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1307.0406
Thomas Heinzl
Thomas Heinzl and Anton Ilderton
Corrections to Laser Electron Thomson Scattering
5 pages, 1 figure; updated version of contribution to 2012 Annual Report, Central Laser Facility (CLF), Rutherford-Appleton Laboratory, UK
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss classical and quantum corrections to Thomson scattering between an electron and a laser. For radiation reaction, nonlinear, and quantum effects we identify characteristic dimensionless parameters in terms of which we determine the leading order correction terms.
[ { "created": "Mon, 1 Jul 2013 15:26:06 GMT", "version": "v1" } ]
2013-07-02
[ [ "Heinzl", "Thomas", "" ], [ "Ilderton", "Anton", "" ] ]
We discuss classical and quantum corrections to Thomson scattering between an electron and a laser. For radiation reaction, nonlinear, and quantum effects we identify characteristic dimensionless parameters in terms of which we determine the leading order correction terms.
1905.11463
Li Lin Yang
Yuxuan Wang, Xiaofeng Xu, Li Lin Yang
Two-loop triangle integrals with 4 scales for the $HZV$ vertex
5 pages, 4 figures
Phys. Rev. D 100, 071502 (2019)
10.1103/PhysRevD.100.071502
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate analytically the two-loop triangle integrals entering the $\mathcal{O}(\alpha\alpha_s)$ corrections to the $HZV$ vertex with $V=Z^*,\gamma^*$ using the method of differential equations. Our result provides a prototype to study the analytic properties of multi-loop multi-scale Feynman integrals, and also allows fast numeric evaluation for phenomenological studies. We apply our results to the leptonic decay of the Higgs boson and to $ZH$ production at electron-positron colliders. Besides the top quark loop, we include also the bottom quark loop contributions, whose evaluation takes a lot of time using purely numeric methods, but is very efficient with our analytic results.
[ { "created": "Mon, 27 May 2019 19:21:21 GMT", "version": "v1" } ]
2019-10-23
[ [ "Wang", "Yuxuan", "" ], [ "Xu", "Xiaofeng", "" ], [ "Yang", "Li Lin", "" ] ]
We calculate analytically the two-loop triangle integrals entering the $\mathcal{O}(\alpha\alpha_s)$ corrections to the $HZV$ vertex with $V=Z^*,\gamma^*$ using the method of differential equations. Our result provides a prototype to study the analytic properties of multi-loop multi-scale Feynman integrals, and also allows fast numeric evaluation for phenomenological studies. We apply our results to the leptonic decay of the Higgs boson and to $ZH$ production at electron-positron colliders. Besides the top quark loop, we include also the bottom quark loop contributions, whose evaluation takes a lot of time using purely numeric methods, but is very efficient with our analytic results.
hep-ph/0303130
Athanasios Lahanas
A. B. Lahanas (Athens U), D. V. Nanopoulos (Texas A&M U)
WMAPing out Supersymmetric Dark Matter and Phenomenology
12 pages LaTeX, 5 eps figures included, references added
Phys.Lett.B568:55-62,2003
10.1016/S0370-2693(03)00832-3
MIFP-03-06, ACT-03-02
hep-ph astro-ph
null
The recent WMAP data provide a rather restricted range of the Cold Dark Matter (CDM) density $ \Omega_{CDM} h^2 $ of unprecedented accuracy. We combine these new data along with data from BNL E821 experiment measuring $ {(g_{\mu}-2)}$, $ $the {$b\goes s \gamma$} branching ratio and the light Higgs boson mass bound from LEP, to update our analysis of the allowed boundaries in the parameter space of the Constrained Minimal Supersymmetric Standard Model (CMSSM). The prospects of measuring Supersymmetry at LHC look like a very safe bet, and the potential of discovering SUSY particles at a $ \sqrt{s} = 1.1 \mathrm{TeV} $ linear collider is enhanced considerably. The implications for Dark Matter direct searches are also discussed.
[ { "created": "Fri, 14 Mar 2003 20:51:22 GMT", "version": "v1" }, { "created": "Tue, 1 Apr 2003 17:11:47 GMT", "version": "v2" } ]
2008-11-26
[ [ "Lahanas", "A. B.", "", "Athens U" ], [ "Nanopoulos", "D. V.", "", "Texas A&M U" ] ]
The recent WMAP data provide a rather restricted range of the Cold Dark Matter (CDM) density $ \Omega_{CDM} h^2 $ of unprecedented accuracy. We combine these new data along with data from BNL E821 experiment measuring $ {(g_{\mu}-2)}$, $ $the {$b\goes s \gamma$} branching ratio and the light Higgs boson mass bound from LEP, to update our analysis of the allowed boundaries in the parameter space of the Constrained Minimal Supersymmetric Standard Model (CMSSM). The prospects of measuring Supersymmetry at LHC look like a very safe bet, and the potential of discovering SUSY particles at a $ \sqrt{s} = 1.1 \mathrm{TeV} $ linear collider is enhanced considerably. The implications for Dark Matter direct searches are also discussed.
