precision frontiers. A particular attention is given to the impressive ability of future nuclear clocks to search for rapidly oscillating scalar ultra-light dark matter, where the future projected sensitivity is presented.
[ { "created": "Mon, 6 Apr 2020 18:00:05 GMT", "version": "v1" }, { "created": "Mon, 27 Jul 2020 14:35:19 GMT", "version": "v2" } ]
2020-07-28
[ [ "Banerjee", "Abhishek", "" ], [ "Kim", "Hyungjin", "" ], [ "Matsedonskyi", "Oleksii", "" ], [ "Perez", "Gilad", "" ], [ "Safronova", "Marianna S.", "" ] ]
Cosmological relaxation of the electroweak scale is an attractive scenario addressing the gauge hierarchy problem. Its main actor, the relaxion, is a light spin-zero field which dynamically relaxes the Higgs mass with respect to its natural large value. We show that the relaxion is generically stabilized at a special position in the field space, which leads to suppression of its mass and potentially unnatural values for the model's effective low-energy couplings. In particular, we find that the relaxion mixing with the Higgs can be several orders of magnitude above its naive naturalness bound. Low energy observers may thus find the relaxion theory being fine-tuned although the relaxion scenario itself is constructed in a technically natural way. More generally, we identify the lower and upper bounds on the mixing angle. We examine the experimental implications of the above observations at the luminosity and precision frontiers. A particular attention is given to the impressive ability of future nuclear clocks to search for rapidly oscillating scalar ultra-light dark matter, where the future projected sensitivity is presented.
1008.0280
Sacha Davidson
Michael Carpentier, Sacha Davidson
Constraints on two-lepton, two quark operators
Modified presentation (to constrain coefficients of four fermion interactions, rather than gauge invariant operators), some numbers corrected, and minor changes. 28 pages, 18 tables
Eur.Phys.J.C70:1071-1090,2010
10.1140/epjc/s10052-010-1482-4
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Physics from beyond the Standard Model, such as leptoquarks, can induce four fermion operators involving a quark, an anti-quark, a lepton and an anti-lepton. We update the (flavour dependent) constraints on the coefficients of such interactions, arising from collider searches for contact interactions, meson decays and other rare processes. We then make naive estimates for the magnitude of the coefficients, as could arise in texture models or from inverse hierarchies in the kinetic term coefficients. These estimates suggest that rare Kaon decays could be a good place to look for such operators.
[ { "created": "Mon, 2 Aug 2010 11:43:24 GMT", "version": "v1" }, { "created": "Sun, 15 Aug 2010 05:52:39 GMT", "version": "v2" } ]
2010-12-15
[ [ "Carpentier", "Michael", "" ], [ "Davidson", "Sacha", "" ] ]
Physics from beyond the Standard Model, such as leptoquarks, can induce four fermion operators involving a quark, an anti-quark, a lepton and an anti-lepton. We update the (flavour dependent) constraints on the coefficients of such interactions, arising from collider searches for contact interactions, meson decays and other rare processes. We then make naive estimates for the magnitude of the coefficients, as could arise in texture models or from inverse hierarchies in the kinetic term coefficients. These estimates suggest that rare Kaon decays could be a good place to look for such operators.
hep-ph/0607299
Andre Peshier
A. Peshier
Collisional jet quenching becomes probable
5 figures
Phys.Rev.C75:034906,2007
10.1103/PhysRevC.75.034906
null
hep-ph nucl-th
null
It was argued recently that loop corrections to tree-level amplitudes are essential in the discussion of the collisional energy loss of energetic partons in the hot quark gluon plasma: Instead of $dE_{\rm coll}^B/dx \sim \alpha^2 T^2 \ln(ET/m_D^2)$, as first derived by Bjorken (assuming a constant $\alpha$), the mean energy loss actually behaves as $dE_{\rm coll}/dx \sim \alpha(m_D^2)T^2$. Here we calculate, within this resummation-improved framework, the probability distribution functions (`quenching weights') of the collisional energy loss. First results from a Monte Carlo implementation of this probabilistic collisional quenching shed new light on the interpretation of jet suppression in heavy ion collisions.
[ { "created": "Thu, 27 Jul 2006 07:15:12 GMT", "version": "v1" } ]
2008-11-26
[ [ "Peshier", "A.", "" ] ]
It was argued recently that loop corrections to tree-level amplitudes are essential in the discussion of the collisional energy loss of energetic partons in the hot quark gluon plasma: Instead of $dE_{\rm coll}^B/dx \sim \alpha^2 T^2 \ln(ET/m_D^2)$, as first derived by Bjorken (assuming a constant $\alpha$), the mean energy loss actually behaves as $dE_{\rm coll}/dx \sim \alpha(m_D^2)T^2$. Here we calculate, within this resummation-improved framework, the probability distribution functions (`quenching weights') of the collisional energy loss. First results from a Monte Carlo implementation of this probabilistic collisional quenching shed new light on the interpretation of jet suppression in heavy ion collisions.
hep-ph/9601256
null
Wei Lu, Xue-Qian Li, Hai-Ming Hu
Manifestation of $s\to \Lambda$ fragmentation matrix elements via transverse $\Lambda$ polarization in unpolarized $e^-e^+$ annihilation
RevTex, 12 pages, typos corrected
Phys.Lett. B368 (1996) 281-290
10.1016/0370-2693(95)01512-4
BIHEP-96-07
hep-ph
null
Making use of the collinear expansion technique developed by Ellis, Furmanski and Petrozio, and the special propagator concept invented by Qiu, we present a factorization approach to the photon fragmentation tensor for the inclusive Lambda hyperon production. As a result, the structure function $\tilde F$, which is related to the transverse polarization of the inclusive Lambda hyperon in unpolarized electron-positron annihilation, is expressed as a combination of four parton fragmentation matrix elements. Since the inclusive $\Lambda$ production we considered is theoretically the simplest, our study can be taken as a question to the operatability and practability of the first nonleading QCD factorization theorem in the transverse $\Lambda$ polarization phenomena.
[ { "created": "Sat, 13 Jan 1996 04:01:07 GMT", "version": "v1" }, { "created": "Tue, 16 Jan 1996 18:39:18 GMT", "version": "v2" } ]
2019-08-15
[ [ "Lu", "Wei", "" ], [ "Li", "Xue-Qian", "" ], [ "Hu", "Hai-Ming", "" ] ]
Making use of the collinear expansion technique developed by Ellis, Furmanski and Petrozio, and the special propagator concept invented by Qiu, we present a factorization approach to the photon fragmentation tensor for the inclusive Lambda hyperon production. As a result, the structure function $\tilde F$, which is related to the transverse polarization of the inclusive Lambda hyperon in unpolarized electron-positron annihilation, is expressed as a combination of four parton fragmentation matrix elements. Since the inclusive $\Lambda$ production we considered is theoretically the simplest, our study can be taken as a question to the operatability and practability of the first nonleading QCD factorization theorem in the transverse $\Lambda$ polarization phenomena.
1909.01536
Rohoollah Mohammadi
Mehdi Abdi (IUT), Roohollah Mohammadi (INMOST & SoA-IPM), She-Sheng Xue (ICRANet) and Moslem Zarei (IUT)
Distinguishing Dirac from Majorana neutrinos in a microwave cavity
9 pages and 5figures
null
null
null
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a novel scheme for distinguishing between the Dirac and Majorana nature of neutrinos via interaction of a neutrino beam with microwave photons inside a cavity. We study the effective photon-photon polarization exchange induced by the photon-neutrino scattering. The quantum field theoretical studies of such effective picture are presented for both Dirac and Majorana neutrinos. Our phenomenological analyses show that the difference between Dirac and Majorana neutrinos can manifest itself in scattering rate of the photons. To enhance the effect a cavity scheme is employed. An experimental setup based on microwave cavities is then designed and simulated by finite element method to measure the scattering rate. Our results suggest that an experiment based on the current state-of-the-art technology will be able to probe the difference in about one year. However, it can be done in a few days by enhancing the neutrino beam flux or implementing with the near future equipments. Therefore, our work provides the possibility %puts the grounds for solving the long lasting puzzle of Dirac or Majorana nature of neutrinos.
[ { "created": "Wed, 4 Sep 2019 03:20:23 GMT", "version": "v1" } ]
2019-09-05
[ [ "Abdi", "Mehdi", "", "IUT" ], [ "Mohammadi", "Roohollah", "", "INMOST & SoA-IPM" ], [ "Xue", "She-Sheng", "", "ICRANet" ], [ "Zarei", "Moslem", "", "IUT" ] ]
We propose a novel scheme for distinguishing between the Dirac and Majorana nature of neutrinos via interaction of a neutrino beam with microwave photons inside a cavity. We study the effective photon-photon polarization exchange induced by the photon-neutrino scattering. The quantum field theoretical studies of such effective picture are presented for both Dirac and Majorana neutrinos. Our phenomenological analyses show that the difference between Dirac and Majorana neutrinos can manifest itself in scattering rate of the photons. To enhance the effect a cavity scheme is employed. An experimental setup based on microwave cavities is then designed and simulated by finite element method to measure the scattering rate. Our results suggest that an experiment based on the current state-of-the-art technology will be able to probe the difference in about one year. However, it can be done in a few days by enhancing the neutrino beam flux or implementing with the near future equipments. Therefore, our work provides the possibility %puts the grounds for solving the long lasting puzzle of Dirac or Majorana nature of neutrinos.
2008.04249
James Howarth
James Howarth
Elastic Potential: A proposal to discover elastic production of top quarks at the Large Hadron Collider
7 pages, 3 figures
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
In this letter, I present the motivation and an example analysis method for discovering the elastic production of top-quark pairs at the LHC using forward proton tags, including an overview of the current theoretical tools and experimental acceptance. I show that it is possible to discover the semi-elastic process with only 300 pb${^{-1}}$ of data but that the fully-elastic case is currently out of reach. I also illustrate how the use of forward proton tags can result in limits on the branching ratio for flavor changing neutral current decays of the top quark of the form $t\rightarrow u\gamma$ and $t\rightarrow c\gamma$ of $<0.39\cdot10^{-5}$ and $<0.97\cdot10^{-5}$, respectively, both of which would surpass the existing world limits by at least an order of magnitude.
[ { "created": "Mon, 10 Aug 2020 16:41:38 GMT", "version": "v1" } ]
2020-08-11
[ [ "Howarth", "James", "" ] ]
In this letter, I present the motivation and an example analysis method for discovering the elastic production of top-quark pairs at the LHC using forward proton tags, including an overview of the current theoretical tools and experimental acceptance. I show that it is possible to discover the semi-elastic process with only 300 pb${^{-1}}$ of data but that the fully-elastic case is currently out of reach. I also illustrate how the use of forward proton tags can result in limits on the branching ratio for flavor changing neutral current decays of the top quark of the form $t\rightarrow u\gamma$ and $t\rightarrow c\gamma$ of $<0.39\cdot10^{-5}$ and $<0.97\cdot10^{-5}$, respectively, both of which would surpass the existing world limits by at least an order of magnitude.
2007.14426
Dmitry Zhuridov Dr. habil.
Dmitry Zhuridov, Jan T. Sobczyk, Cezary Juszczak and Kajetan Niewczas
Monte Carlo event generation of neutrino-electron scattering
16 pages, 9 figures; v2: minor changes, version published in JPG
null
10.1088/1361-6471/abdade
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe an extension of the NuWro Monte Carlo neutrino event generator with the neutrino-electron scattering processes. This new dynamical channel includes the charged current and neutral current interactions, together with their interference, for $\nu_\ell e$ and $\bar\nu_\ell e$ ($\ell=e,\mu,\tau$) scatterings, resulting in ten possible final states. We illustrate the performance of the new functionality on few physical examples, including an estimation of the background in the T2K $\nu_\mu\rightarrow\nu_e$ oscillation experiment. We show that the background events arising from the neutrino-electron interactions occupy mostly a distinct region of the phase space and can be easily separated.
[ { "created": "Tue, 28 Jul 2020 18:24:46 GMT", "version": "v1" }, { "created": "Mon, 28 Aug 2023 10:38:12 GMT", "version": "v2" } ]
2023-08-29
[ [ "Zhuridov", "Dmitry", "" ], [ "Sobczyk", "Jan T.", "" ], [ "Juszczak", "Cezary", "" ], [ "Niewczas", "Kajetan", "" ] ]
We describe an extension of the NuWro Monte Carlo neutrino event generator with the neutrino-electron scattering processes. This new dynamical channel includes the charged current and neutral current interactions, together with their interference, for $\nu_\ell e$ and $\bar\nu_\ell e$ ($\ell=e,\mu,\tau$) scatterings, resulting in ten possible final states. We illustrate the performance of the new functionality on few physical examples, including an estimation of the background in the T2K $\nu_\mu\rightarrow\nu_e$ oscillation experiment. We show that the background events arising from the neutrino-electron interactions occupy mostly a distinct region of the phase space and can be easily separated.
2402.03426
David Dunsky
David I. Dunsky, Marius Kongsore
Primordial Black Holes from Axion Domain Wall Collapse
41 + 8 pages; 17 + 5 figures; v3: Added figure showing collapse of aspherical wall. Matches published version
null
10.1007/JHEP06(2024)198
null
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
The QCD axion can solve the Strong CP Problem and be the dark matter of our universe. If the PQ symmetry breaking scale associated with the axion is below the inflationary reheating temperature, axion strings and domain walls populate the universe. Most of these strings and walls decay away into axion dark matter, but a small subset of the walls will be self-enclosed surfaces that are not attached to any strings. These enclosed walls can collapse in on themselves, compressing a large amount of energy into a small volume and potentially forming primordial black holes (PBHs). We study the number density and dynamics of these self-enclosed walls, taking into account their size distribution, Hubble expansion, asphericities, and all stages of domain wall dynamics using a combination of semi-analytic and numerical approaches. We find that axion models with a high axion decay constant $f_a$, such as those of interest in early matter-dominated cosmologies, yield a PBH abundance potentially observable by future gravitational lensing surveys. We note that the formalism developed here is also useful for predicting relic PBH abundances in other models that exhibit unstable domain walls.
[ { "created": "Mon, 5 Feb 2024 19:00:00 GMT", "version": "v1" }, { "created": "Sat, 9 Mar 2024 22:00:54 GMT", "version": "v2" }, { "created": "Mon, 17 Jun 2024 14:11:41 GMT", "version": "v3" } ]
2024-07-04
[ [ "Dunsky", "David I.", "" ], [ "Kongsore", "Marius", "" ] ]
The QCD axion can solve the Strong CP Problem and be the dark matter of our universe. If the PQ symmetry breaking scale associated with the axion is below the inflationary reheating temperature, axion strings and domain walls populate the universe. Most of these strings and walls decay away into axion dark matter, but a small subset of the walls will be self-enclosed surfaces that are not attached to any strings. These enclosed walls can collapse in on themselves, compressing a large amount of energy into a small volume and potentially forming primordial black holes (PBHs). We study the number density and dynamics of these self-enclosed walls, taking into account their size distribution, Hubble expansion, asphericities, and all stages of domain wall dynamics using a combination of semi-analytic and numerical approaches. We find that axion models with a high axion decay constant $f_a$, such as those of interest in early matter-dominated cosmologies, yield a PBH abundance potentially observable by future gravitational lensing surveys. We note that the formalism developed here is also useful for predicting relic PBH abundances in other models that exhibit unstable domain walls.
1510.01824
Jihn E. Kim
Jihn E. Kim
Towards unification of GUT families
19 pages, with 8 figures, talk at Planck 2015, Ioannina, Greece
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I discuss the mere 5 % of atoms in the cosmic energy pie. It is basically the chiral matter problem. Then, I review the chiral matter problem from a grand unification (GUT) point of view, and point out that anti-SU(N), easily implementable in string compactification, is a possibility. Here `anti-' means that the GUT group breaking is through the anti-symmetric tensor field(s), e.g. <\Phi^{[AB]}>= <\Phi_{[AB]}>. We argued for an anti-SU(7) [= SU(7) x U(1)] families-unification model from a Z(12-I) orbifold compactification. The Z(12-I) orbifold is briefly discussed and the multiplicity 2 in the T3 twisted sector is the key obtaining three chiral families. Yukawa coupling structure is shown to be promising. A numerical study shows that the anti-SU(7) model satisfies the CKM fit. It is shown that the doublet-triplet splitting is obtained naturally, where the dominant process for proton decay is by the exchange of GUT scale gauge bosons such that proton to pi-zero plus positron is the dominant channel.
[ { "created": "Wed, 7 Oct 2015 05:04:03 GMT", "version": "v1" } ]
2015-10-08
[ [ "Kim", "Jihn E.", "" ] ]
I discuss the mere 5 % of atoms in the cosmic energy pie. It is basically the chiral matter problem. Then, I review the chiral matter problem from a grand unification (GUT) point of view, and point out that anti-SU(N), easily implementable in string compactification, is a possibility. Here `anti-' means that the GUT group breaking is through the anti-symmetric tensor field(s), e.g. <\Phi^{[AB]}>= <\Phi_{[AB]}>. We argued for an anti-SU(7) [= SU(7) x U(1)] families-unification model from a Z(12-I) orbifold compactification. The Z(12-I) orbifold is briefly discussed and the multiplicity 2 in the T3 twisted sector is the key obtaining three chiral families. Yukawa coupling structure is shown to be promising. A numerical study shows that the anti-SU(7) model satisfies the CKM fit. It is shown that the doublet-triplet splitting is obtained naturally, where the dominant process for proton decay is by the exchange of GUT scale gauge bosons such that proton to pi-zero plus positron is the dominant channel.
1509.04898
Vladimir V. Anisovich
V.V. Anisovich, M.A. Matveev, J. Nyiri, A.V. Sarantsev, A.N. Semenova
Non-strange and strange pentaquarks with hidden charm
8 pages
International Journal of Modern Physics A Vol. 30 (2015) 1550190
10.1142/S0217751X15501900
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Non-strange and strange pentaquaks with hidden charm are considered as diquark-diquark-antiquark composite systems. Spin and isospin content of such exotic states is discussed and masses are evaluated.
[ { "created": "Wed, 16 Sep 2015 12:14:21 GMT", "version": "v1" } ]
2015-11-18
[ [ "Anisovich", "V. V.", "" ], [ "Matveev", "M. A.", "" ], [ "Nyiri", "J.", "" ], [ "Sarantsev", "A. V.", "" ], [ "Semenova", "A. N.", "" ] ]
Non-strange and strange pentaquaks with hidden charm are considered as diquark-diquark-antiquark composite systems. Spin and isospin content of such exotic states is discussed and masses are evaluated.
hep-ph/9209271
null
M. Neubert, Z. Ligeti and Y. Nir
QCD Sum Rule Analysis of the Subleading Isgur-Wise Form Factor $\chi_2(v\cdot v')$
(10 pages, REVTEX, 2 figures not included) SLAC-PUB-5915, WIS-92/70/Sep-PH
Phys.Lett.B301:101-107,1993
10.1016/0370-2693(93)90728-Z
null
hep-ph
null
We present a QCD sum rule calculation of the spin-symmetry violating universal function $\chi_2(v\cdot v')$, which appears at order $1/m_Q$ in the heavy quark expansion of meson form factors. This function vanishes in the standard approximation, where radiative effects are neglected. For the first time, the complete set of diagrams arising at order $\alpha_s$ is evaluated. In particular, we find $\chi_2(1) = -(3.8\pm 0.4)\%$ at zero recoil, indicating that $1/m_Q$ corrections induced by the chromo-magnetic moment operator are small.
[ { "created": "Wed, 23 Sep 1992 18:08:00 GMT", "version": "v1" } ]
2010-11-01
[ [ "Neubert", "M.", "" ], [ "Ligeti", "Z.", "" ], [ "Nir", "Y.", "" ] ]
We present a QCD sum rule calculation of the spin-symmetry violating universal function $\chi_2(v\cdot v')$, which appears at order $1/m_Q$ in the heavy quark expansion of meson form factors. This function vanishes in the standard approximation, where radiative effects are neglected. For the first time, the complete set of diagrams arising at order $\alpha_s$ is evaluated. In particular, we find $\chi_2(1) = -(3.8\pm 0.4)\%$ at zero recoil, indicating that $1/m_Q$ corrections induced by the chromo-magnetic moment operator are small.
1509.07331
Jordy Vries de
J. de Vries, Ulf-G. Mei{\ss}ner
Violations of discrete space-time symmetries in chiral effective field theory
Review article commissioned for a special issue of the International Journal of Modern Physics E. v2: Published version
International Journal of Modern Physics E, Vol. 25 1641008 (2016)
10.1142/S0218301316410081
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review recent progress in the theoretical description of the violation of discrete space-time symmetries in hadronic and nuclear systems. We focus on parity-violating and time-reversal-conserving interactions which are induced by the Standard Model weak interaction, and on parity- and time-reversal-violating interactions which can be caused by a nonzero QCD theta term or by beyond-the-Standard Model physics. We discuss the origins of such interactions and review the development of the chiral effective field theory extension that includes discrete symmetry violations. We discuss the construction of symmetry-violating chiral Lagrangians and nucleon-nucleon potentials and their applications in few-body systems.
[ { "created": "Thu, 24 Sep 2015 12:09:53 GMT", "version": "v1" }, { "created": "Thu, 28 Apr 2016 07:58:33 GMT", "version": "v2" } ]
2016-04-29
[ [ "de Vries", "J.", "" ], [ "Meißner", "Ulf-G.", "" ] ]
We review recent progress in the theoretical description of the violation of discrete space-time symmetries in hadronic and nuclear systems. We focus on parity-violating and time-reversal-conserving interactions which are induced by the Standard Model weak interaction, and on parity- and time-reversal-violating interactions which can be caused by a nonzero QCD theta term or by beyond-the-Standard Model physics. We discuss the origins of such interactions and review the development of the chiral effective field theory extension that includes discrete symmetry violations. We discuss the construction of symmetry-violating chiral Lagrangians and nucleon-nucleon potentials and their applications in few-body systems.
0708.0174
Wanda Maria Alberico
P. Czerski, W.M. Alberico, S. Chiacchiera, A. De Pace, H. Hansen, A. Molinari, M. Nardi
HTL approach to the viscosity of quark plasma
9 pages, 3 figures
J.Phys.G36:025008,2009
10.1088/0954-3899/36/2/025008
null
hep-ph
null
The quark viscosity in the quark gluon plasma is evaluated in HTL approximation. The different contributions to the viscosity arising from the various components of the quark spectral function are discussed. The calculation is extended to finite values of the chemical potential.
[ { "created": "Wed, 1 Aug 2007 15:05:31 GMT", "version": "v1" }, { "created": "Sat, 22 Dec 2007 19:16:24 GMT", "version": "v2" } ]
2009-10-06
[ [ "Czerski", "P.", "" ], [ "Alberico", "W. M.", "" ], [ "Chiacchiera", "S.", "" ], [ "De Pace", "A.", "" ], [ "Hansen", "H.", "" ], [ "Molinari", "A.", "" ], [ "Nardi", "M.", "" ] ]
The quark viscosity in the quark gluon plasma is evaluated in HTL approximation. The different contributions to the viscosity arising from the various components of the quark spectral function are discussed. The calculation is extended to finite values of the chemical potential.