0802.2215
Andrea Ferroglia
R. Bonciani, A. Ferroglia, and A.A. Penin
Calculation of the Two-Loop Heavy-Flavor Contribution to Bhabha Scattering
43 pages, 8 figures; added references
JHEP0802:080,2008
10.1088/1126-6708/2008/02/080
ALBERTA-THY-24-07, IFIC/07-77, ZU-TH 31/07
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe in detail the calculation of the two-loop corrections to the QED Bhabha scattering cross section due to the vacuum polarization by heavy fermions. Our approach eliminates one mass scale from the most challenging part of the calculation and allows us to obtain the corrections in a closed analytical form. The result is valid for arbitrary values of the heavy fermion mass and the Mandelstam invariants, as long as s,t,u >> m_e^2.
[ { "created": "Fri, 15 Feb 2008 14:48:08 GMT", "version": "v1" }, { "created": "Mon, 31 Mar 2008 12:41:49 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bonciani", "R.", "" ], [ "Ferroglia", "A.", "" ], [ "Penin", "A. A.", "" ] ]
We describe in detail the calculation of the two-loop corrections to the QED Bhabha scattering cross section due to the vacuum polarization by heavy fermions. Our approach eliminates one mass scale from the most challenging part of the calculation and allows us to obtain the corrections in a closed analytical form. The result is valid for arbitrary values of the heavy fermion mass and the Mandelstam invariants, as long as s,t,u >> m_e^2.
2002.12630
Matthew McCullough
Timothy Cohen, Nathaniel Craig, Seth Koren, Matthew McCullough and Joseph Tooby-Smith
Supersoft Stops
5 pages
Phys. Rev. Lett. 125, 151801 (2020)
10.1103/PhysRevLett.125.151801
CERN-TH-2020-013
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a supersymmetric (SUSY) theory, the IR-contributions to the Higgs mass are calculable below the mediation scale $\Lambda_{\text{UV}}$ in terms of the IR field content and parameters. However, logarithmic sensitivity to physics at $\Lambda_{\text{UV}}$ remains. In this work we present a first example of a framework, dictated by symmetries, to supersoften these logarithms from the matter sector. The result is a model with finite, IR-calculable corrections to the Higgs mass. This requires the introduction of new fields -- the `lumberjacks' -- whose role is to screen the UV-sensitive logs. These models have considerably reduced fine-tuning, by more than an order of magnitude for high scale supersymmetry. This impacts interpretations of the natural parameter space, suggesting it may be premature to declare a naturalness crisis for high-scale SUSY.
[ { "created": "Fri, 28 Feb 2020 10:20:04 GMT", "version": "v1" } ]
2020-10-14
[ [ "Cohen", "Timothy", "" ], [ "Craig", "Nathaniel", "" ], [ "Koren", "Seth", "" ], [ "McCullough", "Matthew", "" ], [ "Tooby-Smith", "Joseph", "" ] ]
In a supersymmetric (SUSY) theory, the IR-contributions to the Higgs mass are calculable below the mediation scale $\Lambda_{\text{UV}}$ in terms of the IR field content and parameters. However, logarithmic sensitivity to physics at $\Lambda_{\text{UV}}$ remains. In this work we present a first example of a framework, dictated by symmetries, to supersoften these logarithms from the matter sector. The result is a model with finite, IR-calculable corrections to the Higgs mass. This requires the introduction of new fields -- the `lumberjacks' -- whose role is to screen the UV-sensitive logs. These models have considerably reduced fine-tuning, by more than an order of magnitude for high scale supersymmetry. This impacts interpretations of the natural parameter space, suggesting it may be premature to declare a naturalness crisis for high-scale SUSY.
0804.0717
Stefan Antusch
Stefan Antusch, Martin Spinrath
Quark and lepton masses at the GUT scale including SUSY threshold corrections
22 pages, 5 figures; comments added, figure 5 extended; version to appear in Phys. Rev. D
Phys.Rev.D78:075020,2008
10.1103/PhysRevD.78.075020
MPP-2008-31
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the effect of supersymmetric (SUSY) threshold corrections on the values of the running quark and charged lepton masses at the GUT scale within the large $\tan\beta$ regime of the MSSM. In addition to the typically dominant SUSY QCD contributions for the quarks, we also include the electroweak contributions for quarks and leptons and show that they can have significant effects. We provide the GUT scale ranges of quark and charged lepton Yukawa couplings as well as of the ratios $m_\mu/m_s$, $m_e/m_d$, $y_\tau/y_b$ and $y_t/y_b$ for three example ranges of SUSY parameters. We discuss how the enlarged ranges due to threshold effects might open up new possibilities for constructing GUT models of fermion masses and mixings.
[ { "created": "Fri, 4 Apr 2008 12:51:13 GMT", "version": "v1" }, { "created": "Mon, 6 Oct 2008 15:20:13 GMT", "version": "v2" } ]
2008-11-26
[ [ "Antusch", "Stefan", "" ], [ "Spinrath", "Martin", "" ] ]
We investigate the effect of supersymmetric (SUSY) threshold corrections on the values of the running quark and charged lepton masses at the GUT scale within the large $\tan\beta$ regime of the MSSM. In addition to the typically dominant SUSY QCD contributions for the quarks, we also include the electroweak contributions for quarks and leptons and show that they can have significant effects. We provide the GUT scale ranges of quark and charged lepton Yukawa couplings as well as of the ratios $m_\mu/m_s$, $m_e/m_d$, $y_\tau/y_b$ and $y_t/y_b$ for three example ranges of SUSY parameters. We discuss how the enlarged ranges due to threshold effects might open up new possibilities for constructing GUT models of fermion masses and mixings.
0810.2439
Abdelhak Djouadi
Abdelhak Djouadi
The Higgs sector of supersymmetric theories and the implications for high-energy colliders
50 pages. To be published in "Supersymmetry on the Eve of the LHC" a special volume of European Physical Journal C in memory of Julius Wess. v2: references and comments added, some typos corrected
Eur.Phys.J.C59:389-426,2009
10.1140/epjc/s10052-008-0788-y
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One of the main motivations for low energy supersymmetric theories is their ability to address the hierarchy and naturalness problems in the Higgs sector of the Standard Model. In these theories, at least two doublets of scalar fields are required to break the electroweak symmetry and to generate the masses of the elementary particles, resulting in a rather rich Higgs spectrum. The search for the Higgs bosons of Supersymmetry and the determination of their basic properties is one of the major goals of high--energy colliders and, in particular, the LHC which will soon start operation. We review the salient features of the Higgs sector of the Minimal Supersymmetric Standard Model and of some of its extensions and summarize the prospects for probing them at the LHC and at the future ILC.
[ { "created": "Tue, 14 Oct 2008 12:29:44 GMT", "version": "v1" }, { "created": "Thu, 16 Oct 2008 13:50:17 GMT", "version": "v2" } ]
2010-04-21
[ [ "Djouadi", "Abdelhak", "" ] ]
One of the main motivations for low energy supersymmetric theories is their ability to address the hierarchy and naturalness problems in the Higgs sector of the Standard Model. In these theories, at least two doublets of scalar fields are required to break the electroweak symmetry and to generate the masses of the elementary particles, resulting in a rather rich Higgs spectrum. The search for the Higgs bosons of Supersymmetry and the determination of their basic properties is one of the major goals of high--energy colliders and, in particular, the LHC which will soon start operation. We review the salient features of the Higgs sector of the Minimal Supersymmetric Standard Model and of some of its extensions and summarize the prospects for probing them at the LHC and at the future ILC.
hep-ph/0402279
Jose Illana
J.I. Illana, M. Masip and D. Meloni
Cosmogenic neutrinos and signals of TeV gravity in air showers and neutrino telescopes
10 pages, 1 figure; version to appear in Phys. Rev. Lett
Phys.Rev.Lett. 93 (2004) 151102
10.1103/PhysRevLett.93.151102
CAFPE-31/04, UG-FT-161/04
hep-ph astro-ph
null
The existence of extra dimensions allows the possibility that the fundamental scale of gravity is at the TeV. If that is the case, gravity could dominate the interactions of ultra-high energy cosmic rays. In particular, the production of microscopic black holes by cosmogenic neutrinos has been estimated in a number of papers. We consider here gravity-mediated interactions at larger distances, where they can be calculated in the eikonal approximation. We show that for the expected flux of cosmogenic neutrinos these elastic processes give a stronger signal than black hole production in neutrino telescopes. Taking the bounds on the higher dimensional Planck mass M_D (D=4+n) from current air shower experiments, for n=2 (6) elastic collisions could produce up to 118 (34) events per year at IceCube. On the other hand, the absence of any signal would imply a bound of M_D>~5 TeV.
[ { "created": "Thu, 26 Feb 2004 18:09:13 GMT", "version": "v1" }, { "created": "Tue, 31 Aug 2004 09:56:06 GMT", "version": "v2" } ]
2009-11-10
[ [ "Illana", "J. I.", "" ], [ "Masip", "M.", "" ], [ "Meloni", "D.", "" ] ]
The existence of extra dimensions allows the possibility that the fundamental scale of gravity is at the TeV. If that is the case, gravity could dominate the interactions of ultra-high energy cosmic rays. In particular, the production of microscopic black holes by cosmogenic neutrinos has been estimated in a number of papers. We consider here gravity-mediated interactions at larger distances, where they can be calculated in the eikonal approximation. We show that for the expected flux of cosmogenic neutrinos these elastic processes give a stronger signal than black hole production in neutrino telescopes. Taking the bounds on the higher dimensional Planck mass M_D (D=4+n) from current air shower experiments, for n=2 (6) elastic collisions could produce up to 118 (34) events per year at IceCube. On the other hand, the absence of any signal would imply a bound of M_D>~5 TeV.