2205.15350
Qiang Li
Sitian Qian, Tianyi Yang, Sen Deng, Jie Xiao, Leyun Gao, Andrew Michael Levin, Qiang Li, Meng Lu, Zhengyun You
The physics case for neutrino-neutrino collisions
5 pages, 4 figures, Xsec plot, luminosity estimation updated; Further updates to address comments received
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Addressing the mass origin and properties of neutrinos is of strong interest to particle physics, baryogenesis and cosmology. Popular explanations involve physics beyond the standard model, for example, the dimension-5 Weinberg operator or heavy Majorana neutrinos arising from ``seesaw'' models. The current best direct limits on the electron neutrino mass, derived from nuclei beta decay or neutrinoless double beta decay processes, are at the sub-electronvolt level. Here we propose a novel neutrino neutrino collider where the neutrino beam is generated from TeV scale muon decays. Such collisions can happen between either neutrinos and anti-neutrinos, or neutrinos and neutrinos. We find that with a tiny integrated luminosity of about $10^{-5}$/fb we can already expect to observe direct neutrino anti-neutrino annihilation, $\nu\bar{\nu}\rightarrow {\rm Z}$, which also opens the door to explore neutrino related resonances $\nu\bar{\nu}\rightarrow {\rm X}$. The low luminosity requirement can accommodate a relatively large emittance muon beam. Such a device would also allow for probing heavy Majorana neutrino and effective Majorana neutrino mass through $\nu\nu\rightarrow {\rm H H}$ to a competitive level, for both electron and muon types.
[ { "created": "Mon, 30 May 2022 18:00:59 GMT", "version": "v1" }, { "created": "Tue, 14 Jun 2022 16:15:30 GMT", "version": "v2" }, { "created": "Fri, 26 Aug 2022 07:59:46 GMT", "version": "v3" }, { "created": "Mon, 27 Feb 2023 01:08:05 GMT", "version": "v4" }, { "created": "Sat, 9 Dec 2023 07:58:55 GMT", "version": "v5" } ]
2023-12-12
[ [ "Qian", "Sitian", "" ], [ "Yang", "Tianyi", "" ], [ "Deng", "Sen", "" ], [ "Xiao", "Jie", "" ], [ "Gao", "Leyun", "" ], [ "Levin", "Andrew Michael", "" ], [ "Li", "Qiang", "" ], [ "Lu", "Meng", "" ], [ "You", "Zhengyun", "" ] ]
Addressing the mass origin and properties of neutrinos is of strong interest to particle physics, baryogenesis and cosmology. Popular explanations involve physics beyond the standard model, for example, the dimension-5 Weinberg operator or heavy Majorana neutrinos arising from ``seesaw'' models. The current best direct limits on the electron neutrino mass, derived from nuclei beta decay or neutrinoless double beta decay processes, are at the sub-electronvolt level. Here we propose a novel neutrino neutrino collider where the neutrino beam is generated from TeV scale muon decays. Such collisions can happen between either neutrinos and anti-neutrinos, or neutrinos and neutrinos. We find that with a tiny integrated luminosity of about $10^{-5}$/fb we can already expect to observe direct neutrino anti-neutrino annihilation, $\nu\bar{\nu}\rightarrow {\rm Z}$, which also opens the door to explore neutrino related resonances $\nu\bar{\nu}\rightarrow {\rm X}$. The low luminosity requirement can accommodate a relatively large emittance muon beam. Such a device would also allow for probing heavy Majorana neutrino and effective Majorana neutrino mass through $\nu\nu\rightarrow {\rm H H}$ to a competitive level, for both electron and muon types.
hep-ph/0103132
Brigitte Vachon
Brigitte Vachon (University of Victoria, Canada)
Excited electron contribution to the e+e- -> \gamma\gamma cross-section
4 pages, 2 figures, use Revtex4 Correction to Equation 5
null
null
null
hep-ph
null
The differential cross-section for the process e+e- -> \gamma\gamma is calculated assuming the presence of excited electrons with a chiral magnetic coupling. This calculation permits constraining the excited electron coupling using the same theoretical framework as the one generally used for direct production searches.
[ { "created": "Tue, 13 Mar 2001 09:20:35 GMT", "version": "v1" }, { "created": "Wed, 28 Apr 2004 07:16:29 GMT", "version": "v2" } ]
2007-05-23
[ [ "Vachon", "Brigitte", "", "University of Victoria, Canada" ] ]
The differential cross-section for the process e+e- -> \gamma\gamma is calculated assuming the presence of excited electrons with a chiral magnetic coupling. This calculation permits constraining the excited electron coupling using the same theoretical framework as the one generally used for direct production searches.
hep-ph/9812490
Dieter Mueller
D. M\"uller (Univ. Regensburg)
Scheme dependence of NLO corrections to exclusive processes
RevTeX, 25 pages, 2 figures, 5 tables, minor changes, to be published in Phys. Rev. D
Phys.Rev. D59 (1999) 116003
10.1103/PhysRevD.59.116003
null
hep-ph
null
We apply the so-called conformal subtraction scheme to predict perturbatively exclusive processes beyond leading order. Taking into account evolution effects, we study the scheme dependence for the photon-to-pion transition form factor and the electromagnetic pion form factor at next-to-leading order for different pion distribution amplitudes. Relying on the conformally covariant operator product expansion and using the known higher order results for polarized deep inelastic scattering, we are able to predict perturbative corrections to the hard-scattering amplitude of the photon-to-pion transition form factor beyond next-to-leading order in the conformal scheme restricted to the conformal limit of the theory.
[ { "created": "Wed, 23 Dec 1998 20:36:53 GMT", "version": "v1" }, { "created": "Tue, 16 Mar 1999 09:39:23 GMT", "version": "v2" } ]
2009-10-31
[ [ "Müller", "D.", "", "Univ. Regensburg" ] ]
We apply the so-called conformal subtraction scheme to predict perturbatively exclusive processes beyond leading order. Taking into account evolution effects, we study the scheme dependence for the photon-to-pion transition form factor and the electromagnetic pion form factor at next-to-leading order for different pion distribution amplitudes. Relying on the conformally covariant operator product expansion and using the known higher order results for polarized deep inelastic scattering, we are able to predict perturbative corrections to the hard-scattering amplitude of the photon-to-pion transition form factor beyond next-to-leading order in the conformal scheme restricted to the conformal limit of the theory.
hep-ph/0110211
Nicola Fabiano
Nicola Fabiano, Giulia Pancheri
Two photon width of eta_c
4 Pages, 1 figure, use ws-p8-50x6-00.cls. To appear in the proceedings of the Photon 2001 Conference on The Structure and Interactions of the Photon, September 2nd-7th 2001, Ascona, Switzerland
null
10.1142/9789812777157_0059
null
hep-ph
null
We discuss the measured partial width of the pseudoscalar charmonium state, $\eta_c$, into two photons. Predictions from potential models are examined and compared with experimental values. Including radiative corrections, it is found that present measurements are compatible both with a QCD type potential and with a static Coulomb potential, with $\alpha_s$ evaluated at two loops. Results are also compared with those from $\jpsi$ data through the NRQCD model.
[ { "created": "Tue, 16 Oct 2001 10:51:04 GMT", "version": "v1" } ]
2017-08-23
[ [ "Fabiano", "Nicola", "" ], [ "Pancheri", "Giulia", "" ] ]
We discuss the measured partial width of the pseudoscalar charmonium state, $\eta_c$, into two photons. Predictions from potential models are examined and compared with experimental values. Including radiative corrections, it is found that present measurements are compatible both with a QCD type potential and with a static Coulomb potential, with $\alpha_s$ evaluated at two loops. Results are also compared with those from $\jpsi$ data through the NRQCD model.
1403.6791
Karim Ghorbani
Karim Ghorbani
Leading Chiral Logarithms of $K_{S} \to \gamma \gamma$ and $K_{S} \to \gamma~l^+ l^-$ at two Loops
v3: more references, typos corrected, version accepted for publication
Nucl.Phys. B885 (2014) 46-60
10.1016/j.nuclphysb.2014.05.020
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We obtain the leading divergences at two-loop order for the decays $K_{S} \to \gamma \gamma$ and $K_{S} \to \gamma~\l^+ \l^-$ using only one-loop diagrams. We then find the double chiral logarithmic corrections to the decay branching ratio of $K_{S} \to \gamma \gamma$ and to the decay rate for $K_{S} \to \gamma~\l^+ \l^-$. It turns out that these effects are numerically small and therefore make a very small enhancement on the branching ratio and decay rate. We also derive an expression for the corrections of type $\log \mu~\times$ LEC. Numerical analysis done for the process $K_{S} \to \gamma \gamma$ shows that these single logarithmic effects can be sizable but come with opposite signs with respect to the double chiral logarithms.
[ { "created": "Wed, 26 Mar 2014 18:56:50 GMT", "version": "v1" }, { "created": "Mon, 7 Apr 2014 09:01:35 GMT", "version": "v2" }, { "created": "Mon, 2 Jun 2014 17:11:13 GMT", "version": "v3" } ]
2014-07-31
[ [ "Ghorbani", "Karim", "" ] ]
We obtain the leading divergences at two-loop order for the decays $K_{S} \to \gamma \gamma$ and $K_{S} \to \gamma~\l^+ \l^-$ using only one-loop diagrams. We then find the double chiral logarithmic corrections to the decay branching ratio of $K_{S} \to \gamma \gamma$ and to the decay rate for $K_{S} \to \gamma~\l^+ \l^-$. It turns out that these effects are numerically small and therefore make a very small enhancement on the branching ratio and decay rate. We also derive an expression for the corrections of type $\log \mu~\times$ LEC. Numerical analysis done for the process $K_{S} \to \gamma \gamma$ shows that these single logarithmic effects can be sizable but come with opposite signs with respect to the double chiral logarithms.
hep-ph/9708343
Zoltan Trocsanyi
Zoltan Nagy and Zoltan Trocsanyi
Excluding light gluinos using four-jet LEP events: a next-to-leading order result
11 pages, 3 figures, 1 table revtex + aps,preprint,epsf,rotate styles
null
null
null
hep-ph
null
Based upon a next-to-leading order perturbative calculation of the four-jet production rate in electron-positron annihilation and assuming 8 % for the theoretical error emerging from hadronization effects in the $0.002\le \ycut \le 0.004$ range for the Durham clustering algorithm, we exclude the existence of the light gluinos at the 95 % confidence level.
[ { "created": "Wed, 13 Aug 1997 17:40:02 GMT", "version": "v1" } ]
2007-05-23
[ [ "Nagy", "Zoltan", "" ], [ "Trocsanyi", "Zoltan", "" ] ]
Based upon a next-to-leading order perturbative calculation of the four-jet production rate in electron-positron annihilation and assuming 8 % for the theoretical error emerging from hadronization effects in the $0.002\le \ycut \le 0.004$ range for the Durham clustering algorithm, we exclude the existence of the light gluinos at the 95 % confidence level.
2009.13188
Maxim Nefedov
Maxim A. Nefedov and Vladimir A. Saleev
High-Energy Factorization for Drell-Yan process in $pp$ and $p{\bar p}$ collisions with new Unintegrated PDFs
31 pages, 9 figures, 1 table
Phys. Rev. D 102, 114018 (2020)
10.1103/PhysRevD.102.114018
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The formalism for uniform description of Drell-Yan transverse-momentum spectrum is presented in a framework of High-Energy Factorization, which smoothly interpolates between Collins-Soper-Sterman formalism at $|{\bf q}_T|\ll Q$ and usual Collinear Parton Model at $|{\bf q}_T|\sim Q\ll \sqrt{S}$. The new formula for deriving Unintegrated Parton Distribution Functions(UPDFs) from collinear ones is introduced, which leads to excellent description of the shape of $Z$-boson $|{\bf q}_T|$-spectrum at high energies up to $|{\bf q}_T|/\sqrt{S}\simeq 0.02$. Description of normalized $|{\bf q}_T|$-distributions at low energies is achieved via the fit of non-perturbative parameters of quark UPDFs. Reasonable description of angular distributions of leptons in the dilepton center-of-mass frame is also obtained with new UPDFs.
[ { "created": "Mon, 28 Sep 2020 10:01:32 GMT", "version": "v1" } ]
2021-01-04
[ [ "Nefedov", "Maxim A.", "" ], [ "Saleev", "Vladimir A.", "" ] ]
The formalism for uniform description of Drell-Yan transverse-momentum spectrum is presented in a framework of High-Energy Factorization, which smoothly interpolates between Collins-Soper-Sterman formalism at $|{\bf q}_T|\ll Q$ and usual Collinear Parton Model at $|{\bf q}_T|\sim Q\ll \sqrt{S}$. The new formula for deriving Unintegrated Parton Distribution Functions(UPDFs) from collinear ones is introduced, which leads to excellent description of the shape of $Z$-boson $|{\bf q}_T|$-spectrum at high energies up to $|{\bf q}_T|/\sqrt{S}\simeq 0.02$. Description of normalized $|{\bf q}_T|$-distributions at low energies is achieved via the fit of non-perturbative parameters of quark UPDFs. Reasonable description of angular distributions of leptons in the dilepton center-of-mass frame is also obtained with new UPDFs.
1109.3717
Marco Zaro
Paolo Bolzoni, Fabio Maltoni, Sven-Olaf Moch, and Marco Zaro
Vector boson fusion at NNLO in QCD: SM Higgs and beyond
56 pages
Phys. Rev. D 85, 035002 (2012)
10.1103/PhysRevD.85.035002
DESY 11-153, CP3-11-28, LPN 11-51, SFB/CPP-11-50
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Weak vector boson fusion provides a unique channel to directly probe the mechanism of electroweak symmetry breaking at hadron colliders. We present a method that allows to calculate total cross sections to next-to-next-to-leading order (NNLO) in QCD for an arbitrary V* V* -> X process, the so-called structure function approach. By discussing the case of Higgs production in detail, we estimate several classes of previously neglected contributions and we argue that such method is accurate at a precision level well above the typical residual scale and PDF uncertainties at NNLO. Predictions for cross sections at the Tevatron and the LHC are presented for a variety of cases: the Standard Model Higgs (including anomalous couplings), neutral and charged scalars in extended Higgs sectors and (fermiophobic) vector resonance production. Further results can be easily obtained through the public use of the VBF@NNLO code.
[ { "created": "Fri, 16 Sep 2011 20:07:46 GMT", "version": "v1" }, { "created": "Fri, 3 Feb 2012 08:19:15 GMT", "version": "v2" } ]
2015-03-19
[ [ "Bolzoni", "Paolo", "" ], [ "Maltoni", "Fabio", "" ], [ "Moch", "Sven-Olaf", "" ], [ "Zaro", "Marco", "" ] ]
Weak vector boson fusion provides a unique channel to directly probe the mechanism of electroweak symmetry breaking at hadron colliders. We present a method that allows to calculate total cross sections to next-to-next-to-leading order (NNLO) in QCD for an arbitrary V* V* -> X process, the so-called structure function approach. By discussing the case of Higgs production in detail, we estimate several classes of previously neglected contributions and we argue that such method is accurate at a precision level well above the typical residual scale and PDF uncertainties at NNLO. Predictions for cross sections at the Tevatron and the LHC are presented for a variety of cases: the Standard Model Higgs (including anomalous couplings), neutral and charged scalars in extended Higgs sectors and (fermiophobic) vector resonance production. Further results can be easily obtained through the public use of the VBF@NNLO code.
1703.09153
Hiroshi Okada
Cheng-Wei Chiang, Hiroshi Okada, Eibun Senaha
Dark Matter, Muon $g-2$, Electric Dipole Moments and $Z\to \ell_i^+ \ell_j^-$ in a One-Loop Induced Neutrino Model
28 pages, 10 figures, 1 table, version accepted by Phys. Rev. D; Typos in Eq.(II.39) are modified
Phys. Rev. D 96, 015002 (2017)
10.1103/PhysRevD.96.015002
NCTS-PH/1705
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study a simple one-loop induced neutrino mass model that contains both bosonic and fermionic dark matter candidates and has the capacity to explain the muon anomalous magnetic moment anomaly. We perform a comprehensive analysis by taking into account the relevant constraints of charged lepton flavor violation, electric dipole moments, and neutrino oscillation data. We examine the constraints from lepton flavor-changing $Z$ boson decays at one-loop level, particularly when the involved couplings contribute to the muon $g-2$. It is found that $\text{BR}(Z\to \mu\tau)\simeq (10^{-7}$ - $10^{-6})$ while $\text{BR}(\tau\to\mu\gamma)\lesssim 10^{-11}$ in the fermionic dark matter scenario. The former can be probed by the precision measurement of the $Z$ boson at future lepton colliders.
[ { "created": "Mon, 27 Mar 2017 15:50:48 GMT", "version": "v1" }, { "created": "Wed, 7 Jun 2017 23:48:57 GMT", "version": "v2" }, { "created": "Wed, 23 Jan 2019 06:18:25 GMT", "version": "v3" } ]
2019-01-24
[ [ "Chiang", "Cheng-Wei", "" ], [ "Okada", "Hiroshi", "" ], [ "Senaha", "Eibun", "" ] ]
We study a simple one-loop induced neutrino mass model that contains both bosonic and fermionic dark matter candidates and has the capacity to explain the muon anomalous magnetic moment anomaly. We perform a comprehensive analysis by taking into account the relevant constraints of charged lepton flavor violation, electric dipole moments, and neutrino oscillation data. We examine the constraints from lepton flavor-changing $Z$ boson decays at one-loop level, particularly when the involved couplings contribute to the muon $g-2$. It is found that $\text{BR}(Z\to \mu\tau)\simeq (10^{-7}$ - $10^{-6})$ while $\text{BR}(\tau\to\mu\gamma)\lesssim 10^{-11}$ in the fermionic dark matter scenario. The former can be probed by the precision measurement of the $Z$ boson at future lepton colliders.
hep-ph/9412379
Marek Olechowski
F.M. Borzumati, M. Olechowski and S. Pokorski
Constraints on the Minimal SUSY SO(10) Model from Cosmology and the $b\to s \gamma$ Decay
10 pages, latex, 5 figures (not included, available on request)
Phys.Lett.B349:311-318,1995
10.1016/0370-2693(95)00270-U
CERN-TH.7515/94
hep-ph
null
It is shown that the minimal supersymmetric SO(10) model with electroweak radiative breaking and universal soft mass terms at the GUT scale is strongly disfavoured by the combination of constraints from the $b\to s \gamma$ decay and the condition $\Omega h^2 < 1$ for the lightest (stable) neutralino. The constraints are, however, easily satisfied for certain class of supersymmetric SO(10) models with non--universal scalar masses which gives small supersymmetric corrections to the bottom quark mass and light higgsino--like neutralinos.
[ { "created": "Wed, 28 Dec 1994 14:58:57 GMT", "version": "v1" }, { "created": "Thu, 29 Dec 1994 08:44:25 GMT", "version": "v2" } ]
2011-01-27
[ [ "Borzumati", "F. M.", "" ], [ "Olechowski", "M.", "" ], [ "Pokorski", "S.", "" ] ]
It is shown that the minimal supersymmetric SO(10) model with electroweak radiative breaking and universal soft mass terms at the GUT scale is strongly disfavoured by the combination of constraints from the $b\to s \gamma$ decay and the condition $\Omega h^2 < 1$ for the lightest (stable) neutralino. The constraints are, however, easily satisfied for certain class of supersymmetric SO(10) models with non--universal scalar masses which gives small supersymmetric corrections to the bottom quark mass and light higgsino--like neutralinos.
0911.4577
Sudhanwa Patra
Sudhanwa Patra
Testable Leptogenesis in extended Standard Model
17 pages, 7 figures, corrected typos, references added.
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have proposed a new minimal extension of the Standard Model with a heavy Majorana fermion triplet($\Sigma$) and an extra scalar doublet($\eta$) so that the seesaw mechanism is radiative and can be accessible at upcoming accelerators. The origin of neutrino mass via the famous seesaw mechanism through the heavy Majorana fermion triplet has been discussed. We have proposed a mechanism of leptogenesis by the decay of the lightest neutral component of the fermion triplet into a Standard Model lepton doublet and an extra Higgs doublet. The important thing is that the leptogenesis scenario discussed in this letter can be of TeV scale and hence can be testable at Large Hadron Collider(LHC). We have also discussed a possible dark matter scenario in our model and the possible phenomenology of the fermion field $\Sigma$.
[ { "created": "Tue, 24 Nov 2009 08:54:17 GMT", "version": "v1" }, { "created": "Fri, 12 Mar 2010 12:56:18 GMT", "version": "v2" } ]
2015-03-13
[ [ "Patra", "Sudhanwa", "" ] ]
We have proposed a new minimal extension of the Standard Model with a heavy Majorana fermion triplet($\Sigma$) and an extra scalar doublet($\eta$) so that the seesaw mechanism is radiative and can be accessible at upcoming accelerators. The origin of neutrino mass via the famous seesaw mechanism through the heavy Majorana fermion triplet has been discussed. We have proposed a mechanism of leptogenesis by the decay of the lightest neutral component of the fermion triplet into a Standard Model lepton doublet and an extra Higgs doublet. The important thing is that the leptogenesis scenario discussed in this letter can be of TeV scale and hence can be testable at Large Hadron Collider(LHC). We have also discussed a possible dark matter scenario in our model and the possible phenomenology of the fermion field $\Sigma$.
2005.13549
Ye-Ling Zhou
Stephen F. King, Silvia Pascoli, Jessica Turner, Ye-Ling Zhou
Gravitational waves and proton decay: complementary windows into GUTs
10 pages, 3 figures, refs added and text polished, published in PRL
Phys. Rev. Lett. 126, 021802 (2021)
10.1103/PhysRevLett.126.021802
FERMILAB-PUB-20-187-T, IPPP/20/20
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Proton decay is a smoking gun signature of Grand Unified Theories (GUTs). Searches by Super-Kamiokande have resulted in stringent limits on the GUT symmetry breaking scale. The large-scale multipurpose neutrino experiments DUNE, Hyper-Kamiokande and JUNO will either discover proton decay or further push the symmetry breaking scale above $10^{16}$ GeV. Another possible observational consequence of GUTs is the formation of a cosmic string network produced during the breaking of the GUT to the Standard Model gauge group. The evolution of such a string network in the expanding Universe produces a stochastic background of gravitational waves which will be tested by a number of gravitational wave detectors over a wide frequency range. We demonstrate the non-trivial complementarity between the observation of proton decay and gravitational waves produced from cosmic strings in determining $SO(10)$ GUT breaking chains. We show that such observations could exclude $SO(10)$ breaking via flipped $SU(5)\times U(1)$ or standard $SU(5)$, while breaking via a Pati-Salam intermediate symmetry, or standard $SU(5)\times U(1)$, may be favoured if a large separation of energy scales associated with proton decay and cosmic strings is indicated. We note that recent results by the NANOGrav experiment have been interpreted as evidence for cosmic strings at a scale $\sim 10^{14}$ GeV. This would strongly point towards the existence of GUTs, with $SO(10)$ being the prime candidate. We show that the combination with already available constraints from proton decay allows to identify preferred symmetry breaking routes to the Standard Model.