1411.2588
Susanne Westhoff
Tao Han, Joshua Sayre, Susanne Westhoff
Top-Quark Initiated Processes at High-Energy Hadron Colliders
30 pages, 9 figures, 1 table, matches version published in JHEP
Journal of High Energy Physics, April 2015, 2015:145
10.1007/JHEP04(2015)145
PITT-PACC-1405
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In hadronic collisions at high energies, the top-quark may be treated as a parton inside a hadron. Top-quark initiated processes become increasingly important since the top-quark luminosity can reach a few percent of the bottom-quark luminosity. In the production of a heavy particle $H$ with mass $m_H > m_t$, treating the top-quark as a parton allows us to resum large logarithms $\log(m_{H}^{2}/m_{t}^{2}$) arising from collinear splitting in the initial state. We quantify the effect of collinear resummation at the 14-TeV LHC and a future 100-TeV hadron collider, focusing on the top-quark open-flavor process $gg\to t\bar t H$ in comparison with $t\bar t \to H$ and $tg\rightarrow tH$ at the leading order (LO) in QCD. We employ top-quark parton distribution functions with appropriate collinear subtraction and power counting. We find that (1) Collinear resummation enhances the inclusive production of a heavy particle with $m_H\approx$ 5 TeV (0.5 TeV) by more than a factor of two compared to the open-flavor process at a 100-TeV (14-TeV) collider; (2) Top-quark mass effects are important for scales $m_H$ near the top-quark threshold, where the cross section is largest. We advocate a modification of the ACOT factorization scheme, dubbed m-ACOT, to consistently treat heavy-quark masses in hadronic collisions; (3) The scale uncertainty of the total cross section in m-ACOT is of about 20 percent at the LO. While a higher-order calculation is indispensable for a precise prediction, the LO cross section is well described by the process $t\bar t\to H$ using an effective factorization scale significantly lower than $m_H$. We illustrate our results by the example of a heavy spin-0 particle. Our main results also apply to the production of particles with spin-1 and 2.
[ { "created": "Mon, 10 Nov 2014 21:00:00 GMT", "version": "v1" }, { "created": "Tue, 9 Jun 2015 21:14:24 GMT", "version": "v2" } ]
2015-06-11
[ [ "Han", "Tao", "" ], [ "Sayre", "Joshua", "" ], [ "Westhoff", "Susanne", "" ] ]
In hadronic collisions at high energies, the top-quark may be treated as a parton inside a hadron. Top-quark initiated processes become increasingly important since the top-quark luminosity can reach a few percent of the bottom-quark luminosity. In the production of a heavy particle $H$ with mass $m_H > m_t$, treating the top-quark as a parton allows us to resum large logarithms $\log(m_{H}^{2}/m_{t}^{2}$) arising from collinear splitting in the initial state. We quantify the effect of collinear resummation at the 14-TeV LHC and a future 100-TeV hadron collider, focusing on the top-quark open-flavor process $gg\to t\bar t H$ in comparison with $t\bar t \to H$ and $tg\rightarrow tH$ at the leading order (LO) in QCD. We employ top-quark parton distribution functions with appropriate collinear subtraction and power counting. We find that (1) Collinear resummation enhances the inclusive production of a heavy particle with $m_H\approx$ 5 TeV (0.5 TeV) by more than a factor of two compared to the open-flavor process at a 100-TeV (14-TeV) collider; (2) Top-quark mass effects are important for scales $m_H$ near the top-quark threshold, where the cross section is largest. We advocate a modification of the ACOT factorization scheme, dubbed m-ACOT, to consistently treat heavy-quark masses in hadronic collisions; (3) The scale uncertainty of the total cross section in m-ACOT is of about 20 percent at the LO. While a higher-order calculation is indispensable for a precise prediction, the LO cross section is well described by the process $t\bar t\to H$ using an effective factorization scale significantly lower than $m_H$. We illustrate our results by the example of a heavy spin-0 particle. Our main results also apply to the production of particles with spin-1 and 2.
1109.0302
D.N. Triantafyllopoulos
E. Iancu, D. N. Triantafyllopoulos
Higher-point correlations from the JIMWLK evolution
v3: 22 pages, 1 figure, minor corrections, published in JHEP
JHEP 1111:105,2011
10.1007/JHEP11(2011)105
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop a new approximation scheme aiming at extracting higher-point correlation functions from the JIMWLK evolution, in the limit where the number of colors is large. Namely, we show that by exploiting the structure of the 'virtual' terms in the Balitsky-JIMWLK equations, one can derive functional relations expressing arbitrary n-point functions of the Wilson lines in terms of the 2-point function (the scattering amplitude for a color dipole). These approximations are correct not only in the regime of strong scattering, where the evolution is indeed controlled by the 'virtual' terms, but also in the regime of weak scattering, where they reduce to the corresponding BFKL solutions. This last feature follows from the fact that the JIMWLK Hamiltonian is a linear combination of the pieces responsible for the 'real' and 'virtual' terms, respectively. We apply this scheme to two examples: the 'color quadrupole' (the 4-point function of the Wilson lines which enters the cross-section for the production of a pair of jets at forward rapidities) and the 'color sextupole' (the 6-point function). For particular configurations of the quadrupole, our general formula reduces to relatively simple expressions that have been previously proposed on the basis of the McLerran-Venugopalan model and which were recently shown to agree quite well with exact, numerical, solutions to the JIMWLK equation.