[ { "created": "Wed, 27 May 2020 18:00:01 GMT", "version": "v1" }, { "created": "Fri, 25 Sep 2020 15:56:22 GMT", "version": "v2" }, { "created": "Mon, 28 Sep 2020 13:41:19 GMT", "version": "v3" }, { "created": "Mon, 18 Jan 2021 14:03:15 GMT", "version": "v4" } ]
2021-01-19
[ [ "King", "Stephen F.", "" ], [ "Pascoli", "Silvia", "" ], [ "Turner", "Jessica", "" ], [ "Zhou", "Ye-Ling", "" ] ]
Proton decay is a smoking gun signature of Grand Unified Theories (GUTs). Searches by Super-Kamiokande have resulted in stringent limits on the GUT symmetry breaking scale. The large-scale multipurpose neutrino experiments DUNE, Hyper-Kamiokande and JUNO will either discover proton decay or further push the symmetry breaking scale above $10^{16}$ GeV. Another possible observational consequence of GUTs is the formation of a cosmic string network produced during the breaking of the GUT to the Standard Model gauge group. The evolution of such a string network in the expanding Universe produces a stochastic background of gravitational waves which will be tested by a number of gravitational wave detectors over a wide frequency range. We demonstrate the non-trivial complementarity between the observation of proton decay and gravitational waves produced from cosmic strings in determining $SO(10)$ GUT breaking chains. We show that such observations could exclude $SO(10)$ breaking via flipped $SU(5)\times U(1)$ or standard $SU(5)$, while breaking via a Pati-Salam intermediate symmetry, or standard $SU(5)\times U(1)$, may be favoured if a large separation of energy scales associated with proton decay and cosmic strings is indicated. We note that recent results by the NANOGrav experiment have been interpreted as evidence for cosmic strings at a scale $\sim 10^{14}$ GeV. This would strongly point towards the existence of GUTs, with $SO(10)$ being the prime candidate. We show that the combination with already available constraints from proton decay allows to identify preferred symmetry breaking routes to the Standard Model.
0709.3450
Claudia Hagedorn
A. Blum, C. Hagedorn, M. Lindner
Fermion Masses and Mixings from Dihedral Flavor Symmetries with Preserved Subgroups
25 pages
Phys.Rev.D77:076004,2008
10.1103/PhysRevD.77.076004
null
hep-ph
null
We perform a systematic study of dihedral groups used as flavor symmetry. The key feature here is the fact that we do not allow the dihedral groups to be broken in an arbitrary way, but in all cases some (non-trivial) subgroup has to be preserved. In this way we arrive at only five possible (Dirac) mass matrix structures which can arise, if we require that the matrix has to have a non-vanishing determinant and that at least two of the three generations of left-handed (conjugate) fermions are placed into an irreducible two-dimensional representation of the flavor group. We show that there is no difference between the mass matrix structures for single- and double-valued dihedral groups. Furthermore, we comment on possible forms of Majorana mass matrices. As a first application we find a way to express the Cabibbo angle, i.e. the CKM matrix element |V_{us}|, in terms of group theory quantities only, the group index n, the representation index j and the index m_{u,d} of the different preserved subgroups in the up and down quark sector: |V_{us}|=|cos(pi(m_{u}-m_{d})j/n)| which is |cos(3 pi/7)| = 0.2225 for n=7, j=1, m_{u}=3 and m_{d}=0. We prove that two successful models which lead to maximal atmospheric mixing and vanishing theta_{13} in the lepton sector are based on the fact that the flavor symmetry is broken in the charged lepton, Dirac neutrino and Majorana neutrino sector down to different preserved subgroups whose mismatch results in the prediction of these mixing angles. This also demonstrates the power of preserved subgroups in connection with the prediction of mixing angles in the quark as well as in the lepton sector.
[ { "created": "Fri, 21 Sep 2007 14:28:00 GMT", "version": "v1" } ]
2008-11-26
[ [ "Blum", "A.", "" ], [ "Hagedorn", "C.", "" ], [ "Lindner", "M.", "" ] ]
We perform a systematic study of dihedral groups used as flavor symmetry. The key feature here is the fact that we do not allow the dihedral groups to be broken in an arbitrary way, but in all cases some (non-trivial) subgroup has to be preserved. In this way we arrive at only five possible (Dirac) mass matrix structures which can arise, if we require that the matrix has to have a non-vanishing determinant and that at least two of the three generations of left-handed (conjugate) fermions are placed into an irreducible two-dimensional representation of the flavor group. We show that there is no difference between the mass matrix structures for single- and double-valued dihedral groups. Furthermore, we comment on possible forms of Majorana mass matrices. As a first application we find a way to express the Cabibbo angle, i.e. the CKM matrix element |V_{us}|, in terms of group theory quantities only, the group index n, the representation index j and the index m_{u,d} of the different preserved subgroups in the up and down quark sector: |V_{us}|=|cos(pi(m_{u}-m_{d})j/n)| which is |cos(3 pi/7)| = 0.2225 for n=7, j=1, m_{u}=3 and m_{d}=0. We prove that two successful models which lead to maximal atmospheric mixing and vanishing theta_{13} in the lepton sector are based on the fact that the flavor symmetry is broken in the charged lepton, Dirac neutrino and Majorana neutrino sector down to different preserved subgroups whose mismatch results in the prediction of these mixing angles. This also demonstrates the power of preserved subgroups in connection with the prediction of mixing angles in the quark as well as in the lepton sector.
2003.05634
Jun-Kang He
Jun-Kang He and Chao-Jie Fan
Revisiting the $P$-wave charmonium radiative decays $h_{c}\rightarrow\gamma\eta^{(\prime)}$ with relativistic corrections
34 pages, 4 figures and 7 tables
Phys. Rev. D 103, 114006 (2021)
10.1103/PhysRevD.103.114006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $P$-wave charmonium decays $h_{c}\rightarrow\gamma\eta^{(\prime)}$ are revisited by taking into account relativistic corrections. The decay amplitudes are derived in the Bethe-Salpeter formalism, in which the involved one-loop integrals are evaluated analytically. Intriguingly, from both the quark-antiquark content and the gluonic content of $\eta^{(\prime)}$, the relativistic corrections make significant contributions to the decay rates of $h_{c}\rightarrow\gamma\eta^{(\prime)}$. By comparison with the leading-order contributions from the quark-antiquark content (one-loop level), the ones from the gluonic content (tree level) are also important, which is compatible with the conclusion obtained without relativistic corrections. Usually, for $\eta$ production processes, the predicted branching ratios are sensitive to the angle of $\eta-\eta^{\prime}$ mixing. As an illustration, using the Feldmann-Kroll-Stech result about the mixing angle $\phi=39.3^{\circ}\pm1.0^{\circ}$ as input, we find that the predicted ratio $R_{h_{c}}=\mathcal{B}(h_{c}\rightarrow\gamma\eta)/\mathcal{B}(h_{c}\rightarrow\gamma\eta^{\prime})$ is much smaller than the experiment measurement. While, with $\phi=33.5^{\circ}\pm0.9^{\circ}$ extracted from the asymptotic limit of the $\gamma^{\ast}\gamma-\eta^{\prime}$ transition form factor, we obtain $R_{h_{c}}=30.3\%$ in consistent with $R_{h_{c}}^{exp}=(30.7\pm11.3\pm8.7)\%$. As a cross-check, the mixing angle $\phi=33.8^{\circ}\pm2.5^{\circ}$ is extracted by employing the ratio $R_{h_{c}}$, and a brief discussion on the difference in the determinations of $\phi$ is given.
[ { "created": "Thu, 12 Mar 2020 06:05:09 GMT", "version": "v1" }, { "created": "Tue, 16 Feb 2021 06:20:59 GMT", "version": "v2" } ]
2021-06-09
[ [ "He", "Jun-Kang", "" ], [ "Fan", "Chao-Jie", "" ] ]
The $P$-wave charmonium decays $h_{c}\rightarrow\gamma\eta^{(\prime)}$ are revisited by taking into account relativistic corrections. The decay amplitudes are derived in the Bethe-Salpeter formalism, in which the involved one-loop integrals are evaluated analytically. Intriguingly, from both the quark-antiquark content and the gluonic content of $\eta^{(\prime)}$, the relativistic corrections make significant contributions to the decay rates of $h_{c}\rightarrow\gamma\eta^{(\prime)}$. By comparison with the leading-order contributions from the quark-antiquark content (one-loop level), the ones from the gluonic content (tree level) are also important, which is compatible with the conclusion obtained without relativistic corrections. Usually, for $\eta$ production processes, the predicted branching ratios are sensitive to the angle of $\eta-\eta^{\prime}$ mixing. As an illustration, using the Feldmann-Kroll-Stech result about the mixing angle $\phi=39.3^{\circ}\pm1.0^{\circ}$ as input, we find that the predicted ratio $R_{h_{c}}=\mathcal{B}(h_{c}\rightarrow\gamma\eta)/\mathcal{B}(h_{c}\rightarrow\gamma\eta^{\prime})$ is much smaller than the experiment measurement. While, with $\phi=33.5^{\circ}\pm0.9^{\circ}$ extracted from the asymptotic limit of the $\gamma^{\ast}\gamma-\eta^{\prime}$ transition form factor, we obtain $R_{h_{c}}=30.3\%$ in consistent with $R_{h_{c}}^{exp}=(30.7\pm11.3\pm8.7)\%$. As a cross-check, the mixing angle $\phi=33.8^{\circ}\pm2.5^{\circ}$ is extracted by employing the ratio $R_{h_{c}}$, and a brief discussion on the difference in the determinations of $\phi$ is given.
hep-ph/9307366
Harada Masayasu
Masako Bando and Masayasu Harada
Axial Anomaly and Transition Form Factors
LaTeX, 14 pages + 4 figures, (figures are included as uuencoded files), KUNS-1210 HE(TH) 93/07
Phys.Rev. D49 (1994) 6096-6100
10.1103/PhysRevD.49.6096
null
hep-ph
null
We investigate the properties of the amplitude induced by the anomaly. In a relatively high energy region those amplitudes are constructed by the vector meson poles and the anomaly terms, in which the anomaly terms can be essentially evaluated by the triangle quark graph. We pay our attention to the anomaly term and make intensive analysis of the existing experimental data, i.e., the electromagnetic $\pi^0$ and $\omega$ transition form factors. Our result shows that it is essential to use the constituent quark mass instead of the current quark mass in evaluating the anomaly term from the triangle graph.
[ { "created": "Thu, 29 Jul 1993 16:48:57 GMT", "version": "v1" } ]
2009-10-22
[ [ "Bando", "Masako", "" ], [ "Harada", "Masayasu", "" ] ]
We investigate the properties of the amplitude induced by the anomaly. In a relatively high energy region those amplitudes are constructed by the vector meson poles and the anomaly terms, in which the anomaly terms can be essentially evaluated by the triangle quark graph. We pay our attention to the anomaly term and make intensive analysis of the existing experimental data, i.e., the electromagnetic $\pi^0$ and $\omega$ transition form factors. Our result shows that it is essential to use the constituent quark mass instead of the current quark mass in evaluating the anomaly term from the triangle graph.
hep-ph/0005120
Ingo Bojak
Ingo Bojak (Univ. Dortmund)
NLO QCD Corrections to the Polarized Photo- and Hadroproduction of Heavy Quarks
PhD thesis, LaTeX, 189 pages, 57 figures, for double-sided printing, other formats (one-sided, 2-on-1) at http://doom.physik.uni-dortmund.de/~bojak
null
null
DO-TH 2000/09
hep-ph
null
The complete details of our calculation of the NLO QCD corrections to heavy flavor photo- and hadroproduction with longitudinally polarized initial states are presented. The main motivation for investigating these processes is the determination of the polarized gluon density at the COMPASS and RHIC experiments, respectively, in the near future. All methods used in the computation are extensively documented, providing a self-contained introduction to this type of calculations. Some employed tools also may be of general interest, e.g., the series expansion of hypergeometric functions. The relevant parton level results are collected and plotted in the form of scaling functions. However, the simplification of the obtained gluon-gluon virtual contributions has not been completed yet. Thus NLO phenomenological predictions are only given in the case of photoproduction. The theoretical uncertainties of these predictions, in particular with respect to the heavy quark mass, are carefully considered. Also it is shown that transverse momentum cuts can considerably enhance the measured production asymmetries. Finally unpolarized heavy quark production is reviewed in order to derive conditions for a successful interpretation of future spin-dependent experimental data.
[ { "created": "Fri, 12 May 2000 10:50:16 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bojak", "Ingo", "", "Univ. Dortmund" ] ]
The complete details of our calculation of the NLO QCD corrections to heavy flavor photo- and hadroproduction with longitudinally polarized initial states are presented. The main motivation for investigating these processes is the determination of the polarized gluon density at the COMPASS and RHIC experiments, respectively, in the near future. All methods used in the computation are extensively documented, providing a self-contained introduction to this type of calculations. Some employed tools also may be of general interest, e.g., the series expansion of hypergeometric functions. The relevant parton level results are collected and plotted in the form of scaling functions. However, the simplification of the obtained gluon-gluon virtual contributions has not been completed yet. Thus NLO phenomenological predictions are only given in the case of photoproduction. The theoretical uncertainties of these predictions, in particular with respect to the heavy quark mass, are carefully considered. Also it is shown that transverse momentum cuts can considerably enhance the measured production asymmetries. Finally unpolarized heavy quark production is reviewed in order to derive conditions for a successful interpretation of future spin-dependent experimental data.
0705.3290
Asan Damanik
Asan Damanik, Mirza Satriawan, Muslim, Pramudita Anggraita
Neutrino Mass Matrix from Seesaw Mechanism Subjected to Texture Zero and Invariant Under a Cyclic Permutation
8 pages, no figure,typos corrected,three references added
null
null
null
hep-ph
null
We evaluate the predictive power of the neutrino mass matrices arising from seesaw mechanism subjected to texture zero and satisfying a cyclic permutation invariant. We found that only two from eight possible patterns of the neutrino mass matrices are invariant under a cyclic permutation. The two resulted neutrino mass matrices which are invariant under a cyclic permutation can be used qualitatively to explain the neutrino mixing phenomena for solar neutrino and to derive the mixing angle that agress with the experimental data.
[ { "created": "Wed, 23 May 2007 05:10:48 GMT", "version": "v1" }, { "created": "Thu, 24 May 2007 11:44:19 GMT", "version": "v2" }, { "created": "Fri, 8 Jun 2007 07:16:08 GMT", "version": "v3" }, { "created": "Tue, 12 Jun 2007 05:32:11 GMT", "version": "v4" } ]
2007-06-12
[ [ "Damanik", "Asan", "" ], [ "Satriawan", "Mirza", "" ], [ "Muslim", "", "" ], [ "Anggraita", "Pramudita", "" ] ]
We evaluate the predictive power of the neutrino mass matrices arising from seesaw mechanism subjected to texture zero and satisfying a cyclic permutation invariant. We found that only two from eight possible patterns of the neutrino mass matrices are invariant under a cyclic permutation. The two resulted neutrino mass matrices which are invariant under a cyclic permutation can be used qualitatively to explain the neutrino mixing phenomena for solar neutrino and to derive the mixing angle that agress with the experimental data.
hep-ph/9511371
Colin Froggatt
C. D. Froggatt and H. B. Nielsen
Standard Model Criticality Prediction: Top mass 173 +/- 5 GeV and Higgs mass 135 +/- 9 GeV
13 pages LaTeX with epsf, 1 page of figures appended as a uuencoded file; to appear in Physics Letters B
Phys.Lett. B368 (1996) 96-102
10.1016/0370-2693(95)01480-2
GUTPA/95/10/1
hep-ph
null
Imposing the constraint that the Standard Model effective Higgs potential should have two degenerate minima ( vacua), one of which should be - order of magnitudewise - at the Planck scale, leads to the top mass being 173 +/- 5 GeV and the Higgs mass 135 +/- 9 GeV. This requirement of the degeneracy of different phases is a special case of what we call the multiple point criticality principle. In the present work we use the Standard Model all the way to the Planck scale, and do not introduce supersymmetry or any extension of the Standard Model gauge group. A possible model to explain the multiple point criticality principle is lack of locality fundamentally.
[ { "created": "Mon, 20 Nov 1995 12:51:07 GMT", "version": "v1" } ]
2009-10-28
[ [ "Froggatt", "C. D.", "" ], [ "Nielsen", "H. B.", "" ] ]
Imposing the constraint that the Standard Model effective Higgs potential should have two degenerate minima ( vacua), one of which should be - order of magnitudewise - at the Planck scale, leads to the top mass being 173 +/- 5 GeV and the Higgs mass 135 +/- 9 GeV. This requirement of the degeneracy of different phases is a special case of what we call the multiple point criticality principle. In the present work we use the Standard Model all the way to the Planck scale, and do not introduce supersymmetry or any extension of the Standard Model gauge group. A possible model to explain the multiple point criticality principle is lack of locality fundamentally.
hep-ph/9501373
Pieter Rijken
P.J. Rijken and W.L. van Neerven
Heavy flavor contributions to the Drell-Yan cross section
30 pages, 7 PostScript figures, uses epsf and mcite (is included).
Phys.Rev.D52:149-161,1995
10.1103/PhysRevD.52.149
INLO-PUB-1/95
hep-ph
null
We investigate the effect of heavy flavor contributions to vector boson ($V$ = $\gamma$, $Z$, $W$) production which is described by the Drell-Yan mechanism. All reactions with bottom and top quarks ($Q_i$ = $b$, $t$) in the final state, like $q_1 + \bar{q}_2\rightarrow V + Q_1 + \bar{Q}_2$ and $g + g\rightarrow V + Q_1 + \bar{Q}_2$, are considered. This study also includes the virtual contributions containing heavy flavor loops which were not taken into account earlier in the literature. Our analysis reveals that the above corrections to the Drell-Yan cross section are very small. Only at energies characteristic for the LHC they are of the same order of magnitude as the order \alphastwo~QCD contributions due to light quark and gluon subprocesses calculated earlier in the literature.
[ { "created": "Wed, 25 Jan 1995 13:34:03 GMT", "version": "v1" } ]
2010-11-01
[ [ "Rijken", "P. J.", "" ], [ "van Neerven", "W. L.", "" ] ]
We investigate the effect of heavy flavor contributions to vector boson ($V$ = $\gamma$, $Z$, $W$) production which is described by the Drell-Yan mechanism. All reactions with bottom and top quarks ($Q_i$ = $b$, $t$) in the final state, like $q_1 + \bar{q}_2\rightarrow V + Q_1 + \bar{Q}_2$ and $g + g\rightarrow V + Q_1 + \bar{Q}_2$, are considered. This study also includes the virtual contributions containing heavy flavor loops which were not taken into account earlier in the literature. Our analysis reveals that the above corrections to the Drell-Yan cross section are very small. Only at energies characteristic for the LHC they are of the same order of magnitude as the order \alphastwo~QCD contributions due to light quark and gluon subprocesses calculated earlier in the literature.
2309.03711
Manjit Kaur Dr.
Soumya Sarkar and R. Aggarwal and M. Kaur
Search for nonextensivity in electron-proton interactions at $\sqrt{s}$ = 300 GeV
13 pages,11 Figures, 8 Tables
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Study of canonical entropy in electron-proton interactions at $\sqrt{s}$ = 300 GeV is presented. The precision data collected by the H1 experiment at the HERA in different ranges of invariant hadronic mass $W$ and the squared four-momentum exchange $Q^{2}$ in $ep$ interactions have been analyzed in the ensemble theory approach. The canonical partition function relates to the multiplicity distribution which is often studied in collider experiments. We use the canonical ensemble partition function to explore the dynamics of hadron production in $ep$ interactions by devising different methods to find the entropic parameter and the collision temperature. The inverse slope of the transverse momentum spectrum of produced hadrons also relates to the temperature. In the recent past, the CMS, ATLAS and ALICE experiments at the LHC have studied the charged hadron transverse momentum and particle distributions in proton-proton and proton-nucleus interactions by using the Tsallis function within this approach. A detailed investigation into the role of the system volume and relation amongst different dynamical parameters reveals interesting results.
[ { "created": "Thu, 7 Sep 2023 13:38:54 GMT", "version": "v1" }, { "created": "Tue, 27 Feb 2024 17:56:02 GMT", "version": "v2" } ]
2024-02-28
[ [ "Sarkar", "Soumya", "" ], [ "Aggarwal", "R.", "" ], [ "Kaur", "M.", "" ] ]
Study of canonical entropy in electron-proton interactions at $\sqrt{s}$ = 300 GeV is presented. The precision data collected by the H1 experiment at the HERA in different ranges of invariant hadronic mass $W$ and the squared four-momentum exchange $Q^{2}$ in $ep$ interactions have been analyzed in the ensemble theory approach. The canonical partition function relates to the multiplicity distribution which is often studied in collider experiments. We use the canonical ensemble partition function to explore the dynamics of hadron production in $ep$ interactions by devising different methods to find the entropic parameter and the collision temperature. The inverse slope of the transverse momentum spectrum of produced hadrons also relates to the temperature. In the recent past, the CMS, ATLAS and ALICE experiments at the LHC have studied the charged hadron transverse momentum and particle distributions in proton-proton and proton-nucleus interactions by using the Tsallis function within this approach. A detailed investigation into the role of the system volume and relation amongst different dynamical parameters reveals interesting results.
hep-ph/9212292
null
Reinhard Oehme
On the Analytic Structure of Hadronic Amplitudes in QCD
14 pages, Latex, EFI 92-54
null
null
null
hep-ph
null
Analytic properties of hadronic amplitudes are discussed within the framework of QCD as formulated on the basis of the BRST algebra. Local, composite fields are introduced for hadrons. Given confinement, it is shown that hadronic amplitudes have no thresholds or structure singularities (anomalous thresholds) which are directly related to the underlying quark-gluon structure. In contrast, general amplitudes of QCD must have singularities in channels with non-zero color quantum number, which can be related to unphysical states.
[ { "created": "Mon, 21 Dec 1992 16:25:25 GMT", "version": "v1" } ]
2007-05-23
[ [ "Oehme", "Reinhard", "" ] ]
Analytic properties of hadronic amplitudes are discussed within the framework of QCD as formulated on the basis of the BRST algebra. Local, composite fields are introduced for hadrons. Given confinement, it is shown that hadronic amplitudes have no thresholds or structure singularities (anomalous thresholds) which are directly related to the underlying quark-gluon structure. In contrast, general amplitudes of QCD must have singularities in channels with non-zero color quantum number, which can be related to unphysical states.
hep-ph/9506272
null
W. Grimus (U. Wien), M. N. Rebelo (U. Wien and CFIF-IST, Lisbon)
Automorphisms in Gauge Theories and the Definition of CP and P
77 pages (when compiled with 4TEX), one figure included, all in Latex. It is necessary to compile the paper three times so that the Table of Contents will be generated with the correct page numbers
Phys.Rept.281:239-308,1997
10.1016/S0370-1573(96)00030-0
UWThPh-1995-7
hep-ph
null
We study the possibilities to define CP and parity in general gauge theories by utilizing the intimate connection of these discrete symmetries with the group of automorphisms of the gauge Lie algebra. Special emphasis is put on the scalar gauge interactions and the CP invariance of the Yukawa couplings.
[ { "created": "Thu, 8 Jun 1995 16:36:00 GMT", "version": "v1" } ]
2009-05-29
[ [ "Grimus", "W.", "", "U. Wien" ], [ "Rebelo", "M. N.", "", "U. Wien and CFIF-IST, Lisbon" ] ]
We study the possibilities to define CP and parity in general gauge theories by utilizing the intimate connection of these discrete symmetries with the group of automorphisms of the gauge Lie algebra. Special emphasis is put on the scalar gauge interactions and the CP invariance of the Yukawa couplings.
hep-ph/0308172
Susumu Koretune
S.Koretune
Symmetry restoration of the soft pion corrections for the light sea quark distributions in the small $x$ region
22 pages including 4 eps figures, ReVTeX, to appear in Phys. Rev. D
Phys.Rev. D68 (2003) 054011
10.1103/PhysRevD.68.054011
null
hep-ph
null
The soft pion correction at high energy may play a crucial role in non-perturbative parts of sea quark distributions. In this paper, we show that, while the soft pion correction for the strange sea qaurk distribution is suppressed in the large and the medium $x$ region compared with that for the up and the down sea quark one, it can become large and SU(3) flavor symmetric in the very small $x$ region. This gives us a good reason for the symmetry restoration of light sea quark distributions required by the mean charge sum rule for the light sea quarks. Then, by estimating this sum rule with the help of the results obtained by the soft pion correction, it is argued that there is a large symmetry restoration of the strange sea quark in the region from $x=10^{-2}$ to $10^{-6}$ at $Q^2\sim 1$ GeV.
[ { "created": "Mon, 18 Aug 2003 01:07:00 GMT", "version": "v1" } ]
2009-11-10
[ [ "Koretune", "S.", "" ] ]
The soft pion correction at high energy may play a crucial role in non-perturbative parts of sea quark distributions. In this paper, we show that, while the soft pion correction for the strange sea qaurk distribution is suppressed in the large and the medium $x$ region compared with that for the up and the down sea quark one, it can become large and SU(3) flavor symmetric in the very small $x$ region. This gives us a good reason for the symmetry restoration of light sea quark distributions required by the mean charge sum rule for the light sea quarks. Then, by estimating this sum rule with the help of the results obtained by the soft pion correction, it is argued that there is a large symmetry restoration of the strange sea quark in the region from $x=10^{-2}$ to $10^{-6}$ at $Q^2\sim 1$ GeV.
2111.02319
Bogdan Malaescu
Thomas Gehrmann and Bogdan Malaescu
Precision QCD Physics at the LHC
19 pages, 8 figures, version accepted for publication in Annual Review of Nuclear and Particle Science
null
10.1146/annurev-nucl-101920-014923
ZU-TH 53/21
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
This review describes the current status of precision QCD studies at the LHC. We introduce the main experimental and theoretical methods, discussing also their cross-stimulated developments and recent advances. The different types of QCD observables that are measured at the LHC, including cross-sections, event- and jet-level properties, for various final states, are summarised. Their relation to fundamental QCD dynamics and their impact on Standard Model parameter determinations are discussed on specific examples. The impact of QCD-related observables on direct and indirect searches for rare processes within and new physics beyond the Standard Model is outlined.
[ { "created": "Wed, 3 Nov 2021 16:12:50 GMT", "version": "v1" }, { "created": "Wed, 18 May 2022 20:38:29 GMT", "version": "v2" } ]
2022-10-12
[ [ "Gehrmann", "Thomas", "" ], [ "Malaescu", "Bogdan", "" ] ]
This review describes the current status of precision QCD studies at the LHC. We introduce the main experimental and theoretical methods, discussing also their cross-stimulated developments and recent advances. The different types of QCD observables that are measured at the LHC, including cross-sections, event- and jet-level properties, for various final states, are summarised. Their relation to fundamental QCD dynamics and their impact on Standard Model parameter determinations are discussed on specific examples. The impact of QCD-related observables on direct and indirect searches for rare processes within and new physics beyond the Standard Model is outlined.
1408.2433
Riccardo Giachetti
A. Barducci, R. Giachetti, E. Sorace
Relativistic two fermion treatment of hyperfine transitions
8 pages
null
10.1088/0953-4075/48/8/085002
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A system of two fermions with different masses and interacting by the Coulomb potential is presented in a completely covariant framework. The spin-spin interaction, including the anomalous magnetic moments of the two fermions, is added by means of a Breit term. We solve the resulting fourth order differential system by evaluating the spectrum and the eigenfunctions. The interaction vertex with an external electromagnetic field is then determined. The relativistic eigenfunctions are used to study the photon emission from a hyperfine transition and are checked for the calculation of the Lamb shift due to the electron vacuum polarization in the muonic Hydrogen.
[ { "created": "Mon, 11 Aug 2014 15:11:26 GMT", "version": "v1" } ]
2015-06-22
[ [ "Barducci", "A.", "" ], [ "Giachetti", "R.", "" ], [ "Sorace", "E.", "" ] ]
A system of two fermions with different masses and interacting by the Coulomb potential is presented in a completely covariant framework. The spin-spin interaction, including the anomalous magnetic moments of the two fermions, is added by means of a Breit term. We solve the resulting fourth order differential system by evaluating the spectrum and the eigenfunctions. The interaction vertex with an external electromagnetic field is then determined. The relativistic eigenfunctions are used to study the photon emission from a hyperfine transition and are checked for the calculation of the Lamb shift due to the electron vacuum polarization in the muonic Hydrogen.
hep-ph/9402313
Gye Park
T. K. Kuo and Gye T. Park
Precision Electroweak Tests on the $Sp(6)_L \times U(1)_Y$ Model
14 pages+2 figures(not included), PURD-TH-93-13, to appear in Phys. Rev. D(figures available upon request by regular mail)
Phys.Rev. D50 (1994) 3508-3512
10.1103/PhysRevD.50.3508
null
hep-ph
null
We perform precision electroweak tests on the $Sp(6)_L \times U(1)_Y$ model. The purpose of the analysis is to delineate the model parameters such as the mixing angles of the extra gauge bosons present in this model. We find that the model is already constrained considerably by the present LEP data.
[ { "created": "Fri, 18 Feb 1994 02:56:42 GMT", "version": "v1" } ]
2009-10-28
[ [ "Kuo", "T. K.", "" ], [ "Park", "Gye T.", "" ] ]
We perform precision electroweak tests on the $Sp(6)_L \times U(1)_Y$ model. The purpose of the analysis is to delineate the model parameters such as the mixing angles of the extra gauge bosons present in this model. We find that the model is already constrained considerably by the present LEP data.
1910.09384
Qingjun Jin
Qingjun Jin, Gang Yang
Two-Loop QCD Corrections to the Higgs plus three-parton amplitudes with Top Mass Correction
41 pages, 11 figures
null
10.1007/JHEP02(2020)169
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We obtain the two-loop QCD corrections to the Higgs plus three-parton amplitudes with dimension-seven operators in Higgs effective field theory. This provides the two-loop S-matrix elements for Higgs plus one-jet production at the LHC with top-mass correction. We apply efficient unitarity plus IBP methods which are described in detail. We also study the color decomposition of the fermion cuts and find a connection between fundamental and adjoint representations which can be used to reduce non-planar to planar unitarity cuts in the Higgs to three-gluon amplitudes. We obtain final results in simple analytic form which exhibits intriguing hidden structures. The principle of maximal transcendentality is found to be satisfied for all results. The lower transcendentality parts also contain universal building blocks and can be written in compact analytic form, suggesting further hidden structures.
[ { "created": "Mon, 21 Oct 2019 13:59:05 GMT", "version": "v1" }, { "created": "Thu, 12 Mar 2020 06:58:59 GMT", "version": "v2" } ]
2020-03-18
[ [ "Jin", "Qingjun", "" ], [ "Yang", "Gang", "" ] ]
We obtain the two-loop QCD corrections to the Higgs plus three-parton amplitudes with dimension-seven operators in Higgs effective field theory. This provides the two-loop S-matrix elements for Higgs plus one-jet production at the LHC with top-mass correction. We apply efficient unitarity plus IBP methods which are described in detail. We also study the color decomposition of the fermion cuts and find a connection between fundamental and adjoint representations which can be used to reduce non-planar to planar unitarity cuts in the Higgs to three-gluon amplitudes. We obtain final results in simple analytic form which exhibits intriguing hidden structures. The principle of maximal transcendentality is found to be satisfied for all results. The lower transcendentality parts also contain universal building blocks and can be written in compact analytic form, suggesting further hidden structures.
1406.5811
Premomoy Ghosh
Premomoy Ghosh, Sanjib Muhuri
Do we see change of phase in proton-proton collisions at the Large Hadron Collider?
5 pages 3 figures
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
High multiplicity events in proton-proton collisions at the Large Hadron Collider exhibit features resembling those found in relativistic nuclear collisions, indicating formation of medium of similar nature. Analyzing the proton-proton collision data, we find a clear signal of occurrence of change in phase between thermalized partonic matter and hadronic one as has been predicted by the lattice quantum chromodynamics.
[ { "created": "Mon, 23 Jun 2014 05:43:44 GMT", "version": "v1" }, { "created": "Fri, 21 Nov 2014 18:38:38 GMT", "version": "v2" } ]
2014-11-24
[ [ "Ghosh", "Premomoy", "" ], [ "Muhuri", "Sanjib", "" ] ]
High multiplicity events in proton-proton collisions at the Large Hadron Collider exhibit features resembling those found in relativistic nuclear collisions, indicating formation of medium of similar nature. Analyzing the proton-proton collision data, we find a clear signal of occurrence of change in phase between thermalized partonic matter and hadronic one as has been predicted by the lattice quantum chromodynamics.
hep-ph/0311053
Wanda Maria Alberico
W.M. Alberico, S.M. Bilenky and C. Maieron
Looking for strangeness with neutrino-nucleon scattering
6 pages, 1 figure, contribution to : "NuFact 03", 5th International Workshop on Neutrino Factories & Superbeams, Columbia University, New York, 5-11 June 2003
null
10.1063/1.1818432
null
hep-ph
null
The possibility to determine the axial strange form factor of the nucleon from elastic neutrino-nucleon scattering experiments is studied. The existing experimental information is shortly mentioned and several observables which could be measured in the near future at new neutrino facilities are discussed.
[ { "created": "Tue, 4 Nov 2003 19:23:20 GMT", "version": "v1" } ]
2009-11-10
[ [ "Alberico", "W. M.", "" ], [ "Bilenky", "S. M.", "" ], [ "Maieron", "C.", "" ] ]
The possibility to determine the axial strange form factor of the nucleon from elastic neutrino-nucleon scattering experiments is studied. The existing experimental information is shortly mentioned and several observables which could be measured in the near future at new neutrino facilities are discussed.
hep-ph/9408315
null
Valerie Ben-Hamo and Yosef Nir
Implications of Horizontal Symmetries on Baryon Number Violation in Supersymmetric Models
11 pages, WIS-94/34/Aug-PH
Phys.Lett.B339:77-82,1994
10.1016/0370-2693(94)91135-5
null
hep-ph
null
The smallness of the quark and lepton parameters and the hierarchy between them could be the result of selection rules due to a horizontal symmetry broken by a small parameter. The same selection rules apply to baryon number violating terms. Consequently, the problem of baryon number violation in Supersymmetry may be solved naturally, without invoking any especially-designed extra symmetry. This mechanism is efficient enough even for low-scale flavor physics. Proton decay is likely to be dominated by the modes $K^+\bar\nu_i$ or $K^0\mu^+(e^+)$, and may proceed at observable rates.
[ { "created": "Thu, 18 Aug 1994 07:00:50 GMT", "version": "v1" } ]
2011-04-08
[ [ "Ben-Hamo", "Valerie", "" ], [ "Nir", "Yosef", "" ] ]
The smallness of the quark and lepton parameters and the hierarchy between them could be the result of selection rules due to a horizontal symmetry broken by a small parameter. The same selection rules apply to baryon number violating terms. Consequently, the problem of baryon number violation in Supersymmetry may be solved naturally, without invoking any especially-designed extra symmetry. This mechanism is efficient enough even for low-scale flavor physics. Proton decay is likely to be dominated by the modes $K^+\bar\nu_i$ or $K^0\mu^+(e^+)$, and may proceed at observable rates.
hep-ph/0001045
Alejandro Ayala
Alejandro Ayala, Sarira Sahu (ICN-UNAM) and Mauro Napsuciale (IF-UG)
Pion dispersion relation at finite temperature in the linear sigma model from chiral Ward identities
9 pages, 4 figures uses revtex and epsfig. Expanded discussion, new references added, typos corrected. To appear in Phys. Lett. B
Phys.Lett.B479:156-162,2000
10.1016/S0370-2693(00)00298-7
null
hep-ph nucl-th
null
We develop one-loop effective vertices and propagators in the linear sigma model at finite temperature satisfying the chiral Ward identities. We use these in turn to compute the pion dispersion relation in a pion medium for small momentum and temperatures on the order of the pion mass at next to leading order in the parameter m_pi^2/4pi^2f_pi^2 and to zeroth order in the parameter (m_pi/m_sigma)^2. We show that this expansion reproduces the result obtained from chiral perturbation theory at leading order. The main effect is a perturbative, temperature-dependent increase of the pion mass. We find no qualitative changes in the pion dispersion curve with respect to the leading order behavior in this kinematical regime.
[ { "created": "Thu, 6 Jan 2000 01:10:56 GMT", "version": "v1" }, { "created": "Thu, 2 Mar 2000 00:51:45 GMT", "version": "v2" } ]
2009-09-24
[ [ "Ayala", "Alejandro", "", "ICN-UNAM" ], [ "Sahu", "Sarira", "", "ICN-UNAM" ], [ "Napsuciale", "Mauro", "", "IF-UG" ] ]
We develop one-loop effective vertices and propagators in the linear sigma model at finite temperature satisfying the chiral Ward identities. We use these in turn to compute the pion dispersion relation in a pion medium for small momentum and temperatures on the order of the pion mass at next to leading order in the parameter m_pi^2/4pi^2f_pi^2 and to zeroth order in the parameter (m_pi/m_sigma)^2. We show that this expansion reproduces the result obtained from chiral perturbation theory at leading order. The main effect is a perturbative, temperature-dependent increase of the pion mass. We find no qualitative changes in the pion dispersion curve with respect to the leading order behavior in this kinematical regime.
hep-ph/9502331
null
Eric Sather (SLAC) and Witold Skiba (MIT)
Constraining the Strongly-Coupled Standard Model Including a W' Isotriplet
20 pages, LaTeX, 4 uuencoded postscript figures
Phys.Rev. D53 (1996) 527-536
10.1103/PhysRevD.53.527
SLAC-PUB-6657, MIT-CTP-2409, NSF-ITP-95-09
hep-ph
null
We consider the Strongly-Coupled Standard Model (Abbott-Farhi model) including an isotriplet of W' vector bosons. First we calculate the corrections to the low-energy theory, which can be effectively summarized in terms of the parameters S, T and U. Then we use high- precision electroweak measurements to constrain the mass and couplings of the W'. The W' couplings are restricted to be unnaturally small, and we conclude that this model is no longer compelling as a theory of the electroweak interactions.
[ { "created": "Thu, 16 Feb 1995 22:03:36 GMT", "version": "v1" } ]
2016-09-01
[ [ "Sather", "Eric", "", "SLAC" ], [ "Skiba", "Witold", "", "MIT" ] ]
We consider the Strongly-Coupled Standard Model (Abbott-Farhi model) including an isotriplet of W' vector bosons. First we calculate the corrections to the low-energy theory, which can be effectively summarized in terms of the parameters S, T and U. Then we use high- precision electroweak measurements to constrain the mass and couplings of the W'. The W' couplings are restricted to be unnaturally small, and we conclude that this model is no longer compelling as a theory of the electroweak interactions.
2301.13123
Pranava Teja Surukuchi
Yoshi Fujikake, Bryce Littlejohn, Ohana B. Rodrigues, Pranava Teja Surukuchi
Exploring Current Constraints on Antineutrino Production by $^{241}$Pu and Paths Towards the Precision Reactor Flux Era
13 page, 6 figures
null
10.1103/PhysRevD.107.092010
null
hep-ph nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
By performing global fits to inverse beta decay (IBD) yield measurements from existing neutrino experiments based at highly $^{235}$U enriched reactor cores and conventional low-enriched cores, we explore current direct bounds on neutrino production by the sub-dominant fission isotope $^{241}$Pu. For this nuclide, we determine an IBD yield of $\sigma_{241}$ = 8.16 $\pm$ 3.47 cm$^2$/fission, a value (135 $\pm$ 58)% that of current beta conversion models. This constraint is shown to derive from the non-linear relationship between burn-in of $^{241}$Pu and $^{239}$Pu in conventional reactor fuel. By considering new hypothetical neutrino measurements at high-enriched, low-enriched, mixed-oxide, and fast reactor facilities, we investigate the feasible limits of future knowledge of IBD yields for $^{235}$U, $^{238}$U, $^{239}$Pu, $^{241}$Pu, and $^{240}$Pu. We find that the first direct measurement of the $^{240}$Pu IBD yield can be performed at plutonium-burning fast reactors, while a suite of correlated measurements at multiple reactor types can achieve precision in direct $^{238}$U, $^{239}$Pu, and $^{241}$Pu yield knowledge that meets or exceeds that of current theoretical predictions.
[ { "created": "Mon, 30 Jan 2023 18:01:08 GMT", "version": "v1" } ]
2023-06-07
[ [ "Fujikake", "Yoshi", "" ], [ "Littlejohn", "Bryce", "" ], [ "Rodrigues", "Ohana B.", "" ], [ "Surukuchi", "Pranava Teja", "" ] ]
By performing global fits to inverse beta decay (IBD) yield measurements from existing neutrino experiments based at highly $^{235}$U enriched reactor cores and conventional low-enriched cores, we explore current direct bounds on neutrino production by the sub-dominant fission isotope $^{241}$Pu. For this nuclide, we determine an IBD yield of $\sigma_{241}$ = 8.16 $\pm$ 3.47 cm$^2$/fission, a value (135 $\pm$ 58)% that of current beta conversion models. This constraint is shown to derive from the non-linear relationship between burn-in of $^{241}$Pu and $^{239}$Pu in conventional reactor fuel. By considering new hypothetical neutrino measurements at high-enriched, low-enriched, mixed-oxide, and fast reactor facilities, we investigate the feasible limits of future knowledge of IBD yields for $^{235}$U, $^{238}$U, $^{239}$Pu, $^{241}$Pu, and $^{240}$Pu. We find that the first direct measurement of the $^{240}$Pu IBD yield can be performed at plutonium-burning fast reactors, while a suite of correlated measurements at multiple reactor types can achieve precision in direct $^{238}$U, $^{239}$Pu, and $^{241}$Pu yield knowledge that meets or exceeds that of current theoretical predictions.
2004.02332
Zhi-Wei Wang
Wei-Chih Huang, Francesco Sannino, Zhi-Wei Wang
Gravitational Waves from Pati-Salam Dynamics
12 pages, 6 figures
null
10.1103/PhysRevD.102.095025
CP3-Origins-2020-05 DNRF90
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that it is possible to use gravitational wave detectors to observe the occurrence of a first order phase transition in Pati-Salam extensions of the Standard Model. We show that the peak frequency of the expected gravitational wave signals ranges within $0.1-10$ Hz. We find amusing that the next generation of gravity waves detectors are able to explore time honoured extensions of the Standard Model occurring at energy scales inaccessible by present and future particle physics accelerators.
[ { "created": "Sun, 5 Apr 2020 22:12:02 GMT", "version": "v1" } ]
2020-12-30
[ [ "Huang", "Wei-Chih", "" ], [ "Sannino", "Francesco", "" ], [ "Wang", "Zhi-Wei", "" ] ]
We show that it is possible to use gravitational wave detectors to observe the occurrence of a first order phase transition in Pati-Salam extensions of the Standard Model. We show that the peak frequency of the expected gravitational wave signals ranges within $0.1-10$ Hz. We find amusing that the next generation of gravity waves detectors are able to explore time honoured extensions of the Standard Model occurring at energy scales inaccessible by present and future particle physics accelerators.
1605.08520
Mariko Kikuchi
Shinya Kanemura, Mariko Kikuchi, Kodai Sakurai
Testing the dark matter scenario in the inert doublet model by future precision measurements of the Higgs boson couplings
27 pages, 7 figures
Phys. Rev. D 94, 115011 (2016)
10.1103/PhysRevD.94.115011
UT-HET 114
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate radiative corrections to the Higgs boson couplings in the inert doublet model, in which the lightest component of the $Z_2^{}$ odd scalar doublet field can be a dark matter candidate. The one-loop contributions to the $hVV$, $hff$ and $hhh$ couplings are calculated in the on-shell scheme, where $h$ is the Higgs boson with the mass 125 GeV, $V$ represents a weak gauge boson and $f$ is a fermion. We investigate how the one-loop corrected Higgs boson couplings can be deviated from the predictions in the standard model under the constraints from perturbative unitarity and vacuum stability in the scenario where the model can explain current dark matter data. When the mass of the dark matter is slightly above a half of the Higgs boson mass, it would be difficult to test the model by the direct search experiments for dark matter. We find that in such a case the model can be tested at future collider experiments by either the direct search of heavier inert particles or precision measurements of the Higgs boson couplings.
[ { "created": "Fri, 27 May 2016 07:14:53 GMT", "version": "v1" } ]
2016-12-14
[ [ "Kanemura", "Shinya", "" ], [ "Kikuchi", "Mariko", "" ], [ "Sakurai", "Kodai", "" ] ]
We evaluate radiative corrections to the Higgs boson couplings in the inert doublet model, in which the lightest component of the $Z_2^{}$ odd scalar doublet field can be a dark matter candidate. The one-loop contributions to the $hVV$, $hff$ and $hhh$ couplings are calculated in the on-shell scheme, where $h$ is the Higgs boson with the mass 125 GeV, $V$ represents a weak gauge boson and $f$ is a fermion. We investigate how the one-loop corrected Higgs boson couplings can be deviated from the predictions in the standard model under the constraints from perturbative unitarity and vacuum stability in the scenario where the model can explain current dark matter data. When the mass of the dark matter is slightly above a half of the Higgs boson mass, it would be difficult to test the model by the direct search experiments for dark matter. We find that in such a case the model can be tested at future collider experiments by either the direct search of heavier inert particles or precision measurements of the Higgs boson couplings.
hep-ph/0412027
Alexander Krutov
A.F. Krutov (Samara State University), V.E. Troitsky (D.V. Skobeltsyn Institute of Nuclear Physics, Moscow State University)
Form Factors of Composite Systems by Generalized Wigner-Eckart Theorem for Poincar\'e group
Submitted to Theor. Math. Phys
Theor. and Math. Phys, 2005, 143:2, 704 (in Russian: Teor. Mat. Fiz.. 143: (2005) 258)
10.1007/s11232-005-0100-3
null
hep-ph
null
The relativistic approach to electroweak properties of two-particle composite systems developed previously is generalized here to the case of nonzero spin. This approach is based on the instant form of relativistic Hamiltonian dynamics. A special mathematical technique is used for the parametrization of matrix elements of electroweak current operators in terms of form factors. The parametrization is a realization of the generalized Wigner--Eckart theorem on the Poincar\'e group, form factors are corresponding reduced matrix elements and they have the sense of distributions (generalized functions). The electroweak current matrix element satisfies the relativistic covariance conditions and in the case of electromagnetic current it also automatically satisfies the conservation law.