[ { "created": "Thu, 1 Sep 2011 20:55:43 GMT", "version": "v1" }, { "created": "Wed, 7 Sep 2011 14:51:35 GMT", "version": "v2" }, { "created": "Fri, 23 Mar 2012 22:57:31 GMT", "version": "v3" } ]
2012-03-27
[ [ "Iancu", "E.", "" ], [ "Triantafyllopoulos", "D. N.", "" ] ]
We develop a new approximation scheme aiming at extracting higher-point correlation functions from the JIMWLK evolution, in the limit where the number of colors is large. Namely, we show that by exploiting the structure of the 'virtual' terms in the Balitsky-JIMWLK equations, one can derive functional relations expressing arbitrary n-point functions of the Wilson lines in terms of the 2-point function (the scattering amplitude for a color dipole). These approximations are correct not only in the regime of strong scattering, where the evolution is indeed controlled by the 'virtual' terms, but also in the regime of weak scattering, where they reduce to the corresponding BFKL solutions. This last feature follows from the fact that the JIMWLK Hamiltonian is a linear combination of the pieces responsible for the 'real' and 'virtual' terms, respectively. We apply this scheme to two examples: the 'color quadrupole' (the 4-point function of the Wilson lines which enters the cross-section for the production of a pair of jets at forward rapidities) and the 'color sextupole' (the 6-point function). For particular configurations of the quadrupole, our general formula reduces to relatively simple expressions that have been previously proposed on the basis of the McLerran-Venugopalan model and which were recently shown to agree quite well with exact, numerical, solutions to the JIMWLK equation.
1109.0460
Lisheng Geng
M. Altenbuchinger, L. S. Geng, and W. Weise
SU(3) breaking corrections to the $D$, $D^*$, $B$, and $B^*$ decay constants
11 pages, 2 figures, 2 tables; typos corrected, clarifications added, results remaining unchanged
Physics Letters B 713, 453-456 (2012)
10.1016/j.physletb.2012.06.025
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on a first next-to-next-to-leading order calculation of the decay constants of the $D$ ($D^*$) and $B$ ($B^*$) mesons using a covariant formulation of chiral perturbation theory. It is shown that, using the state-of-the-art lattice QCD results on $f_{D_s}/f_D$ as input, one can predict quantitatively the ratios of $f_{D_s^*}/f_{D^*}$, $f_{B_s}/f_B$, and $f_{B^*_s}/f_{B^*}$ taking into account heavy-quark spin-flavor symmetry breaking effects on the relevant low-energy constants. The predicted relations between these ratios, $f_{D^*_s}/f_{D^*}<f_{D_s}/f_D$ and $f_{B_s}/f_B>f_{D_s}/f_D$, and their light-quark mass dependence should be testable in future lattice QCD simulations, providing a stringent test of our understanding of heavy quark spin-flavor symmetry, chiral symmetry and their breaking patterns.
[ { "created": "Fri, 2 Sep 2011 14:48:18 GMT", "version": "v1" }, { "created": "Tue, 10 Jul 2012 01:55:24 GMT", "version": "v2" } ]
2012-07-11
[ [ "Altenbuchinger", "M.", "" ], [ "Geng", "L. S.", "" ], [ "Weise", "W.", "" ] ]
We report on a first next-to-next-to-leading order calculation of the decay constants of the $D$ ($D^*$) and $B$ ($B^*$) mesons using a covariant formulation of chiral perturbation theory. It is shown that, using the state-of-the-art lattice QCD results on $f_{D_s}/f_D$ as input, one can predict quantitatively the ratios of $f_{D_s^*}/f_{D^*}$, $f_{B_s}/f_B$, and $f_{B^*_s}/f_{B^*}$ taking into account heavy-quark spin-flavor symmetry breaking effects on the relevant low-energy constants. The predicted relations between these ratios, $f_{D^*_s}/f_{D^*}<f_{D_s}/f_D$ and $f_{B_s}/f_B>f_{D_s}/f_D$, and their light-quark mass dependence should be testable in future lattice QCD simulations, providing a stringent test of our understanding of heavy quark spin-flavor symmetry, chiral symmetry and their breaking patterns.
hep-ph/0108224
Anatoly Kotikov
V. G. Krivokhijine, A. V. Kotikov (JINR, Dubna)
A systematic study of QCD coupling constant from deep inelastic measurements
47 pages, 14 figures, latex
null
null
null
hep-ph
null
We reanalyze deep inelastic scattering data of BCDMS Collaboration by including proper cuts of ranges with large systematic errors. We perform also the fits of high statistic deep inelastic scattering data of BCDMS, SLAC, NM and BFP Collaborations taking the data separately and in combined way and find good agreement between these analyses. We extract the values of both the QCD coupling constant \alpha_s(M^2_Z) up to NLO level and of the power corrections to the structure function F_2. The fits of the combined data for the nonsinglet part of the structure function F_2 predict the coupling constant value \alpha_s(M^2_Z) = 0.1174 \pm 0.0007 (stat) \pm 0.0019 (syst) \pm 0.0010 (normalization) (or QCD parameter \Lambda^{(5)}_{MSbar} = 204 \pm 25 (total exper.err.) MeV). The fits of the combined data for both: the nonsinglet part and the singlet one, lead to the values \alpha_s(M^2_Z) = 0.1177 \pm 0.0007 (stat) \pm 0.0021 (syst) \pm 0.0009 (normalization) (or QCD parameter \Lambda^{(5)}_{MSbar} = 208 \pm 27 (total exper.err.) MeV). Both above values are in very good agreement with each other. We estimate theoretical uncertainties for \alpha_s(M^2_Z) as +0.0047 and -0.0057 from fits of the combine data, when complete singlet and nonsinglet Q^2 evolution is taken into account.