[ { "created": "Thu, 2 Dec 2004 09:07:40 GMT", "version": "v1" } ]
2013-11-14
[ [ "Krutov", "A. F.", "", "Samara State University" ], [ "Troitsky", "V. E.", "", "D.V. Skobeltsyn\n Institute of Nuclear Physics, Moscow State University" ] ]
The relativistic approach to electroweak properties of two-particle composite systems developed previously is generalized here to the case of nonzero spin. This approach is based on the instant form of relativistic Hamiltonian dynamics. A special mathematical technique is used for the parametrization of matrix elements of electroweak current operators in terms of form factors. The parametrization is a realization of the generalized Wigner--Eckart theorem on the Poincar\'e group, form factors are corresponding reduced matrix elements and they have the sense of distributions (generalized functions). The electroweak current matrix element satisfies the relativistic covariance conditions and in the case of electromagnetic current it also automatically satisfies the conservation law.
2209.12520
Jason Aebischer
Benjamin Grinstein and Jason Aebischer
Lifetime of the $B^+_c$ meson in relation to flavour anomalies
5 pages, contribution to the proceedings of "The Tenth Annual Conference on Large Hadron Collider Physics" (LHCP2022). arXiv admin note: substantial text overlap with arXiv:2204.06225
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Standard Model decay rate of the $B_c$ meson is discussed together with a novel approach that uses experimental data in combination with an operator product expansion. In the new method differences of $B,\,D$ and $B_c$ meson decay rates are considered for which the free-quark contributions drop out, leading to a reduction of the theory prediction.
[ { "created": "Mon, 26 Sep 2022 08:55:42 GMT", "version": "v1" } ]
2022-09-27
[ [ "Grinstein", "Benjamin", "" ], [ "Aebischer", "Jason", "" ] ]
The Standard Model decay rate of the $B_c$ meson is discussed together with a novel approach that uses experimental data in combination with an operator product expansion. In the new method differences of $B,\,D$ and $B_c$ meson decay rates are considered for which the free-quark contributions drop out, leading to a reduction of the theory prediction.
2305.13666
Anthony Thomas Prof
Wanli Xing, Xuan-Gong Wang, Anthony W. Thomas
Electromagnetic form factors for nucleons in short-range correlations
6 pages, 6 figures, 2 tables
null
null
ADP-23-13/T1222
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent experimental studies have led to the suggestion that short-range correlations may be a major contributor to the nuclear EMC effect. This hypothesis requires that the structure function for nucleons involved in short-range correlations should be heavily suppressed compared to that of a free nucleon. Based on calculations performed within an AdS/QCD motivated, light-front quark-diquark model, we find that this large suppression of the nucleon structure function leads to a strong suppression of the nucleon elastic form factors.
[ { "created": "Tue, 23 May 2023 04:20:01 GMT", "version": "v1" }, { "created": "Thu, 21 Mar 2024 01:41:12 GMT", "version": "v2" } ]
2024-03-22
[ [ "Xing", "Wanli", "" ], [ "Wang", "Xuan-Gong", "" ], [ "Thomas", "Anthony W.", "" ] ]
Recent experimental studies have led to the suggestion that short-range correlations may be a major contributor to the nuclear EMC effect. This hypothesis requires that the structure function for nucleons involved in short-range correlations should be heavily suppressed compared to that of a free nucleon. Based on calculations performed within an AdS/QCD motivated, light-front quark-diquark model, we find that this large suppression of the nucleon structure function leads to a strong suppression of the nucleon elastic form factors.
hep-ph/0703111
Magno Machado
M.V.T. Machado
High energy electroweak DVCS processes in neutrino-nucleon scattering
7 pages, 6 figures. Version to be published in Physical Review D
Phys.Rev.D75:093008,2007
10.1103/PhysRevD.75.093008
null
hep-ph
null
In this work we estimate the differential and total cross sections for the high energy deeply virtual Compton scattering in the weak sector. In the weak neutral sector one considers neutrino scattering off an unpolarized proton target through the exchange of Z0. We numerically compute the process Z* p --> \gamma p within the QCD color dipole formalism, which successfully describes the current high energy electromagnetic DVCS experimental data. We also discuss possible applications for the weak charged sector and perform predictions for scattering on nuclear targets.
[ { "created": "Sat, 10 Mar 2007 18:25:46 GMT", "version": "v1" }, { "created": "Tue, 8 May 2007 20:02:17 GMT", "version": "v2" } ]
2008-11-26
[ [ "Machado", "M. V. T.", "" ] ]
In this work we estimate the differential and total cross sections for the high energy deeply virtual Compton scattering in the weak sector. In the weak neutral sector one considers neutrino scattering off an unpolarized proton target through the exchange of Z0. We numerically compute the process Z* p --> \gamma p within the QCD color dipole formalism, which successfully describes the current high energy electromagnetic DVCS experimental data. We also discuss possible applications for the weak charged sector and perform predictions for scattering on nuclear targets.
hep-ph/0203100
A. I. Milstein
R.N. Lee, A.I. Milstein, M. Schumacher
Electric polarizabilities of proton and neutron and the relativistic center-of-mass coordinate
8 pages, LaTeX, conclusion extended
Phys.Lett. B541 (2002) 87-92
10.1016/S0370-2693(02)02226-8
null
hep-ph nucl-th
null
We argue that the relativistic correction $\delta{\bf R}_{c.m.}$ to the center-of-mass vector can lead to the approximate equality of the proton and neutron electric polarizabilities in the quark model. The explicit form of $\delta{\bf R}_{c.m.}$ depends only on the non-relativistic potential between quarks. In particular, this correction is the same for the potential generated by Lorentz-vector and -scalar interactions.
[ { "created": "Mon, 11 Mar 2002 05:50:47 GMT", "version": "v1" }, { "created": "Sat, 27 Apr 2002 05:06:42 GMT", "version": "v2" } ]
2009-11-07
[ [ "Lee", "R. N.", "" ], [ "Milstein", "A. I.", "" ], [ "Schumacher", "M.", "" ] ]
We argue that the relativistic correction $\delta{\bf R}_{c.m.}$ to the center-of-mass vector can lead to the approximate equality of the proton and neutron electric polarizabilities in the quark model. The explicit form of $\delta{\bf R}_{c.m.}$ depends only on the non-relativistic potential between quarks. In particular, this correction is the same for the potential generated by Lorentz-vector and -scalar interactions.
hep-ph/9801442
Stefano Frixione
S. Frixione (ETH)
Isolated photons in perturbative QCD
10 pages Latex
Phys.Lett. B429 (1998) 369-374
10.1016/S0370-2693(98)00454-7
ETH-TH/97-40
hep-ph
null
I present a definition of the cross section for the production of an isolated photon plus $n$ jets which only depends upon direct photon production, and it is independent of the parton-to-photon fragmentation contribution. This prescription, based on a modified cone approach which implements the isolation condition in a smooth way, treats in the same way quarks and gluons and can be directly applied to experimental data in hadron-hadron, photon-hadron and $\epem$ collisions. The case of several, isolated photons in the final state can also be dealt with in the very same way.
[ { "created": "Thu, 29 Jan 1998 17:34:49 GMT", "version": "v1" } ]
2009-10-31
[ [ "Frixione", "S.", "", "ETH" ] ]
I present a definition of the cross section for the production of an isolated photon plus $n$ jets which only depends upon direct photon production, and it is independent of the parton-to-photon fragmentation contribution. This prescription, based on a modified cone approach which implements the isolation condition in a smooth way, treats in the same way quarks and gluons and can be directly applied to experimental data in hadron-hadron, photon-hadron and $\epem$ collisions. The case of several, isolated photons in the final state can also be dealt with in the very same way.
2211.11992
Dan Zhu
Dan Zhu, Khai-Ming Wong, Guo-Quan Wong
Electroweak Monopole-antimonopole Pair in the Standard Model
null
null
null
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
We present the first numerical solution that corresponds to a pair of Cho-Maison monopole and antimonopole (MAP) in the SU(2)$\times$U(1) Weinberg-Salam (WS) theory. The monopoles are finitely separated, while each pole carries magnetic charge $\pm 4\pi/e$. The positive pole is situated in the upper hemisphere, whereas the negative pole is in the lower hemisphere. The Cho-Maison MAP was investigated for a range of Weinberg angle, $0.4675\leq\tan\theta_W\leq10$, and Higgs self-coupling, $0\leq\beta\leq1.7704$. Magnetic dipole moment ($\mu_m$) and pole separation ($d_z$) of the numerical solutions are calculated and analyzed. Total energy of the system, however, is infinite due to point singularities at the locations of monopoles.
[ { "created": "Tue, 22 Nov 2022 04:09:55 GMT", "version": "v1" }, { "created": "Thu, 7 Sep 2023 08:45:28 GMT", "version": "v2" }, { "created": "Wed, 13 Sep 2023 12:06:20 GMT", "version": "v3" }, { "created": "Mon, 11 Dec 2023 17:34:15 GMT", "version": "v4" } ]
2023-12-12
[ [ "Zhu", "Dan", "" ], [ "Wong", "Khai-Ming", "" ], [ "Wong", "Guo-Quan", "" ] ]
We present the first numerical solution that corresponds to a pair of Cho-Maison monopole and antimonopole (MAP) in the SU(2)$\times$U(1) Weinberg-Salam (WS) theory. The monopoles are finitely separated, while each pole carries magnetic charge $\pm 4\pi/e$. The positive pole is situated in the upper hemisphere, whereas the negative pole is in the lower hemisphere. The Cho-Maison MAP was investigated for a range of Weinberg angle, $0.4675\leq\tan\theta_W\leq10$, and Higgs self-coupling, $0\leq\beta\leq1.7704$. Magnetic dipole moment ($\mu_m$) and pole separation ($d_z$) of the numerical solutions are calculated and analyzed. Total energy of the system, however, is infinite due to point singularities at the locations of monopoles.
1402.6580
Alexei Smirnov Yu
Alexei Yu. Smirnov
Theory of neutrino masses and mixing
13 pages, Talk given at the "Pontecorvo 100" Symposium, Pisa, Italy, September 18 - 20, 2013
null
10.1393/ncc/i2014-11761-y
IC.01.2014
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In spite of enormous experimental progress in determination of the neutrino parameters, theory of neutrino mass and mixing is still on the cross-roads. Guidelines could be (i) the connection between zero neutrino charges (and therefore a possibility to be Majorana particle), smallness of the neutrino mass and large lepton mixing, (ii) joint description of leptons and quarks, (iii) existence of the right handed (RH) neutrinos without special quantum numbers. Properties of the RH neutrinos and the UV completion of the seesaw may turn out to be the key to understand the neutrino mass and mixing. In view of the LHC results minimalistic scenarios like $\nu$MSM look rather plausible. Still the GUT's with additional hidden sector, QLC, high scale flavor symmetries are appealing. Concerning mixing, the main issue is "symmetry or no symmetry" behind the observed pattern. The symmetry group condition is useful tool to study consequences of symmetries and to perform "symmetry building". Sterile neutrinos are challenge but also opportunity for the present theoretical constructions.
[ { "created": "Wed, 26 Feb 2014 15:46:58 GMT", "version": "v1" } ]
2022-03-02
[ [ "Smirnov", "Alexei Yu.", "" ] ]
In spite of enormous experimental progress in determination of the neutrino parameters, theory of neutrino mass and mixing is still on the cross-roads. Guidelines could be (i) the connection between zero neutrino charges (and therefore a possibility to be Majorana particle), smallness of the neutrino mass and large lepton mixing, (ii) joint description of leptons and quarks, (iii) existence of the right handed (RH) neutrinos without special quantum numbers. Properties of the RH neutrinos and the UV completion of the seesaw may turn out to be the key to understand the neutrino mass and mixing. In view of the LHC results minimalistic scenarios like $\nu$MSM look rather plausible. Still the GUT's with additional hidden sector, QLC, high scale flavor symmetries are appealing. Concerning mixing, the main issue is "symmetry or no symmetry" behind the observed pattern. The symmetry group condition is useful tool to study consequences of symmetries and to perform "symmetry building". Sterile neutrinos are challenge but also opportunity for the present theoretical constructions.
1711.06031
Anatoly Radyushkin
Anatoly Radyushkin
Quasi-PDFs and pseudo-PDFs
11 pages, Talk at QCD Evolution 2017 Workshop
null
null
JLAB-THY-17-2601
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the physical nature of quasi-PDFs, especially the reasons for the strong nonperturbative evolution pattern which they reveal in actual lattice gauge calculations. We argue that quasi-PDFs may be treated as hybrids of PDFs and the rest-frame momentum distributions of partons. The latter is also responsible for the transverse momentum dependence of TMDs. The resulting convolution structure of quasi-PDFs necessitates using large probing momenta $p_3 \gtrsim 3$ GeV to get reasonably close to the PDF limit. To deconvolute the rest-frame distribution effects, we propose to use a method based directly on the coordinate representation. We treat matrix elements $M(z_3,p_3)$ as distributions ${\cal M} (\nu, z_3^2)$ depending on the Ioffe-time $\nu = p_3 z_3$ and the distance parameter $z_3^2$. The rest-frame spatial distribution is given by ${\cal M} (0, z_3^2)$. Using the reduced Ioffe function ${\mathfrak M} (\nu, z_3^2) \equiv {\cal M} (\nu, z_3^2)/ {\cal M} (0, z_3^2)$ we divide out the rest frame effects,including the notorious link renormalization factors. The $\nu$-dependence remains intact and determines the shape of PDFs in the small $z_3$ region. The residual $z_3^2$ dependence of the ${\mathfrak M} (\nu, z_3^2)$ is governed by perturbative evolution. The Fourier transform of ${\cal M} (\nu, z_3^2)$ produces pseudo-PDFs ${\cal P}(x, z_3^2)$ that generalize the light-front PDFs onto spacelike intervals. On the basis of these findings we propose a new method for extraction of PDFs from lattice calculations.
[ { "created": "Thu, 16 Nov 2017 11:25:57 GMT", "version": "v1" } ]
2017-11-17
[ [ "Radyushkin", "Anatoly", "" ] ]
We discuss the physical nature of quasi-PDFs, especially the reasons for the strong nonperturbative evolution pattern which they reveal in actual lattice gauge calculations. We argue that quasi-PDFs may be treated as hybrids of PDFs and the rest-frame momentum distributions of partons. The latter is also responsible for the transverse momentum dependence of TMDs. The resulting convolution structure of quasi-PDFs necessitates using large probing momenta $p_3 \gtrsim 3$ GeV to get reasonably close to the PDF limit. To deconvolute the rest-frame distribution effects, we propose to use a method based directly on the coordinate representation. We treat matrix elements $M(z_3,p_3)$ as distributions ${\cal M} (\nu, z_3^2)$ depending on the Ioffe-time $\nu = p_3 z_3$ and the distance parameter $z_3^2$. The rest-frame spatial distribution is given by ${\cal M} (0, z_3^2)$. Using the reduced Ioffe function ${\mathfrak M} (\nu, z_3^2) \equiv {\cal M} (\nu, z_3^2)/ {\cal M} (0, z_3^2)$ we divide out the rest frame effects,including the notorious link renormalization factors. The $\nu$-dependence remains intact and determines the shape of PDFs in the small $z_3$ region. The residual $z_3^2$ dependence of the ${\mathfrak M} (\nu, z_3^2)$ is governed by perturbative evolution. The Fourier transform of ${\cal M} (\nu, z_3^2)$ produces pseudo-PDFs ${\cal P}(x, z_3^2)$ that generalize the light-front PDFs onto spacelike intervals. On the basis of these findings we propose a new method for extraction of PDFs from lattice calculations.
hep-ph/0412190
Junhai Kang
Junhai Kang and Paul Langacker
Z' Discovery Limits For Supersymmetric E_6 Models
25 pages, 21 figures
Phys.Rev.D71:035014,2005
10.1103/PhysRevD.71.035014
UPR-1076-T
hep-ph
null
We study how the exotic particles and supersymmetric partners would affect the discovery limit at the Tevatron and LHC for neutral gauge bosons in generic E_6 models. We examine the Z' decay in the extreme case that all of the particles are massless, then consider how the masses of non-standard model particles will affect the discovery limit. We also calculate the discovery limit for a supersymmetric E_6 model with a secluded sector as a concrete example of a model with a definite set of exotic particles. Its discovery limit is small compared with other E_6 models due to the U'(1) charge assignment.
[ { "created": "Tue, 14 Dec 2004 16:46:16 GMT", "version": "v1" } ]
2011-03-23
[ [ "Kang", "Junhai", "" ], [ "Langacker", "Paul", "" ] ]
We study how the exotic particles and supersymmetric partners would affect the discovery limit at the Tevatron and LHC for neutral gauge bosons in generic E_6 models. We examine the Z' decay in the extreme case that all of the particles are massless, then consider how the masses of non-standard model particles will affect the discovery limit. We also calculate the discovery limit for a supersymmetric E_6 model with a secluded sector as a concrete example of a model with a definite set of exotic particles. Its discovery limit is small compared with other E_6 models due to the U'(1) charge assignment.
hep-ph/9707286
Igor Halperin
Igor Halperin and Ariel Zhitnitsky
On Topological Susceptibility, Vacuum Energy and Theta Dependence in Gluodynamics
Details of the derivation are clarified, changes in discussions, new references are added
Mod.Phys.Lett. A13 (1998) 1955-1967
10.1142/S0217732398002060
null
hep-ph hep-lat hep-th
null
We suggest that the topological susceptibility in gluodynamics can be found in terms of the gluon condensate using renormalizability and heavy fermion representation of the anomaly. Analogous relations can be also obtained for other zero momentum correlation functions involving the topological density operator. Using these relations, we find the theta dependence of the condensates <GG>, <G \tilde{G}> and of the partition function for small theta and an arbitrary number of colors.
[ { "created": "Wed, 9 Jul 1997 00:49:01 GMT", "version": "v1" }, { "created": "Mon, 15 Jun 1998 22:37:20 GMT", "version": "v2" } ]
2009-10-30
[ [ "Halperin", "Igor", "" ], [ "Zhitnitsky", "Ariel", "" ] ]
We suggest that the topological susceptibility in gluodynamics can be found in terms of the gluon condensate using renormalizability and heavy fermion representation of the anomaly. Analogous relations can be also obtained for other zero momentum correlation functions involving the topological density operator. Using these relations, we find the theta dependence of the condensates <GG>, <G \tilde{G}> and of the partition function for small theta and an arbitrary number of colors.
1512.05355
Marco Sampaio
Raul Costa, Margarete M\"uhlleitner, Marco O. P. Sampaio, Rui Santos
Singlet Extensions of the Standard Model at LHC Run 2: Benchmarks and Comparison with the NMSSM
49 pages, 6 figures. Improved text, updated samples and figures. Conclusions unchanged. To appear in JHEP
null
10.1007/JHEP06(2016)034
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Complex singlet extension of the Standard Model (CxSM) is the simplest extension that provides scenarios for Higgs pair production with different masses. The model has two interesting phases: the dark matter phase, with a Standard Model-like Higgs boson, a new scalar and a dark matter candidate; and the broken phase, with all three neutral scalars mixing. In the latter phase Higgs decays into a pair of two different Higgs bosons are possible. In this study we analyse Higgs-to-Higgs decays in the framework of singlet extensions of the Standard Model (SM), with focus on the CxSM. After demonstrating that scenarios with large rates for such chain decays are possible we perform a comparison between the NMSSM and the CxSM. We find that, based on Higgs-to-Higgs decays, the only possibility to distinguish the two models at the LHC run 2 is through final states with two different scalars. This conclusion builds a strong case for searches for final states with two different scalars at the LHC run 2. Finally, we propose a set of benchmark points for the real and complex singlet extensions to be tested at the LHC run 2. They have been chosen such that the discovery prospects of the involved scalars are maximised and they fulfil the dark matter constraints. Furthermore, for some of the points the theory is stable up to high energy scales. For the computation of the decay widths and branching ratios we developed the Fortran code, sHDECAY, which is based on the implementation of the real and complex singlet extensions of the SM in HDECAY.
[ { "created": "Wed, 16 Dec 2015 21:00:04 GMT", "version": "v1" }, { "created": "Thu, 9 Jun 2016 11:13:46 GMT", "version": "v2" } ]
2016-06-10
[ [ "Costa", "Raul", "" ], [ "Mühlleitner", "Margarete", "" ], [ "Sampaio", "Marco O. P.", "" ], [ "Santos", "Rui", "" ] ]
The Complex singlet extension of the Standard Model (CxSM) is the simplest extension that provides scenarios for Higgs pair production with different masses. The model has two interesting phases: the dark matter phase, with a Standard Model-like Higgs boson, a new scalar and a dark matter candidate; and the broken phase, with all three neutral scalars mixing. In the latter phase Higgs decays into a pair of two different Higgs bosons are possible. In this study we analyse Higgs-to-Higgs decays in the framework of singlet extensions of the Standard Model (SM), with focus on the CxSM. After demonstrating that scenarios with large rates for such chain decays are possible we perform a comparison between the NMSSM and the CxSM. We find that, based on Higgs-to-Higgs decays, the only possibility to distinguish the two models at the LHC run 2 is through final states with two different scalars. This conclusion builds a strong case for searches for final states with two different scalars at the LHC run 2. Finally, we propose a set of benchmark points for the real and complex singlet extensions to be tested at the LHC run 2. They have been chosen such that the discovery prospects of the involved scalars are maximised and they fulfil the dark matter constraints. Furthermore, for some of the points the theory is stable up to high energy scales. For the computation of the decay widths and branching ratios we developed the Fortran code, sHDECAY, which is based on the implementation of the real and complex singlet extensions of the SM in HDECAY.
hep-ph/0010333
Timo Paulus
Otto Nachtmann, Timo Paulus
Inelastic diffractive proton-proton scattering in nonperturbative QCD
4 pages, 2 figures, to appear in the Proceedings of the International Workshop on Diffraction 2000, Cetraro, Italy, 2-7 Sept. 2000
Nucl.Phys.Proc.Suppl. 99A (2001) 226-229
10.1016/S0920-5632(01)01339-1
HD-THEP-00-52
hep-ph
null
We examine diffractive proton-proton scattering. Using a functional integral approach we derive the scattering amplitudes, which are governed by the expectation value of lightlike Wegner-Wilson loops. This expectation value is then evaluated using a cumulant expansion and the model of the stochastic vacuum. From the scattering amplitudes we calculate total and differential cross sections for high centre of mass energy and small momentum transfer and compare with experiments.
[ { "created": "Mon, 30 Oct 2000 15:30:14 GMT", "version": "v1" }, { "created": "Tue, 31 Oct 2000 14:33:42 GMT", "version": "v2" } ]
2009-10-31
[ [ "Nachtmann", "Otto", "" ], [ "Paulus", "Timo", "" ] ]
We examine diffractive proton-proton scattering. Using a functional integral approach we derive the scattering amplitudes, which are governed by the expectation value of lightlike Wegner-Wilson loops. This expectation value is then evaluated using a cumulant expansion and the model of the stochastic vacuum. From the scattering amplitudes we calculate total and differential cross sections for high centre of mass energy and small momentum transfer and compare with experiments.