[ { "created": "Mon, 27 Aug 2001 16:38:39 GMT", "version": "v1" } ]
2007-05-23
[ [ "Krivokhijine", "V. G.", "", "JINR, Dubna" ], [ "Kotikov", "A. V.", "", "JINR, Dubna" ] ]
We reanalyze deep inelastic scattering data of BCDMS Collaboration by including proper cuts of ranges with large systematic errors. We perform also the fits of high statistic deep inelastic scattering data of BCDMS, SLAC, NM and BFP Collaborations taking the data separately and in combined way and find good agreement between these analyses. We extract the values of both the QCD coupling constant \alpha_s(M^2_Z) up to NLO level and of the power corrections to the structure function F_2. The fits of the combined data for the nonsinglet part of the structure function F_2 predict the coupling constant value \alpha_s(M^2_Z) = 0.1174 \pm 0.0007 (stat) \pm 0.0019 (syst) \pm 0.0010 (normalization) (or QCD parameter \Lambda^{(5)}_{MSbar} = 204 \pm 25 (total exper.err.) MeV). The fits of the combined data for both: the nonsinglet part and the singlet one, lead to the values \alpha_s(M^2_Z) = 0.1177 \pm 0.0007 (stat) \pm 0.0021 (syst) \pm 0.0009 (normalization) (or QCD parameter \Lambda^{(5)}_{MSbar} = 208 \pm 27 (total exper.err.) MeV). Both above values are in very good agreement with each other. We estimate theoretical uncertainties for \alpha_s(M^2_Z) as +0.0047 and -0.0057 from fits of the combine data, when complete singlet and nonsinglet Q^2 evolution is taken into account.
hep-ph/0009079
Geoff Oades
A. Gashi, E. Matsinos, G. C. Oades, G. Rasche and W. S.Woolcock
Electromagnetic corrections to the hadronic phase shifts in low energy pi+p elastic scattering
21 pages, 3 figures. Uses elsart.cls Accepted for publication in Nuclear Physics A
Nucl.Phys.A686:447-462,2001
10.1016/S0375-9474(00)00603-5
IFA-TH/2000.1
hep-ph nucl-th
null
We calculate the s and p-wave electromagnetic corrections which must be subtracted from the nuclear phase shifts obtained from the analysis of low energy pi+p elastic scattering data, in order to obtain hadronic phase shifts. We compare our results with earlier calculations and estimate the uncertainties in the corrections.
[ { "created": "Thu, 7 Sep 2000 09:56:54 GMT", "version": "v1" } ]
2008-11-26
[ [ "Gashi", "A.", "" ], [ "Matsinos", "E.", "" ], [ "Oades", "G. C.", "" ], [ "Rasche", "G.", "" ], [ "Woolcock", "W. S.", "" ] ]
We calculate the s and p-wave electromagnetic corrections which must be subtracted from the nuclear phase shifts obtained from the analysis of low energy pi+p elastic scattering data, in order to obtain hadronic phase shifts. We compare our results with earlier calculations and estimate the uncertainties in the corrections.
0910.3032
Graciela B. Gelmini
Graciela B. Gelmini
Relevance of Ion-Channeling for Direct DM Detection
Talk given at the TAUP 2009 conference, Rome, Italy, July 1-5 2009. 3 pages, 4 figures. jpconf.cls and jpconf11.clo files need to typeset the tex file
J.Phys.Conf.Ser.203:012042,2010
10.1088/1742-6596/203/1/012042
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The channeling of the recoiling nucleus in crystalline detectors after a WIMP collision would produce a larger scintillation or ionization signal in direct detection experiments than otherwise expected. I present estimates of the importance of this effect for the total direct detection rate and the daily modulation of the signal using analytic models produced in the 1960's and 70's to describe the effects of channeling and blocking in crystals.
[ { "created": "Fri, 16 Oct 2009 03:32:12 GMT", "version": "v1" } ]
2010-02-11
[ [ "Gelmini", "Graciela B.", "" ] ]
The channeling of the recoiling nucleus in crystalline detectors after a WIMP collision would produce a larger scintillation or ionization signal in direct detection experiments than otherwise expected. I present estimates of the importance of this effect for the total direct detection rate and the daily modulation of the signal using analytic models produced in the 1960's and 70's to describe the effects of channeling and blocking in crystals.
hep-ph/9908516
Athenasios Dedes
A. Dedes (RAL) and S. Moretti (RAL, Uppsala U.)
New Faces of Supersymmetry: effects of large phases on Higgs production
4 pages, 5 figures, title changed, version to appear in Phys.Rev.Lett
Phys.Rev.Lett. 84 (2000) 22-25
10.1103/PhysRevLett.84.22
RAL-TR-1999-064, TSL/ISV-99-0211
hep-ph hep-ex
null
If the soft Supersymmetry (SUSY) breaking masses and couplings are complex and cancelations do take place in the SUSY induced contributions to the fermionic Electric Dipole Moments (EDMs), then the CP-violating soft phases can drastically modify much of the known phenomenological pattern of the Minimal Supersymmetric Standard Model (MSSM). In particular, the squark loop content of the dominant Higgs production mechanism at the Large Hadron Collider (LHC), the gluon-gluon fusion mode, could be responsible of large corrections to the known cross sections.