1803.07686
Takashi Shimomura
Munehiro Kubo, Joe Sato, Takashi Shimomura, Yasutaka Takanishi and Masato Yamanaka
Big-bang nucleosynthesis and Leptogenesis in CMSSM
27 pages, 4 figures
Phys. Rev. D 97, 115013 (2018)
10.1103/PhysRevD.97.115013
STUPP-18-233, UME-PP-009, MISC-2018-01
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have investigated the constrained minimal supersymmetric standard model with three right-handed Majorana neutrinos whether there still is a parameter region which is consistent with all existing experimental data/limits such as Leptogenesis and the dark matter abundance and we also can solve the Lithium problem. Using Casas-Ibarra parameterization, we have found that a very narrow parameter space of the complex orthogonal matrix elements where the lightest slepton can have a long lifetime, that is necessary for solving the Lithium problem. Further, under this condition, there is a parameter region that can give an explanation for the experimental observations. We have studied three cases of the right-handed neutrino mass ratio \mbox{\em (i)} $M_{2}=2 \times M_{1}$, \mbox{\em (ii)} $M_{2}=4 \times M_{1}$, \mbox{\em (iii)} $M_{2}=10 \times M_{1}$ while $M_{3}=40 \times M_{1}$ is fixed. We have obtained the mass range of the lightest right-handed neutrino mass that lies between $10^9$ GeV and $10^{11}$ GeV. The important result is that its upper limit is derived by solving the Lithium problem and the lower limit comes from Leptogenesis. Calculated low-energy observables of these parameter sets such as BR($\mu \to e \gamma$) is not yet restricted by experiments and will be verified in the near future.
[ { "created": "Tue, 20 Mar 2018 23:08:09 GMT", "version": "v1" } ]
2018-06-13
[ [ "Kubo", "Munehiro", "" ], [ "Sato", "Joe", "" ], [ "Shimomura", "Takashi", "" ], [ "Takanishi", "Yasutaka", "" ], [ "Yamanaka", "Masato", "" ] ]
We have investigated the constrained minimal supersymmetric standard model with three right-handed Majorana neutrinos whether there still is a parameter region which is consistent with all existing experimental data/limits such as Leptogenesis and the dark matter abundance and we also can solve the Lithium problem. Using Casas-Ibarra parameterization, we have found that a very narrow parameter space of the complex orthogonal matrix elements where the lightest slepton can have a long lifetime, that is necessary for solving the Lithium problem. Further, under this condition, there is a parameter region that can give an explanation for the experimental observations. We have studied three cases of the right-handed neutrino mass ratio \mbox{\em (i)} $M_{2}=2 \times M_{1}$, \mbox{\em (ii)} $M_{2}=4 \times M_{1}$, \mbox{\em (iii)} $M_{2}=10 \times M_{1}$ while $M_{3}=40 \times M_{1}$ is fixed. We have obtained the mass range of the lightest right-handed neutrino mass that lies between $10^9$ GeV and $10^{11}$ GeV. The important result is that its upper limit is derived by solving the Lithium problem and the lower limit comes from Leptogenesis. Calculated low-energy observables of these parameter sets such as BR($\mu \to e \gamma$) is not yet restricted by experiments and will be verified in the near future.
1303.6524
Bernd Kniehl
Mathias Butenschoen, Zhi-Guo He, Bernd A.Kniehl
NLO NRQCD disfavors the interpretation of X(3872) as $\chi_{c1}(2P)$
5 pages, 1 figure, 1 table; three-parameter fit included, reference updated; accepted for publication as Rapid Communication in Physical Review D
null
null
DESY 13-057, UWTHPH-2013-6
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study $\chi_{c1}(2P)$ inclusive hadroproduction at next-to-leading order (NLO), both in $\alpha_s$ and $v^2$, within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), including the color-singlet $^3P_1^{[1]}$ and color-octet $^3S_1^{[8]}$ $c\bar c$ Fock states as well as the mixing of the latter with the $^3D_1^{[8]}$ state. Assuming the recently discovered X(3872) hadron to be the $J^{PC}=1^{++}$ charmonium state $\chi_{c1}(2P)$, we perform a fit to the cross sections measured by the CDF, CMS, and LHCb Collaborations. We either obtain an unacceptably high value of $\chi^2$, a value of $|R_{2P}^\prime(0)|$ incompatible with well-established potential models, or an intolerable violation of the NRQCD velocity rules. We thus conclude that NLO NRQCD is inconsistent with the hypothesis $X(3872)\equiv\chi_{c1}(2P)$.
[ { "created": "Tue, 26 Mar 2013 15:19:56 GMT", "version": "v1" }, { "created": "Fri, 7 Jun 2013 15:04:16 GMT", "version": "v2" }, { "created": "Thu, 18 Jul 2013 02:49:48 GMT", "version": "v3" } ]
2013-07-19
[ [ "Butenschoen", "Mathias", "" ], [ "He", "Zhi-Guo", "" ], [ "Kniehl", "Bernd A.", "" ] ]
We study $\chi_{c1}(2P)$ inclusive hadroproduction at next-to-leading order (NLO), both in $\alpha_s$ and $v^2$, within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), including the color-singlet $^3P_1^{[1]}$ and color-octet $^3S_1^{[8]}$ $c\bar c$ Fock states as well as the mixing of the latter with the $^3D_1^{[8]}$ state. Assuming the recently discovered X(3872) hadron to be the $J^{PC}=1^{++}$ charmonium state $\chi_{c1}(2P)$, we perform a fit to the cross sections measured by the CDF, CMS, and LHCb Collaborations. We either obtain an unacceptably high value of $\chi^2$, a value of $|R_{2P}^\prime(0)|$ incompatible with well-established potential models, or an intolerable violation of the NRQCD velocity rules. We thus conclude that NLO NRQCD is inconsistent with the hypothesis $X(3872)\equiv\chi_{c1}(2P)$.
2406.15014
Sergey Mikhailov
S. V. Mikhailov
Adler function, Bjorken polarized Sum Rule -- confirmation of elements of the $\{\beta\}$-expansion and the diagrams
In version 2: Eqs.(2.3),(A2), misprints are corrected, Sec.3 is supplemented by new test. 14 pages, 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Different ways exist to obtain the elements of the $\{\beta \}$-expansion for renormgroup invariant quantities. Here we consider independent confirmation within the standard QCD of a number of our results [1] for the values of elements of this expansion for the nonsinglet Adler $D_A$-function, Bjorken polarized sum rules $S^{Bjp}$ up to the order N$^4$LO. We suggest an approach to estimate the results of high order QCD calculations using a smaller number of diagrams of the specific type. This type is based on a proposed generalization of Naive NonAbelianization.
[ { "created": "Fri, 21 Jun 2024 09:42:47 GMT", "version": "v1" }, { "created": "Fri, 19 Jul 2024 13:13:28 GMT", "version": "v2" } ]
2024-07-22
[ [ "Mikhailov", "S. V.", "" ] ]
Different ways exist to obtain the elements of the $\{\beta \}$-expansion for renormgroup invariant quantities. Here we consider independent confirmation within the standard QCD of a number of our results [1] for the values of elements of this expansion for the nonsinglet Adler $D_A$-function, Bjorken polarized sum rules $S^{Bjp}$ up to the order N$^4$LO. We suggest an approach to estimate the results of high order QCD calculations using a smaller number of diagrams of the specific type. This type is based on a proposed generalization of Naive NonAbelianization.
2112.07685
Zoltan Ligeti
Zoltan Ligeti, Michael Luke, Frank J. Tackmann
Theoretical predictions for inclusive $B\to X_u \tau \bar\nu$ decay
6 pages, published version
null
null
DESY 21-215
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
With the expected large increase in data sets, previously not measured decays will be studied at Belle II. We derive standard model predictions for the $B\to X_u \tau\bar\nu$ decay rate and distributions. The region in the lepton energy spectrum where higher-dimension operators in the local OPE need to be resummed into the $b$-quark light-cone distribution function is a significantly greater fraction of the phase space than for massless leptons. The finite $\tau$ mass has the novel effect of shifting and squeezing how the distribution function enters the lepton energy spectrum. We also derive new predictions for the $\tau$ polarization.
[ { "created": "Tue, 14 Dec 2021 19:00:02 GMT", "version": "v1" }, { "created": "Fri, 6 May 2022 16:45:35 GMT", "version": "v2" } ]
2022-05-09
[ [ "Ligeti", "Zoltan", "" ], [ "Luke", "Michael", "" ], [ "Tackmann", "Frank J.", "" ] ]
With the expected large increase in data sets, previously not measured decays will be studied at Belle II. We derive standard model predictions for the $B\to X_u \tau\bar\nu$ decay rate and distributions. The region in the lepton energy spectrum where higher-dimension operators in the local OPE need to be resummed into the $b$-quark light-cone distribution function is a significantly greater fraction of the phase space than for massless leptons. The finite $\tau$ mass has the novel effect of shifting and squeezing how the distribution function enters the lepton energy spectrum. We also derive new predictions for the $\tau$ polarization.
hep-ph/0208227
Oleg P. Sushkov
A.I. Milstein, O.P. Sushkov, I.S. Terekhov
Radiative corrections and parity nonconservation in heavy atoms
4 pages, 4 figures
Phys.Rev.Lett. 89 (2002) 283003
10.1103/PhysRevLett.89.283003
null
hep-ph nucl-th physics.atom-ph
null
The self-energy and the vertex radiative corrections to the effect of parity nonconservation in heavy atoms are calculated analytically in orders Z alpha^2 and Z^2 alpha^3 ln(lambda_C/r_0), where lambda_C and r_0 being the Compton wavelength and the nuclear radius, respectively. The value of the radiative correction is -0.85% for Cs and -1.41% for Tl. Using these results we have performed analysis of the experimental data on atomic parity nonconservation. The obtained values of the nuclear weak charge, Q_W=-72.90(28)_{exp}(35)_{theor} for Cs, and Q_W=-116.7(1.2)_{exp}(3.4)_{theor} for Tl, agree with predictions of the standard model. As an application of our approach we have also calculated analytically dependence of the Lamb shift on the finite nuclear size.
[ { "created": "Sun, 25 Aug 2002 11:03:48 GMT", "version": "v1" } ]
2009-11-07
[ [ "Milstein", "A. I.", "" ], [ "Sushkov", "O. P.", "" ], [ "Terekhov", "I. S.", "" ] ]
The self-energy and the vertex radiative corrections to the effect of parity nonconservation in heavy atoms are calculated analytically in orders Z alpha^2 and Z^2 alpha^3 ln(lambda_C/r_0), where lambda_C and r_0 being the Compton wavelength and the nuclear radius, respectively. The value of the radiative correction is -0.85% for Cs and -1.41% for Tl. Using these results we have performed analysis of the experimental data on atomic parity nonconservation. The obtained values of the nuclear weak charge, Q_W=-72.90(28)_{exp}(35)_{theor} for Cs, and Q_W=-116.7(1.2)_{exp}(3.4)_{theor} for Tl, agree with predictions of the standard model. As an application of our approach we have also calculated analytically dependence of the Lamb shift on the finite nuclear size.
hep-ph/9711269
null
A. G. Grozin
Recent progress on HQET lagrangian
LaTeX2e, 13 pages, figures included; Invited plenary talk at the IV Int. Workshop on Progress in Heavy Quark Physics, Rostock, September 20-22
null
null
null
hep-ph
null
HQET lagrangian up to $1/m^3$ terms is discussed. Consequences of reparameterization invariance are considered. Results for the chromomagnetic interaction coefficient at two loops, and in all orders in the large--$\beta_1$ approximation, are presented.
[ { "created": "Sun, 9 Nov 1997 07:37:33 GMT", "version": "v1" } ]
2007-05-23
[ [ "Grozin", "A. G.", "" ] ]
HQET lagrangian up to $1/m^3$ terms is discussed. Consequences of reparameterization invariance are considered. Results for the chromomagnetic interaction coefficient at two loops, and in all orders in the large--$\beta_1$ approximation, are presented.
hep-ph/9909437
Emanuel Norrbin
E. Norrbin
Heavy Quark Production Asymmetries
6 pages, 6 figures, to appear in the Proceedings of the International Europhysics Conference on High Energy Physics, Tampere, Finland, 15-21 July 1999, edited by K. Huitu, H. Kurki-Suonio and J. Maalampi
null
null
LU TP 99-28
hep-ph
null
In the hadroproduction of charm (or heavy flavours in general) in the context of string fragmentation, the pull of a beam remnant at the other end of a string may give a charm hadron more energy than the perturbatively produced one. The collapse of a low-mass string to a single hadron is the extreme case in this direction, and gives rise to asymmetries between leading and non-leading charm hadrons. We study these phenomena within the Lund string fragmentation model and improve the modelling in part by a consideration of hadroproduction data. Applications include heavy quark production in any collision between hadron-like particles such as \gamma p at HERA and pp at HERA-B or the LHC.
[ { "created": "Mon, 20 Sep 1999 15:49:34 GMT", "version": "v1" } ]
2007-05-23
[ [ "Norrbin", "E.", "" ] ]
In the hadroproduction of charm (or heavy flavours in general) in the context of string fragmentation, the pull of a beam remnant at the other end of a string may give a charm hadron more energy than the perturbatively produced one. The collapse of a low-mass string to a single hadron is the extreme case in this direction, and gives rise to asymmetries between leading and non-leading charm hadrons. We study these phenomena within the Lund string fragmentation model and improve the modelling in part by a consideration of hadroproduction data. Applications include heavy quark production in any collision between hadron-like particles such as \gamma p at HERA and pp at HERA-B or the LHC.
hep-ph/9912439
Botje
M. Botje
A QCD analysis of HERA and fixed target structure function data
Latex source, 14 pages, 3 tables, 15 figures
Eur.Phys.J.C14:285-297,2000
10.1007/s100520000358
DESY-99-038, NIKHEF-99-011
hep-ph
null
The parton momentum density distributions in the proton are determined from a next-to-leading order QCD analysis of structure functions measured at HERA and by fixed target experiments. Also included are data on the difference of the up and down anti-quark distributions. The uncertainties in the parton densities, structure functions and related cross sections are estimated from the experimental errors and those on the input parameters of the fit. Several QCD predictions obtained from this analysis are calculated and compared to data. The parton densites including the full error information is made available on a computer readable file.
[ { "created": "Tue, 21 Dec 1999 11:03:10 GMT", "version": "v1" } ]
2011-09-13
[ [ "Botje", "M.", "" ] ]
The parton momentum density distributions in the proton are determined from a next-to-leading order QCD analysis of structure functions measured at HERA and by fixed target experiments. Also included are data on the difference of the up and down anti-quark distributions. The uncertainties in the parton densities, structure functions and related cross sections are estimated from the experimental errors and those on the input parameters of the fit. Several QCD predictions obtained from this analysis are calculated and compared to data. The parton densites including the full error information is made available on a computer readable file.
1104.3286
Shinya Matsuzaki
Masayasu Harada, Shinya Matsuzaki and Koichi Yamawaki
Anomalous $\omega$-$Z$-$\gamma$ Vertex from Hidden Local Symmetry
15 pages, 4 eps figures, latex; typo fixed, two references added, to appear in PRD
Phys.Rev.D84:036010,2011
10.1103/PhysRevD.84.036010
MISC-2011-08
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We formulate the general form of omega-Z-gamma vertex in the framework based on the hidden local symmetry (HLS), which arises from the gauge invariant terms for intrinsic parity-odd (IP-odd) part of the effective action. Those terms are given as the homogeneous part of the general solution (having free parameters) to the Wess-Zumino (WZ) anomaly equation and hence are not determined by the anomaly, in sharp contrast to the Harvey-Hill-Hill (HHH) action where the relevant vertex is claimed to be uniquely determined by the anomaly. We show that, even in the framework that HHH was based on, the omega-Z-gamma vertex is actually not determined by the anomaly but by the homogeneous (anomaly-free) part of the general solution to the WZ anomaly equation having free parameters in the same way as in the HLS formulation: The HHH action is just a particular choice of the free parameters in the general solution. We further show that the omega-Z-gamma vertex related to the neutrino (nu) - nucleon (N) scattering cross section sigma(nu N -> nu N (N')gamma) is determined not by the anomaly but by the anomaly-free part of the general solution having free parameters. Nevertheless we find that the cross section sigma(nu N -> nu N(N')gamma) is related through the Ward-Takahashi identity to Gamma(omega -> pi^0 gamma) which has the same parameter-dependence as that of sigma(nu N -> nu N(N')gamma) and hence the ratio sigma(nu N -> nu N(N')gamma)/Gamma(omega -> pi^0 gamma) is fixed independently of these free parameters. Other set of the free parameters of the general solution can be fixed to make the best fit of the omega -> pi^0 l^+ l^- process, which substantially differs from the HHH action. This gives a prediction of the cross section sigma(nu N -> nu N (N')gamma^*(l^+ l^-)) to be tested at nu-N collision experiments in the future.
[ { "created": "Sun, 17 Apr 2011 08:14:39 GMT", "version": "v1" }, { "created": "Tue, 9 Aug 2011 04:14:16 GMT", "version": "v2" } ]
2011-09-13
[ [ "Harada", "Masayasu", "" ], [ "Matsuzaki", "Shinya", "" ], [ "Yamawaki", "Koichi", "" ] ]
We formulate the general form of omega-Z-gamma vertex in the framework based on the hidden local symmetry (HLS), which arises from the gauge invariant terms for intrinsic parity-odd (IP-odd) part of the effective action. Those terms are given as the homogeneous part of the general solution (having free parameters) to the Wess-Zumino (WZ) anomaly equation and hence are not determined by the anomaly, in sharp contrast to the Harvey-Hill-Hill (HHH) action where the relevant vertex is claimed to be uniquely determined by the anomaly. We show that, even in the framework that HHH was based on, the omega-Z-gamma vertex is actually not determined by the anomaly but by the homogeneous (anomaly-free) part of the general solution to the WZ anomaly equation having free parameters in the same way as in the HLS formulation: The HHH action is just a particular choice of the free parameters in the general solution. We further show that the omega-Z-gamma vertex related to the neutrino (nu) - nucleon (N) scattering cross section sigma(nu N -> nu N (N')gamma) is determined not by the anomaly but by the anomaly-free part of the general solution having free parameters. Nevertheless we find that the cross section sigma(nu N -> nu N(N')gamma) is related through the Ward-Takahashi identity to Gamma(omega -> pi^0 gamma) which has the same parameter-dependence as that of sigma(nu N -> nu N(N')gamma) and hence the ratio sigma(nu N -> nu N(N')gamma)/Gamma(omega -> pi^0 gamma) is fixed independently of these free parameters. Other set of the free parameters of the general solution can be fixed to make the best fit of the omega -> pi^0 l^+ l^- process, which substantially differs from the HHH action. This gives a prediction of the cross section sigma(nu N -> nu N (N')gamma^*(l^+ l^-)) to be tested at nu-N collision experiments in the future.
1908.08333
Aaron Park
Aaron Park, Su Houng Lee
Intrinsic three-body nuclear interaction from a constituent quark model
8 pages, 1 figure
Phys. Rev. C 100, 055201 (2019)
10.1103/PhysRevC.100.055201
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the short distance part of the intrinsic three-nucleon interaction in a constituent quark model with color-spin interaction. For that purpose we first calculate the transformation coefficient between the tribaryon configuration and their corresponding three baryon basis. Using a formula for the intrinsic three-body interaction in terms of a tribaryon configuration, we find that after subtracting the corresponding two-baryon contributions, the intrinsic three-body interaction vanishes in flavor SU(3) symmetric limit for all quantum numbers for the three nucleon states. We further find that the intrinsic three-body interaction also vanishes for flavor-spin type of quark interaction.
[ { "created": "Thu, 22 Aug 2019 12:23:23 GMT", "version": "v1" } ]
2019-11-13
[ [ "Park", "Aaron", "" ], [ "Lee", "Su Houng", "" ] ]
We study the short distance part of the intrinsic three-nucleon interaction in a constituent quark model with color-spin interaction. For that purpose we first calculate the transformation coefficient between the tribaryon configuration and their corresponding three baryon basis. Using a formula for the intrinsic three-body interaction in terms of a tribaryon configuration, we find that after subtracting the corresponding two-baryon contributions, the intrinsic three-body interaction vanishes in flavor SU(3) symmetric limit for all quantum numbers for the three nucleon states. We further find that the intrinsic three-body interaction also vanishes for flavor-spin type of quark interaction.
1101.6053
Ayan Paul
Ayan Paul, Ikaros I. Bigi, Stefan Recksiegel
On $D\to X_u l^+ l^-$ within the Standard Model and Frameworks like the Littlest Higgs Model with T Parity
24 Pages, 12 figures. V2 contains corrections to the Appendix A. V3 fixes an error in eq. 10
Phys.Rev.D83: 114006, 2011
10.1103/PhysRevD.83.114006
UND-HEP-10-BIG07, TUM-HEP-791/11
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $D\to X_u l^+ l^-$ transitions -- branching ratios, forward-backward asymmetry $A^c_{FB}$, the CP asymmetry $A^c_{CP}$ and the CP asymmetry in the forward-backward asymmetry $A^{CP}_{FB}$ -- have two sources: for $D^{\pm}$ they represent a pure $\Delta C=1$ & $\Delta Q=0$ current interaction whereas neutral $D$ mesons can also communicate via their anti-hadron. Standard Model (SM) contributions to BR$(D\to X_u l^+ l^-)$ come primarily from long distance dynamics, which overshadow short distance contributions by several orders of magnitude; still they fall much below the present upper experimental bounds. Even the SM contributions to $A^c_{FB}$, $A^c_{CP}$ and $A^{CP}_{FB}$ are tiny, quite unlike in beauty hadrons. The branching ratios are hardly dented by contributions from the Littlest Higgs Models with T parity (LHT) even in the short distance regime, let alone in the SM long distances dynamics. Yet the asymmetries $A^c_{FB}$, $A^c_{CP}$ and $A^{CP}_{FB}$ in these New Physics models can be enhanced over SM predictions, as they arise purely from short distance dynamics; this can occur in particular for $A^c_{FB}$ and $A^{CP}_{FB}$ which get enhanced by orders of magnitudes. Even such enhancements hardly reach absolute sizes for observable experimental effects for $A^c_{FB}$ and $A^c_{CP}$. However LHT contributions to $A^{CP}_{FB}$ could be measured in experiments like the LHCb and the SuperB Collaboration. These results lead us to draw further conclusions on FCNCs within LHT-like models through some simple scaling arguments that encapsulate the essence of flavour dynamics in and beyond the Standard Model.