[ { "created": "Tue, 31 Aug 1999 12:40:24 GMT", "version": "v1" }, { "created": "Thu, 2 Sep 1999 15:31:31 GMT", "version": "v2" }, { "created": "Fri, 12 Nov 1999 21:57:01 GMT", "version": "v3" } ]
2009-10-31
[ [ "Dedes", "A.", "", "RAL" ], [ "Moretti", "S.", "", "RAL, Uppsala U." ] ]
If the soft Supersymmetry (SUSY) breaking masses and couplings are complex and cancelations do take place in the SUSY induced contributions to the fermionic Electric Dipole Moments (EDMs), then the CP-violating soft phases can drastically modify much of the known phenomenological pattern of the Minimal Supersymmetric Standard Model (MSSM). In particular, the squark loop content of the dominant Higgs production mechanism at the Large Hadron Collider (LHC), the gluon-gluon fusion mode, could be responsible of large corrections to the known cross sections.
hep-ph/0604101
Tord Riemann
M. Czakon (Univ. Wuerzburg), J. Gluza (Univ. of Silesia), T. Riemann (DESY)
The planar four-point master integrals for massive two-loop Bhabha scattering
19 pages, 2 figures
Nucl.Phys. B751 (2006) 1-17
10.1016/j.nuclphysb.2006.05.033
DESY 06-021, WUE-ITP-2006-004, SFB/CPP-06-17
hep-ph
null
We present the values of the complete set of planar four-point Master Integrals needed for massive Bhabha scattering in the limit of fixed angle and high energy at the two-loop level. The integrals have been calculated using direct expansions of Mellin-Barnes representations, followed by a resummation of resulting harmonic series.
[ { "created": "Wed, 12 Apr 2006 09:15:13 GMT", "version": "v1" } ]
2010-04-05
[ [ "Czakon", "M.", "", "Univ. Wuerzburg" ], [ "Gluza", "J.", "", "Univ. of Silesia" ], [ "Riemann", "T.", "", "DESY" ] ]
We present the values of the complete set of planar four-point Master Integrals needed for massive Bhabha scattering in the limit of fixed angle and high energy at the two-loop level. The integrals have been calculated using direct expansions of Mellin-Barnes representations, followed by a resummation of resulting harmonic series.
1712.07494
Avik Banerjee
Avik Banerjee, Gautam Bhattacharyya, Nilanjana Kumar, Tirtha Sankar Ray
Constraining Composite Higgs Models using LHC data
23 pages, 6 captioned figures, 6 tables, footnote added, references updated, matches version published in JHEP
JHEP 1803 (2018) 062
10.1007/JHEP03(2018)062
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We systematically study the modifications in the couplings of the Higgs boson, when identified as a pseudo Nambu-Goldstone boson of a strong sector, in the light of LHC Run 1 and Run 2 data. For the minimal coset SO(5)/SO(4) of the strong sector, we focus on scenarios where the standard model left- and right-handed fermions (specifically, the top and bottom quarks) are either in 5 or in the symmetric 14 representation of SO(5). Going beyond the minimal 5L-5R representation, to what we call here the 'extended' models, we observe that it is possible to construct more than one invariant in the Yukawa sector. In such models, the Yukawa couplings of the 125 GeV Higgs boson undergo nontrivial modifications. The pattern of such modifications can be encoded in a generic phenomenological Lagrangian which applies to a wide class of such models. We show that the presence of more than one Yukawa invariant allows the gauge and Yukawa coupling modifiers to be decorrelated in the 'extended' models, and this decorrelation leads to a relaxation of the bound on the compositeness scale (f > 640 GeV at 95% CL, as compared to f > 1 TeV for the minimal 5L-5R representation model). We also study the Yukawa coupling modifications in the context of the next-to-minimal strong sector coset SO(6)/SO(5) for fermion-embedding up to representations of dimension 20. While quantifying our observations, we have performed a detailed chi-square fit using the ATLAS and CMS combined Run 1 and available Run 2 data.