[ { "created": "Mon, 31 Jan 2011 19:28:20 GMT", "version": "v1" }, { "created": "Wed, 1 Jun 2011 16:57:52 GMT", "version": "v2" }, { "created": "Thu, 20 Oct 2016 22:30:55 GMT", "version": "v3" } ]
2016-10-24
[ [ "Paul", "Ayan", "" ], [ "Bigi", "Ikaros I.", "" ], [ "Recksiegel", "Stefan", "" ] ]
The $D\to X_u l^+ l^-$ transitions -- branching ratios, forward-backward asymmetry $A^c_{FB}$, the CP asymmetry $A^c_{CP}$ and the CP asymmetry in the forward-backward asymmetry $A^{CP}_{FB}$ -- have two sources: for $D^{\pm}$ they represent a pure $\Delta C=1$ & $\Delta Q=0$ current interaction whereas neutral $D$ mesons can also communicate via their anti-hadron. Standard Model (SM) contributions to BR$(D\to X_u l^+ l^-)$ come primarily from long distance dynamics, which overshadow short distance contributions by several orders of magnitude; still they fall much below the present upper experimental bounds. Even the SM contributions to $A^c_{FB}$, $A^c_{CP}$ and $A^{CP}_{FB}$ are tiny, quite unlike in beauty hadrons. The branching ratios are hardly dented by contributions from the Littlest Higgs Models with T parity (LHT) even in the short distance regime, let alone in the SM long distances dynamics. Yet the asymmetries $A^c_{FB}$, $A^c_{CP}$ and $A^{CP}_{FB}$ in these New Physics models can be enhanced over SM predictions, as they arise purely from short distance dynamics; this can occur in particular for $A^c_{FB}$ and $A^{CP}_{FB}$ which get enhanced by orders of magnitudes. Even such enhancements hardly reach absolute sizes for observable experimental effects for $A^c_{FB}$ and $A^c_{CP}$. However LHT contributions to $A^{CP}_{FB}$ could be measured in experiments like the LHCb and the SuperB Collaboration. These results lead us to draw further conclusions on FCNCs within LHT-like models through some simple scaling arguments that encapsulate the essence of flavour dynamics in and beyond the Standard Model.
1903.10434
David M. Straub
Jason Aebischer, Wolfgang Altmannshofer, Diego Guadagnoli, Meril Reboud, Peter Stangl, David M. Straub
B-decay discrepancies after Moriond 2019
41 pages, 20 figures, 3 tables. Originally presented at Moriond EW 2019 on March 22, 2019. v2: Numerics updated including the Belle RD(*) update, clarifications and references added
null
10.1140/epjc/s10052-020-7817-x
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Following the updated measurement of the lepton flavour universality (LFU) ratio R_K in B -> Kll decays by LHCb, as well as a number of further measurements, e.g. R_K* by Belle and B_s -> mu mu by ATLAS, we analyse the global status of new physics in b -> s transitions in the weak effective theory at the b-quark scale, in the Standard Model effective theory at the electroweak scale, and in simplified models of new physics. We find that the data continues to strongly prefer a solution with new physics in semi-leptonic Wilson coefficients. A purely muonic contribution to the combination C_9 = -C_10, well suited to UV-complete interpretations, is now favoured with respect to a muonic contribution to C_9 only. An even better fit is obtained by allowing an additional LFU shift in C_9. Such a shift can be renormalization-group induced from four-fermion operators above the electroweak scale, in particular from semi-tauonic operators, able to account for the potential discrepancies in b -> c transitions. This scenario is naturally realized in the simplified U_1 leptoquark model. We also analyse simplified models where a LFU effect in b -> sll is induced radiatively from four-quark operators and show that such a setup is on the brink of exclusion by LHC di-jet resonance searches.
[ { "created": "Mon, 25 Mar 2019 16:15:39 GMT", "version": "v1" }, { "created": "Tue, 6 Aug 2019 11:21:45 GMT", "version": "v2" } ]
2020-04-22
[ [ "Aebischer", "Jason", "" ], [ "Altmannshofer", "Wolfgang", "" ], [ "Guadagnoli", "Diego", "" ], [ "Reboud", "Meril", "" ], [ "Stangl", "Peter", "" ], [ "Straub", "David M.", "" ] ]
Following the updated measurement of the lepton flavour universality (LFU) ratio R_K in B -> Kll decays by LHCb, as well as a number of further measurements, e.g. R_K* by Belle and B_s -> mu mu by ATLAS, we analyse the global status of new physics in b -> s transitions in the weak effective theory at the b-quark scale, in the Standard Model effective theory at the electroweak scale, and in simplified models of new physics. We find that the data continues to strongly prefer a solution with new physics in semi-leptonic Wilson coefficients. A purely muonic contribution to the combination C_9 = -C_10, well suited to UV-complete interpretations, is now favoured with respect to a muonic contribution to C_9 only. An even better fit is obtained by allowing an additional LFU shift in C_9. Such a shift can be renormalization-group induced from four-fermion operators above the electroweak scale, in particular from semi-tauonic operators, able to account for the potential discrepancies in b -> c transitions. This scenario is naturally realized in the simplified U_1 leptoquark model. We also analyse simplified models where a LFU effect in b -> sll is induced radiatively from four-quark operators and show that such a setup is on the brink of exclusion by LHC di-jet resonance searches.
hep-ph/0606039
Ernest Ma
Ernest Ma (UC Riverside)
Lepton family symmetries for neutrino masses and mixing
14 pages, no figure, talk at WHEPP-9
Pramana67:803-812,2006
10.1007/s12043-006-0093-y
UCRHEP-T413 (June 2006)
hep-ph
null
I review some of the recent progress (up to December 2005) in applying non-Abelian discrete symmetries to the family structure of leptons, with particular emphasis on the tribimaximal mixing ansatz of Harrison, Perkins, and Scott.
[ { "created": "Sat, 3 Jun 2006 15:32:21 GMT", "version": "v1" } ]
2008-11-26
[ [ "Ma", "Ernest", "", "UC Riverside" ] ]
I review some of the recent progress (up to December 2005) in applying non-Abelian discrete symmetries to the family structure of leptons, with particular emphasis on the tribimaximal mixing ansatz of Harrison, Perkins, and Scott.
1802.03025
Dan Hooper
Dan Hooper and Samuel D. McDermott
Robust Constraints and Novel Gamma-Ray Signatures of Dark Matter That Interacts Strongly With Nucleons
11 pages, 4 figures
Phys. Rev. D 97, 115006 (2018)
10.1103/PhysRevD.97.115006
FERMILAB-PUB-18-032-A
hep-ph astro-ph.CO astro-ph.GA astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Due to shielding, direct detection experiments are in some cases insensitive to dark matter candidates with very large scattering cross sections with nucleons. In this paper, we revisit this class of models, and derive a simple analytic criterion for conservative but robust direct detection limits. While large spin-independent cross sections seem to be ruled out, we identify potentially viable parameter space for dark matter with a spin-dependent cross section with nucleons in the range of $10^{-27} {\rm cm}^2 < \sigma_{{\rm DM}-p} < 10^{-24} \, {\rm cm}^{2}$. With these parameters, cosmic-ray scattering with dark matter in the extended halo of the Milky Way could generate a novel and distinctive gamma-ray signal at high galactic latitudes. Such a signal could be observable by Fermi or future space-based gamma-ray telescopes.
[ { "created": "Thu, 8 Feb 2018 19:06:45 GMT", "version": "v1" }, { "created": "Mon, 19 Mar 2018 22:16:46 GMT", "version": "v2" } ]
2018-06-13
[ [ "Hooper", "Dan", "" ], [ "McDermott", "Samuel D.", "" ] ]
Due to shielding, direct detection experiments are in some cases insensitive to dark matter candidates with very large scattering cross sections with nucleons. In this paper, we revisit this class of models, and derive a simple analytic criterion for conservative but robust direct detection limits. While large spin-independent cross sections seem to be ruled out, we identify potentially viable parameter space for dark matter with a spin-dependent cross section with nucleons in the range of $10^{-27} {\rm cm}^2 < \sigma_{{\rm DM}-p} < 10^{-24} \, {\rm cm}^{2}$. With these parameters, cosmic-ray scattering with dark matter in the extended halo of the Milky Way could generate a novel and distinctive gamma-ray signal at high galactic latitudes. Such a signal could be observable by Fermi or future space-based gamma-ray telescopes.
hep-ph/9610400
Tomislav Prokopec
Tomislav Prokopec, Thomas G. Roos (LNS, Cornell U.)
Lattice study of classical inflaton decay
12 pages LaTeX with standard RevTex macros, uses epsf.sty. 7 postscript figures (included). No changes. Replaced to correct a problem with the figures
Phys.Rev. D55 (1997) 3768-3775
10.1103/PhysRevD.55.3768
CLNS 96/1438
hep-ph astro-ph
null
We study numerically the decay of the inflaton by solving the full non-linear equations of motion on the lattice. We confirm that parametric resonance is effective in transferring energy from the inflaton to a scalar field as long as the self-interactions of the second field are very small. However, in the very broad resonance case (q>>1) the decay rate is limited by scatterings, which significantly slows down the decay. We also find that the inflaton cannot decay via parametric resonance into a scalar field with moderate self-interactions. This means that the preheating stage may be completely absent in many natural inflationary models.
[ { "created": "Thu, 17 Oct 1996 23:45:38 GMT", "version": "v1" }, { "created": "Fri, 18 Oct 1996 00:51:58 GMT", "version": "v2" }, { "created": "Thu, 31 Oct 1996 23:32:50 GMT", "version": "v3" }, { "created": "Thu, 8 May 1997 19:50:23 GMT", "version": "v4" }, { "created": "Thu, 28 Aug 1997 19:00:36 GMT", "version": "v5" } ]
2009-10-30
[ [ "Prokopec", "Tomislav", "", "LNS, Cornell U." ], [ "Roos", "Thomas G.", "", "LNS, Cornell U." ] ]
We study numerically the decay of the inflaton by solving the full non-linear equations of motion on the lattice. We confirm that parametric resonance is effective in transferring energy from the inflaton to a scalar field as long as the self-interactions of the second field are very small. However, in the very broad resonance case (q>>1) the decay rate is limited by scatterings, which significantly slows down the decay. We also find that the inflaton cannot decay via parametric resonance into a scalar field with moderate self-interactions. This means that the preheating stage may be completely absent in many natural inflationary models.
hep-ph/0504230
Qing-Hong Cao
Qing-Hong Cao, Reinhard Schwienhorst, Jorge A. Benitez, Raymond Brock, C.-P. Yuan
Next-to-Leading Order Corrections to Single Top Quark Production and Decay at the Tevatron: 2. $t$-channel Process
46 pages, 47 figures. One typo in LaTeX source file is corrected
Phys.Rev.D72:094027,2005
10.1103/PhysRevD.72.094027
null
hep-ph
null
We present a study of the $t$-channel mode of single top quark production at the upgraded Tevatron $p\bar{p}$ collider, including the next-to-leading order (NLO) QCD corrections to the production and the decay of a single top quark. The narrow width approximation was adopted in order to preserve the spin of the top quark in its production and decay. We discuss the effects of different $O(\alpha_s)$ contributions on the inclusive cross section as well as various kinematic distributions after imposing the relevant cuts to select $t$-channel single top signal events.
[ { "created": "Tue, 26 Apr 2005 00:54:51 GMT", "version": "v1" }, { "created": "Wed, 27 Apr 2005 20:13:30 GMT", "version": "v2" } ]
2011-03-23
[ [ "Cao", "Qing-Hong", "" ], [ "Schwienhorst", "Reinhard", "" ], [ "Benitez", "Jorge A.", "" ], [ "Brock", "Raymond", "" ], [ "Yuan", "C. -P.", "" ] ]
We present a study of the $t$-channel mode of single top quark production at the upgraded Tevatron $p\bar{p}$ collider, including the next-to-leading order (NLO) QCD corrections to the production and the decay of a single top quark. The narrow width approximation was adopted in order to preserve the spin of the top quark in its production and decay. We discuss the effects of different $O(\alpha_s)$ contributions on the inclusive cross section as well as various kinematic distributions after imposing the relevant cuts to select $t$-channel single top signal events.
hep-ph/0410291
Aleksander Filip Zarnecki
P. Niezurawski, A. F. Zarnecki, M. Krawczyk
Model-Independent Determination of CP Violation from Angular Distributions in Higgs Boson Decays to WW and ZZ at the Photon Collider
10 pages, 8 figures
Acta Phys.Polon. B36 (2005) 833-844
null
null
hep-ph
null
The model-independent determination of the Higgs-boson CP properties at the Photon Collider at TESLA has been studied in detail, for masses between 200 and 350 GeV, using realistic luminosity spectra and detector simulation. We consider a generic model with the CP violating Higgs tensor couplings to gauge bosons. We introduce a new variable describing angular distributions of the secondary WW and ZZ decay products which is very sensitive to the CP properties of the Higgs-boson. Understanding of the detector performance turns out to be crucial, as the influence of the acceptance corrections is similar to the effects of CP violation. From the combined measurement of invariant mass distributions and various angular distributions the phase describing a CP violation can be determined to about 50 mrad after one year of Photon Collider running.
[ { "created": "Thu, 21 Oct 2004 12:14:18 GMT", "version": "v1" } ]
2007-05-23
[ [ "Niezurawski", "P.", "" ], [ "Zarnecki", "A. F.", "" ], [ "Krawczyk", "M.", "" ] ]
The model-independent determination of the Higgs-boson CP properties at the Photon Collider at TESLA has been studied in detail, for masses between 200 and 350 GeV, using realistic luminosity spectra and detector simulation. We consider a generic model with the CP violating Higgs tensor couplings to gauge bosons. We introduce a new variable describing angular distributions of the secondary WW and ZZ decay products which is very sensitive to the CP properties of the Higgs-boson. Understanding of the detector performance turns out to be crucial, as the influence of the acceptance corrections is similar to the effects of CP violation. From the combined measurement of invariant mass distributions and various angular distributions the phase describing a CP violation can be determined to about 50 mrad after one year of Photon Collider running.
2201.01754
Narayan Rana
Tommaso Armadillo, Roberto Bonciani, Simone Devoto, Narayan Rana, Alessandro Vicini
Two-loop mixed QCD-EW corrections to neutral current Drell-Yan
33 pages, 5 figures; Ancillary files attached; Version accepted for publication in JHEP
null
10.1007/JHEP05(2022)072
TIF-UNIMI-2022-1
hep-ph
http://creativecommons.org/licenses/by/4.0/
We present the two-loop mixed strong-electroweak virtual corrections to the neutral current Drell-Yan process and we provide, in ancillary files, the explicit formulae of the infrared-subtracted finite remainder. The final state collinear singularities are regularised by the lepton mass. The evaluation of all the relevant Feynman integrals, including those with up to two internal massive lines, has been worked out relying on analytical and semi-analytical techniques, in the case of complex-valued masses.
[ { "created": "Wed, 5 Jan 2022 18:34:57 GMT", "version": "v1" }, { "created": "Wed, 22 Jun 2022 14:21:53 GMT", "version": "v2" } ]
2022-06-23
[ [ "Armadillo", "Tommaso", "" ], [ "Bonciani", "Roberto", "" ], [ "Devoto", "Simone", "" ], [ "Rana", "Narayan", "" ], [ "Vicini", "Alessandro", "" ] ]
We present the two-loop mixed strong-electroweak virtual corrections to the neutral current Drell-Yan process and we provide, in ancillary files, the explicit formulae of the infrared-subtracted finite remainder. The final state collinear singularities are regularised by the lepton mass. The evaluation of all the relevant Feynman integrals, including those with up to two internal massive lines, has been worked out relying on analytical and semi-analytical techniques, in the case of complex-valued masses.
1106.5290
Xiang Liu
Dian-Yong Chen and Xiang Liu
Predicted charged charmonium-like structures in the hidden-charm dipion decay of higher charmonia
7 pages, 6 figures, 1 table. More discussions added. Accepted for publication in Phys. Rev. D
Phys.Rev.D84:034032,2011
10.1103/PhysRevD.84.034032
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we predict two charged charmonium-like structures close to the $D^\ast\bar{D}$ and $D^\ast\bar{D}^\ast$ thresholds, where the Initial Single Pion Emission mechanism is introduced in the hidden-charm dipion decays of higher charmonia $\psi(4040)$, $\psi(4160)$, $\psi(4415)$ and charmonium-like state Y(4260). We suggest BESIII to search for these structures in the $J/\psi\pi^+$, $\psi(2S)\pi^+$ and $h_b(1P)\pi^+$ invariant mass spectra of the $\psi(4040)$ decays into $J/\psi\pi^+\pi^-$, $\psi(2S)\pi^+\pi^-$ and $h_b(1P)\pi^+\pi^-$. In addition, the experimental search for these structures in the $J/\psi\pi^+$, $\psi(2S)\pi^+$ and $h_c(1P)\pi^+$ invariant mass spectra of the $\psi(4260)$ hidden-charm dipion decays will be accessible at Belle and BaBar.
[ { "created": "Mon, 27 Jun 2011 03:48:32 GMT", "version": "v1" }, { "created": "Thu, 30 Jun 2011 04:04:38 GMT", "version": "v2" }, { "created": "Thu, 4 Aug 2011 23:23:45 GMT", "version": "v3" } ]
2011-08-23
[ [ "Chen", "Dian-Yong", "" ], [ "Liu", "Xiang", "" ] ]
In this work, we predict two charged charmonium-like structures close to the $D^\ast\bar{D}$ and $D^\ast\bar{D}^\ast$ thresholds, where the Initial Single Pion Emission mechanism is introduced in the hidden-charm dipion decays of higher charmonia $\psi(4040)$, $\psi(4160)$, $\psi(4415)$ and charmonium-like state Y(4260). We suggest BESIII to search for these structures in the $J/\psi\pi^+$, $\psi(2S)\pi^+$ and $h_b(1P)\pi^+$ invariant mass spectra of the $\psi(4040)$ decays into $J/\psi\pi^+\pi^-$, $\psi(2S)\pi^+\pi^-$ and $h_b(1P)\pi^+\pi^-$. In addition, the experimental search for these structures in the $J/\psi\pi^+$, $\psi(2S)\pi^+$ and $h_c(1P)\pi^+$ invariant mass spectra of the $\psi(4260)$ hidden-charm dipion decays will be accessible at Belle and BaBar.
1905.03783
Enrique Munoz Tavera
Marcelo Loewe, Enrique Mu\~noz and Renato Zamora
Thermo-magnetic corrections to $\pi$-$\pi$ Scattering Lengths in the Linear Sigma Model
arXiv admin note: substantial text overlap with arXiv:1901.03256
Phys. Rev. D 100, 116006 (2019)
10.1103/PhysRevD.100.116006
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this article, we extend our previous study of the $\pi$-$\pi$ scattering lengths under the presence of an external magnetic field, including finite temperature effects. The novelty of this work is precisely the introduction of temperature into the discussion, and its interplay with the magnetic field. As in the previous article, we base our analysis in the linear sigma-model, and our calculations are exact within this context. Although the effects are comparatively small, it is interesting to remark that magnetic field and temperature display opposite effects over the scattering lengths.
[ { "created": "Wed, 8 May 2019 20:36:35 GMT", "version": "v1" } ]
2019-12-18
[ [ "Loewe", "Marcelo", "" ], [ "Muñoz", "Enrique", "" ], [ "Zamora", "Renato", "" ] ]
In this article, we extend our previous study of the $\pi$-$\pi$ scattering lengths under the presence of an external magnetic field, including finite temperature effects. The novelty of this work is precisely the introduction of temperature into the discussion, and its interplay with the magnetic field. As in the previous article, we base our analysis in the linear sigma-model, and our calculations are exact within this context. Although the effects are comparatively small, it is interesting to remark that magnetic field and temperature display opposite effects over the scattering lengths.
hep-ph/0508256
Mirco Cannoni
M.Cannoni, C.Carimalo, W.Da Silva, O.Panella
Testing SUSY models of lepton flavor violation at a photon collider
26 pages, 12 figures, Revtex4
Phys.Rev.D72:115004,2005; Erratum-ibid.D72:119907,2005
10.1103/PhysRevD.72.115004 10.1103/PhysRevD.72.119907
null
hep-ph
null
The loop level lepton flavor violating signals $\gamma \gamma \to \ell \ell' (\ell=e,\mu,\tau, \ell \neq \ell^\prime)$ are studied in a scenario of low-energy, R-parity conserving, supersymmetric seesaw mechanism within the context of a high energy photon collider. Lepton flavor violation is due to off diagonal elements in the left s-lepton mass matrix induced by renormalization group equations. The average slepton masses ${\widetilde{m}}$ and the off diagonal matrix elements $\Delta m$ are treated as model independent free phenomenological parameters in order to discover regions in the parameter space where the signal cross section may be observable. At the energies of the $\gamma \gamma$ option of the future high-energy linear collider the signal has a potentially large standard model background, and therefore particular attention is paid to the study of kinematical cuts in order to reduce the latter at an acceptable level. We find, for the ($e\tau$) channel, non-negligible fractions of the parameter space ($\delta_{LL}=\Delta m^2/\widetilde{m}^2 \gtrsim 10^{-1}$) where the statistical significance ($SS$) is $SS \gtrsim 3$.
[ { "created": "Wed, 24 Aug 2005 16:47:39 GMT", "version": "v1" } ]
2014-11-18
[ [ "Cannoni", "M.", "" ], [ "Carimalo", "C.", "" ], [ "Da Silva", "W.", "" ], [ "Panella", "O.", "" ] ]
The loop level lepton flavor violating signals $\gamma \gamma \to \ell \ell' (\ell=e,\mu,\tau, \ell \neq \ell^\prime)$ are studied in a scenario of low-energy, R-parity conserving, supersymmetric seesaw mechanism within the context of a high energy photon collider. Lepton flavor violation is due to off diagonal elements in the left s-lepton mass matrix induced by renormalization group equations. The average slepton masses ${\widetilde{m}}$ and the off diagonal matrix elements $\Delta m$ are treated as model independent free phenomenological parameters in order to discover regions in the parameter space where the signal cross section may be observable. At the energies of the $\gamma \gamma$ option of the future high-energy linear collider the signal has a potentially large standard model background, and therefore particular attention is paid to the study of kinematical cuts in order to reduce the latter at an acceptable level. We find, for the ($e\tau$) channel, non-negligible fractions of the parameter space ($\delta_{LL}=\Delta m^2/\widetilde{m}^2 \gtrsim 10^{-1}$) where the statistical significance ($SS$) is $SS \gtrsim 3$.
hep-ph/0305048
Stephanie Trine
S. Trine
Strong Anomalies in Kaon Decays
Latex, 2 pages. Talk presented at the 38th Rencontres de Moriond on Electroweak Interactions and Unified Theories, Les Arcs, France, March 15-22, 2003. To appear in the proceedings
null
null
null
hep-ph
null
We point to a potentially large contribution of the QCD trace anomaly to the isoscalar pion pair production in Kaon decays. This contribution arises from the long-distance evolution of a 7-dimensional quark-gluon operator generated by short-distance QCD corrections to the Delta_S = 1 Fermi Hamiltonian.
[ { "created": "Mon, 5 May 2003 16:29:09 GMT", "version": "v1" } ]
2007-05-23
[ [ "Trine", "S.", "" ] ]
We point to a potentially large contribution of the QCD trace anomaly to the isoscalar pion pair production in Kaon decays. This contribution arises from the long-distance evolution of a 7-dimensional quark-gluon operator generated by short-distance QCD corrections to the Delta_S = 1 Fermi Hamiltonian.
1009.2635
Ambar Ghosal
Biswajit Adhikary, Ambar Ghosal and Probir Roy
Baryon asymmetry from leptogenesis with four zero neutrino Yukawa textures
35 pages, no figure, Published Version
JCAP 1101:025,2011
10.1088/1475-7516/2011/01/025
SINP/APC/09/10/3
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The generation of the right amount of baryon asymmetry $\eta$ of the Universe from supersymmetric leptogenesis is studied within the type-I seesaw framework with three heavy singlet Majorana neutrinos $N_i\,\,(i = 1,2,3)$ and their superpartners. We assume the occurrence of four zeroes in the neutrino Yukawa coupling matrix $Y_\nu$, taken to be $\mu\tau$ symmetric, in the weak basis where $N_i$ (with real masses $M_i>0$) and the charged leptons $l_\alpha\,\, (\alpha = e,\mu,\tau)$ are mass diagonal. The quadrant of the single nontrivial phase, allowed in the corresponding light neutrino mass matrix $m_\nu$, gets fixed and additional constraints ensue from the requirement of matching $\eta$ with its observed value. Special attention is paid to flavor effects in the washout of the lepton asymmetry. We also comment on the role of small departures from high scale $\mu\tau$ symmetry due to RG evolution.
[ { "created": "Tue, 14 Sep 2010 12:31:41 GMT", "version": "v1" }, { "created": "Thu, 27 Jan 2011 10:39:48 GMT", "version": "v2" } ]
2011-01-28
[ [ "Adhikary", "Biswajit", "" ], [ "Ghosal", "Ambar", "" ], [ "Roy", "Probir", "" ] ]
The generation of the right amount of baryon asymmetry $\eta$ of the Universe from supersymmetric leptogenesis is studied within the type-I seesaw framework with three heavy singlet Majorana neutrinos $N_i\,\,(i = 1,2,3)$ and their superpartners. We assume the occurrence of four zeroes in the neutrino Yukawa coupling matrix $Y_\nu$, taken to be $\mu\tau$ symmetric, in the weak basis where $N_i$ (with real masses $M_i>0$) and the charged leptons $l_\alpha\,\, (\alpha = e,\mu,\tau)$ are mass diagonal. The quadrant of the single nontrivial phase, allowed in the corresponding light neutrino mass matrix $m_\nu$, gets fixed and additional constraints ensue from the requirement of matching $\eta$ with its observed value. Special attention is paid to flavor effects in the washout of the lepton asymmetry. We also comment on the role of small departures from high scale $\mu\tau$ symmetry due to RG evolution.
1209.4319
Giovanni Ossola
Pierpaolo Mastrolia, Edoardo Mirabella, Giovanni Ossola, Tiziano Peraro
Integrand Reduction for Two-Loop Scattering Amplitudes through Multivariate Polynomial Division
32 pages, 4 figures. v2: published version, text improved, new subsection 4.4 added
Phys. Rev. D 87, 085026 (2013)
10.1103/PhysRevD.87.085026
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe the application of a novel approach for the reduction of scattering amplitudes, based on multivariate polynomial division, which we have recently presented. This technique yields the complete integrand decomposition for arbitrary amplitudes, regardless of the number of loops. It allows for the determination of the residue at any multiparticle cut, whose knowledge is a mandatory prerequisite for applying the integrand-reduction procedure. By using the division modulo Groebner basis, we can derive a simple integrand recurrence relation that generates the multiparticle pole decomposition for integrands of arbitrary multiloop amplitudes. We apply the new reduction algorithm to the two-loop planar and nonplanar diagrams contributing to the five-point scattering amplitudes in N=4 super Yang-Mills and N=8 supergravity in four dimensions, whose numerator functions contain up to rank-two terms in the integration momenta. We determine all polynomial residues parametrizing the cuts of the corresponding topologies and subtopologies. We obtain the integral basis for the decomposition of each diagram from the polynomial form of the residues. Our approach is well suited for a seminumerical implementation, and its general mathematical properties provide an effective algorithm for the generalization of the integrand-reduction method to all orders in perturbation theory.
[ { "created": "Wed, 19 Sep 2012 18:20:57 GMT", "version": "v1" }, { "created": "Tue, 16 Jul 2013 08:15:45 GMT", "version": "v2" } ]
2013-07-17
[ [ "Mastrolia", "Pierpaolo", "" ], [ "Mirabella", "Edoardo", "" ], [ "Ossola", "Giovanni", "" ], [ "Peraro", "Tiziano", "" ] ]
We describe the application of a novel approach for the reduction of scattering amplitudes, based on multivariate polynomial division, which we have recently presented. This technique yields the complete integrand decomposition for arbitrary amplitudes, regardless of the number of loops. It allows for the determination of the residue at any multiparticle cut, whose knowledge is a mandatory prerequisite for applying the integrand-reduction procedure. By using the division modulo Groebner basis, we can derive a simple integrand recurrence relation that generates the multiparticle pole decomposition for integrands of arbitrary multiloop amplitudes. We apply the new reduction algorithm to the two-loop planar and nonplanar diagrams contributing to the five-point scattering amplitudes in N=4 super Yang-Mills and N=8 supergravity in four dimensions, whose numerator functions contain up to rank-two terms in the integration momenta. We determine all polynomial residues parametrizing the cuts of the corresponding topologies and subtopologies. We obtain the integral basis for the decomposition of each diagram from the polynomial form of the residues. Our approach is well suited for a seminumerical implementation, and its general mathematical properties provide an effective algorithm for the generalization of the integrand-reduction method to all orders in perturbation theory.
hep-ph/0207331
Rudnei O. Ramos
Sergio E. Joras and Rudnei O. Ramos
Noise and Dissipation During Preheating
13 pages, 2 eps figures, Revtex4
null
null
null
hep-ph astro-ph
null
We study the consequences of noise and dissipation for parametric resonance during preheating. The effective equations of motion for the inflaton and the radiation field are obtained and shown to present self-consistent noise and dissipation terms. The equations exhibit the usual parametric resonance phenomenon, allowing for exponential amplification of the radiation modes inside the instability bands. By focusing on the dimension of the border of those bands we explicitly show that they are fractal, indicating the strong dependence of the outcome in the initial conditions. The simultaneous effect of noise and dissipation to the fractality of the borders are then examined.
[ { "created": "Sat, 27 Jul 2002 00:16:11 GMT", "version": "v1" } ]
2007-05-23
[ [ "Joras", "Sergio E.", "" ], [ "Ramos", "Rudnei O.", "" ] ]
We study the consequences of noise and dissipation for parametric resonance during preheating. The effective equations of motion for the inflaton and the radiation field are obtained and shown to present self-consistent noise and dissipation terms. The equations exhibit the usual parametric resonance phenomenon, allowing for exponential amplification of the radiation modes inside the instability bands. By focusing on the dimension of the border of those bands we explicitly show that they are fractal, indicating the strong dependence of the outcome in the initial conditions. The simultaneous effect of noise and dissipation to the fractality of the borders are then examined.
hep-ph/0007348
Luca Girlanda
Luca Girlanda (Barcelona, Autonoma U.)
Relationship between the quark condensate and low-energy Pi-Pi observables beyond O(p^4)
contribution to LNF Spring School, Frascati, 15-20 May, 2000
null
null
null
hep-ph
null
The two-flavor Gell-Mann-Oakes-Renner ratio is expressed in terms of low-energy pi-pi observables including the O(p^6) double chiral logarithms, computed in Generalized Chiral Perturbation Theory. It is found that their contribution is important and tends to compensate the one from the single chiral logarithms.
[ { "created": "Sat, 29 Jul 2000 18:54:06 GMT", "version": "v1" } ]
2007-05-23
[ [ "Girlanda", "Luca", "", "Barcelona, Autonoma U." ] ]
The two-flavor Gell-Mann-Oakes-Renner ratio is expressed in terms of low-energy pi-pi observables including the O(p^6) double chiral logarithms, computed in Generalized Chiral Perturbation Theory. It is found that their contribution is important and tends to compensate the one from the single chiral logarithms.
1209.2559
Vladimir Braun M
V. M. Braun, A. N. Manashov, B. Pirnay
Finite-t and target mass corrections to deeply virtual Compton scattering
4 pages, 4 figures
Phys.Rev.Lett. 109 (2012) 242001
10.1103/PhysRevLett.109.242001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We carry out the first complete calculation of kinematic power corrections ~t/Q^2 and ~m^2/Q^2 to the helicity amplitudes of deeply virtual Compton scattering. This result removes an important source of uncertainties in the QCD predictions for intermediate momentum transfers Q^2 ~ 1-10 GeV^2 that are accessible in the existing and planned experiments. In particular the finite-t corrections are significant and must be taken into account in the data analysis.
[ { "created": "Wed, 12 Sep 2012 10:58:25 GMT", "version": "v1" } ]
2014-10-21
[ [ "Braun", "V. M.", "" ], [ "Manashov", "A. N.", "" ], [ "Pirnay", "B.", "" ] ]
We carry out the first complete calculation of kinematic power corrections ~t/Q^2 and ~m^2/Q^2 to the helicity amplitudes of deeply virtual Compton scattering. This result removes an important source of uncertainties in the QCD predictions for intermediate momentum transfers Q^2 ~ 1-10 GeV^2 that are accessible in the existing and planned experiments. In particular the finite-t corrections are significant and must be taken into account in the data analysis.
hep-ph/9712508
Gunther Piller
L. Mankiewicz, G. Piller and T. Weigl
Hard Leptoproduction of Charged Vector Mesons
8 pages, Latex
Phys.Rev. D59 (1999) 017501
10.1103/PhysRevD.59.017501
TUM/T39-97-33
hep-ph
null
We present an analysis of twist-2, leading order QCD amplitudes for hard exclusive leptoproduction of charged vector mesons. These processes are determined by nonforward parton distribution functions which are nondiagonal in quark flavor. We derive relations between flavor diagonal and nondiagonal distribution functions based on isospin symmetry. Furthermore, we discuss general features of rho^+ and rho^- production cross sections, and present estimates based on a simple model for nonforward distribution functions.
[ { "created": "Tue, 23 Dec 1997 16:18:31 GMT", "version": "v1" } ]
2009-10-30
[ [ "Mankiewicz", "L.", "" ], [ "Piller", "G.", "" ], [ "Weigl", "T.", "" ] ]
We present an analysis of twist-2, leading order QCD amplitudes for hard exclusive leptoproduction of charged vector mesons. These processes are determined by nonforward parton distribution functions which are nondiagonal in quark flavor. We derive relations between flavor diagonal and nondiagonal distribution functions based on isospin symmetry. Furthermore, we discuss general features of rho^+ and rho^- production cross sections, and present estimates based on a simple model for nonforward distribution functions.
1107.1312
Vivek Tiwari Kumar
Uma Shankar Gupta and Vivek Kumar Tiwari
Revisiting the Phase Structure of the Polyakov-quark-meson Model in the presence of Vacuum Fermion Fluctuation
19 pages, 17 figures
null
10.1103/PhysRevD.85.014010
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have considered the contribution of fermionic vacuum loop in the effective potential of Polyakov loop extended Quark Meson Model (PQM) for the two quark flavour case and explored the phase structure and thermodynamics of the resulting PQMVT model (Polyakov Quark Meson Model with Vacuum Term) in detail at non zero as well as zero chemical potential. The temperature variations of order parameters and their derivatives have been calculated and the phase diagram together with the location of critical end point (CEP) has been obtained in $\mu$, and $T$ plane in both the models PQMVT and PQM. The PQMVT model analysis has been compared with the calculations in PQM model in order to bring out the effect of fermionic vacuum term on the physical observables. We notice that the critical end point (CEP) which is located near the temperature axis at ($\mu=81.0$, $T = 167$ MeV) in the PQM model gets shifted close to the chemical potential axis at ($\mu_{CEP}=294.7$, $T_{CEP}=84.0$ MeV) in the PQMVT model calculations of the phase diagram. Since it emerges from a background of second order transition in the chiral limit of massless quarks, the crossover occurring at $\mu$ = 0 in PQMVT model for the realistic case of explicitly broken chiral symmetry, has been identified as quite a soft and smooth transition. We have presented and compared the results for temperature variations of thermodynamic observables at zero and different non-zero quark chemical potentials. It is noticed that the presence of fermionic vacuum term in the effective potential leads to a smoother and slower temperature variation of thermodynamic quantities.
[ { "created": "Thu, 7 Jul 2011 07:53:46 GMT", "version": "v1" } ]
2013-05-30
[ [ "Gupta", "Uma Shankar", "" ], [ "Tiwari", "Vivek Kumar", "" ] ]
We have considered the contribution of fermionic vacuum loop in the effective potential of Polyakov loop extended Quark Meson Model (PQM) for the two quark flavour case and explored the phase structure and thermodynamics of the resulting PQMVT model (Polyakov Quark Meson Model with Vacuum Term) in detail at non zero as well as zero chemical potential. The temperature variations of order parameters and their derivatives have been calculated and the phase diagram together with the location of critical end point (CEP) has been obtained in $\mu$, and $T$ plane in both the models PQMVT and PQM. The PQMVT model analysis has been compared with the calculations in PQM model in order to bring out the effect of fermionic vacuum term on the physical observables. We notice that the critical end point (CEP) which is located near the temperature axis at ($\mu=81.0$, $T = 167$ MeV) in the PQM model gets shifted close to the chemical potential axis at ($\mu_{CEP}=294.7$, $T_{CEP}=84.0$ MeV) in the PQMVT model calculations of the phase diagram. Since it emerges from a background of second order transition in the chiral limit of massless quarks, the crossover occurring at $\mu$ = 0 in PQMVT model for the realistic case of explicitly broken chiral symmetry, has been identified as quite a soft and smooth transition. We have presented and compared the results for temperature variations of thermodynamic observables at zero and different non-zero quark chemical potentials. It is noticed that the presence of fermionic vacuum term in the effective potential leads to a smoother and slower temperature variation of thermodynamic quantities.
2103.15861
Panagiotis Stylianou
Supratim Das Bakshi, Joydeep Chakrabortty, Christoph Englert, Michael Spannowsky and Panagiotis Stylianou
Landscaping CP-violating BSM scenarios
22 pages, 6 figures, 1 table; v2 accepted by NPB, 7 figures, 3 tables
null
10.1016/j.nuclphysb.2022.115676
IPPP/20/90
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a wide range of UV scenarios with the aim of informing searches for CP violation at the TeV scale using effective field theory techniques. We demonstrate that broad theoretical assumptions about the nature of UV dynamics responsible for CP violation map out a small subset of relevant operators at the TeV scale. Concretely, this will allow us to reduce the number of free parameters that need to be considered in experimental investigations, thus enhancing analyses' sensitivities. In parallel, reflecting the UV dynamics' Wilson coefficient hierarchy will enable a streamlined theoretical interpretation of such analyses in the future. We demonstrate a minimal approach to analysing CP violation in this context using a Monte Carlo study of a combination of weak boson fusion Higgs and electroweak diboson production, which provide complementary information on the relevant EFT operators.
[ { "created": "Mon, 29 Mar 2021 18:12:08 GMT", "version": "v1" }, { "created": "Mon, 31 Jan 2022 16:54:28 GMT", "version": "v2" } ]
2022-02-09
[ [ "Bakshi", "Supratim Das", "" ], [ "Chakrabortty", "Joydeep", "" ], [ "Englert", "Christoph", "" ], [ "Spannowsky", "Michael", "" ], [ "Stylianou", "Panagiotis", "" ] ]
We consider a wide range of UV scenarios with the aim of informing searches for CP violation at the TeV scale using effective field theory techniques. We demonstrate that broad theoretical assumptions about the nature of UV dynamics responsible for CP violation map out a small subset of relevant operators at the TeV scale. Concretely, this will allow us to reduce the number of free parameters that need to be considered in experimental investigations, thus enhancing analyses' sensitivities. In parallel, reflecting the UV dynamics' Wilson coefficient hierarchy will enable a streamlined theoretical interpretation of such analyses in the future. We demonstrate a minimal approach to analysing CP violation in this context using a Monte Carlo study of a combination of weak boson fusion Higgs and electroweak diboson production, which provide complementary information on the relevant EFT operators.
2205.09777
Ioana Zelko
Ioana A. Zelko, Tommaso Treu, Kevork N. Abazajian, Daniel Gilman, Andrew J. Benson, Simon Birrer, Anna M. Nierenberg, Alexander Kusenko
Constraints on sterile neutrino models from strong gravitational lensing, Milky Way satellites, and Lyman-$\alpha$ forest
Published in Physical Review Letters (PRL); 10 pages, 3 figures
Phys. Rev. Lett. 129, 191301. Published 4 November 2022
10.1103/PhysRevLett.129.191301
null
hep-ph astro-ph.CO astro-ph.GA
http://creativecommons.org/licenses/by-nc-nd/4.0/
The nature of dark matter is one of the most important unsolved questions in science. Some dark matter candidates do not have sufficient nongravitational interactions to be probed in laboratory or accelerator experiments. It is thus important to develop astrophysical probes which can constrain or lead to a discovery of such candidates. We illustrate this using state-of-the-art measurements of strong gravitationally-lensed quasars to constrain four of the most popular sterile neutrino models, and also report the constraints for other independent methods that are comparable in procedure. First, we derive effective relations to describe the correspondence between the mass of a thermal relic warm dark matter particle and the mass of sterile neutrinos produced via Higgs decay and GUT-scale scenarios, in terms of large-scale structure and galaxy formation astrophysical effects. Second, we show that sterile neutrinos produced through the Higgs decay mechanism are allowed only for mass $>26$ keV, and GUT-scale scenario $>5.3$ keV. Third, we show that the single sterile neutrino model produced through active neutrino oscillations is allowed for mass $>92$ keV, and the 3 sterile neutrino minimal standard model ($\nu$MSM) for mass $>16$ keV. These are the most stringent experimental limits on these models.
[ { "created": "Thu, 19 May 2022 18:00:34 GMT", "version": "v1" }, { "created": "Tue, 18 Jul 2023 19:56:09 GMT", "version": "v2" } ]
2023-07-20
[ [ "Zelko", "Ioana A.", "" ], [ "Treu", "Tommaso", "" ], [ "Abazajian", "Kevork N.", "" ], [ "Gilman", "Daniel", "" ], [ "Benson", "Andrew J.", "" ], [ "Birrer", "Simon", "" ], [ "Nierenberg", "Anna M.", "" ], [ "Kusenko", "Alexander", "" ] ]
The nature of dark matter is one of the most important unsolved questions in science. Some dark matter candidates do not have sufficient nongravitational interactions to be probed in laboratory or accelerator experiments. It is thus important to develop astrophysical probes which can constrain or lead to a discovery of such candidates. We illustrate this using state-of-the-art measurements of strong gravitationally-lensed quasars to constrain four of the most popular sterile neutrino models, and also report the constraints for other independent methods that are comparable in procedure. First, we derive effective relations to describe the correspondence between the mass of a thermal relic warm dark matter particle and the mass of sterile neutrinos produced via Higgs decay and GUT-scale scenarios, in terms of large-scale structure and galaxy formation astrophysical effects. Second, we show that sterile neutrinos produced through the Higgs decay mechanism are allowed only for mass $>26$ keV, and GUT-scale scenario $>5.3$ keV. Third, we show that the single sterile neutrino model produced through active neutrino oscillations is allowed for mass $>92$ keV, and the 3 sterile neutrino minimal standard model ($\nu$MSM) for mass $>16$ keV. These are the most stringent experimental limits on these models.
2102.09725
Robert Schabinger
Bakul Agarwal, Andreas von Manteuffel, Erik Panzer, and Robert M. Schabinger
Four-loop collinear anomalous dimensions in QCD and $\mathcal{N} = 4$ super Yang-Mills
10 pages, 1 figure, ancillary files with results
null
10.1016/j.physletb.2021.136503
MSUHEP-21-006
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the collinear anomalous dimensions in massless four-loop QCD and $\mathcal{N} = 4$ supersymmetric Yang-Mills theory from the infrared poles of vertex form factors. We give very precise numerical approximations and a conjecture for the complete analytic results in both models we consider.
[ { "created": "Fri, 19 Feb 2021 03:50:00 GMT", "version": "v1" } ]
2021-07-14
[ [ "Agarwal", "Bakul", "" ], [ "von Manteuffel", "Andreas", "" ], [ "Panzer", "Erik", "" ], [ "Schabinger", "Robert M.", "" ] ]
We calculate the collinear anomalous dimensions in massless four-loop QCD and $\mathcal{N} = 4$ supersymmetric Yang-Mills theory from the infrared poles of vertex form factors. We give very precise numerical approximations and a conjecture for the complete analytic results in both models we consider.
2401.00696
Arindam Das
Arindam Das and Yuta Orikasa
$Z^\prime$ induced forward dominant processes in $\mu$TRISTAN experiment
18 pages
Phys.Lett.B 851 (2024) 138577
10.1016/j.physletb.2024.138577
null
hep-ph hep-ex
http://creativecommons.org/publicdomain/zero/1.0/
General $U(1)$ extension of the Standard Model (SM) is a well motivated beyond the Standard Model(BSM) scenario where three generations of right handed neutrinos (RHNs) are introduced to cancel gauge and mixed gauge-gravity anomalies. After the $U(1)_X$ is broken, RHNs participate in the seesaw mechanism to generate light neutrino masses satisfying neutrino oscillation data. In addition to that, a neutral gauge boson $Z^\prime$ is evolved which interacts with the left and right handed fermions differently manifesting chiral nature of the model which could be probed in future collider experiments. As a result, if we consider $\mu^+ e^-$ and $\mu^+ \mu^+$ collisions in $\mu$TRISTAN experiment $Z^\prime$ mediated $2\to2$ scattering will appear in $t-$ and $u-$channels depending on the initial and final states being accompanied by the photon and $Z$ mediated interactions. This will result well motivated resulting forward dominant scenarios giving rise to sizable left-right asymmetry. Estimating constrains on general $U(1)$ coupling from LEP-II and LHC for different $U(1)_X$ charges, we calculate differential and integrated scattering cross section and left-right asymmetry for $\mu^+ e^- \to \mu^+ e^-$ and $\mu^+ \mu^+ \to \mu^+ \mu^+$ processes which could be probed at $\mu$TRISTAN experiment further enlightening the interaction between $Z^\prime$ and charged leptons and the $U(1)_X$ breaking scale.
[ { "created": "Mon, 1 Jan 2024 08:19:21 GMT", "version": "v1" }, { "created": "Tue, 16 Apr 2024 04:19:49 GMT", "version": "v2" } ]
2024-04-17
[ [ "Das", "Arindam", "" ], [ "Orikasa", "Yuta", "" ] ]
General $U(1)$ extension of the Standard Model (SM) is a well motivated beyond the Standard Model(BSM) scenario where three generations of right handed neutrinos (RHNs) are introduced to cancel gauge and mixed gauge-gravity anomalies. After the $U(1)_X$ is broken, RHNs participate in the seesaw mechanism to generate light neutrino masses satisfying neutrino oscillation data. In addition to that, a neutral gauge boson $Z^\prime$ is evolved which interacts with the left and right handed fermions differently manifesting chiral nature of the model which could be probed in future collider experiments. As a result, if we consider $\mu^+ e^-$ and $\mu^+ \mu^+$ collisions in $\mu$TRISTAN experiment $Z^\prime$ mediated $2\to2$ scattering will appear in $t-$ and $u-$channels depending on the initial and final states being accompanied by the photon and $Z$ mediated interactions. This will result well motivated resulting forward dominant scenarios giving rise to sizable left-right asymmetry. Estimating constrains on general $U(1)$ coupling from LEP-II and LHC for different $U(1)_X$ charges, we calculate differential and integrated scattering cross section and left-right asymmetry for $\mu^+ e^- \to \mu^+ e^-$ and $\mu^+ \mu^+ \to \mu^+ \mu^+$ processes which could be probed at $\mu$TRISTAN experiment further enlightening the interaction between $Z^\prime$ and charged leptons and the $U(1)_X$ breaking scale.