[ { "created": "Wed, 20 Dec 2017 14:26:27 GMT", "version": "v1" }, { "created": "Wed, 10 Jan 2018 13:50:48 GMT", "version": "v2" }, { "created": "Tue, 13 Mar 2018 12:00:33 GMT", "version": "v3" } ]
2018-03-14
[ [ "Banerjee", "Avik", "" ], [ "Bhattacharyya", "Gautam", "" ], [ "Kumar", "Nilanjana", "" ], [ "Ray", "Tirtha Sankar", "" ] ]
We systematically study the modifications in the couplings of the Higgs boson, when identified as a pseudo Nambu-Goldstone boson of a strong sector, in the light of LHC Run 1 and Run 2 data. For the minimal coset SO(5)/SO(4) of the strong sector, we focus on scenarios where the standard model left- and right-handed fermions (specifically, the top and bottom quarks) are either in 5 or in the symmetric 14 representation of SO(5). Going beyond the minimal 5L-5R representation, to what we call here the 'extended' models, we observe that it is possible to construct more than one invariant in the Yukawa sector. In such models, the Yukawa couplings of the 125 GeV Higgs boson undergo nontrivial modifications. The pattern of such modifications can be encoded in a generic phenomenological Lagrangian which applies to a wide class of such models. We show that the presence of more than one Yukawa invariant allows the gauge and Yukawa coupling modifiers to be decorrelated in the 'extended' models, and this decorrelation leads to a relaxation of the bound on the compositeness scale (f > 640 GeV at 95% CL, as compared to f > 1 TeV for the minimal 5L-5R representation model). We also study the Yukawa coupling modifications in the context of the next-to-minimal strong sector coset SO(6)/SO(5) for fermion-embedding up to representations of dimension 20. While quantifying our observations, we have performed a detailed chi-square fit using the ATLAS and CMS combined Run 1 and available Run 2 data.
hep-ph/0202015
Di Qing
Bo-Qiang Ma, Di Qing and Ivan Schmidt
Electromagnetic Form Factors of Nucleons in a Light-cone Diquark Model
16 pages, Revtex4, minor changes, to appear in Phys. Rev. C
Phys.Rev. C65 (2002) 035205
10.1103/PhysRevC.65.035205
USM-TH-115
hep-ph hep-ex nucl-ex nucl-th
null
We investigate the electromagnetic form factors of nucleons within a simple relativistic quark spectator-diquark model using the light-cone formalism. Melosh rotations are applied to both quark and vector diquark. It is shown that the difference between vector and scalar spectator diquarks reproduces the right electric form factor of neutrons, and both the form factors $G_E(Q^2)$ and $G_M(Q^2)$ of the proton and neutron agree with experimental data well up to $Q^2=2 ~\rm{GeV}^2$ in this simple model.
[ { "created": "Mon, 4 Feb 2002 08:35:28 GMT", "version": "v1" }, { "created": "Tue, 12 Feb 2002 06:21:31 GMT", "version": "v2" } ]
2009-11-07
[ [ "Ma", "Bo-Qiang", "" ], [ "Qing", "Di", "" ], [ "Schmidt", "Ivan", "" ] ]
We investigate the electromagnetic form factors of nucleons within a simple relativistic quark spectator-diquark model using the light-cone formalism. Melosh rotations are applied to both quark and vector diquark. It is shown that the difference between vector and scalar spectator diquarks reproduces the right electric form factor of neutrons, and both the form factors $G_E(Q^2)$ and $G_M(Q^2)$ of the proton and neutron agree with experimental data well up to $Q^2=2 ~\rm{GeV}^2$ in this simple model.
1212.5857
Frash\"er Loshaj
Dmitri E. Kharzeev, Frasher Loshaj
Jet energy loss and fragmentation in heavy ion collisions
5 pages, 5 figures. More results and a new figure added. Few other additions to the text. References added
null
10.1103/PhysRevD.87.077501
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent LHC results indicate a suppression of jet fragmentation functions in Pb-Pb collisions at intermediate values of $\xi=\ln(1/z)$. This seems to contradict the picture of energy loss based on the induced QCD radiation that is expected to lead to the enhancement of in-medium fragmentation functions. We use an effective 1+1 dimensional quasi-Abelian model to describe the dynamical modification of jet fragmentation in the medium. We find that this approach describes the data, and argue that there is no contradiction between the LHC results and the picture of QCD radiation induced by the in-medium scattering of the jet. The physics that underlies the suppression of the in-medium fragmentation function at intermediate values of $\xi=\ln(1/z)$ is the partial screening of the color charge of the jet by the comoving medium-induced gluon.
[ { "created": "Mon, 24 Dec 2012 03:11:13 GMT", "version": "v1" }, { "created": "Wed, 10 Apr 2013 18:01:14 GMT", "version": "v2" } ]
2015-06-12
[ [ "Kharzeev", "Dmitri E.", "" ], [ "Loshaj", "Frasher", "" ] ]
Recent LHC results indicate a suppression of jet fragmentation functions in Pb-Pb collisions at intermediate values of $\xi=\ln(1/z)$. This seems to contradict the picture of energy loss based on the induced QCD radiation that is expected to lead to the enhancement of in-medium fragmentation functions. We use an effective 1+1 dimensional quasi-Abelian model to describe the dynamical modification of jet fragmentation in the medium. We find that this approach describes the data, and argue that there is no contradiction between the LHC results and the picture of QCD radiation induced by the in-medium scattering of the jet. The physics that underlies the suppression of the in-medium fragmentation function at intermediate values of $\xi=\ln(1/z)$ is the partial screening of the color charge of the jet by the comoving medium-induced gluon.
hep-ph/9801410
Mike Berger
V. Barger, M. S. Berger, T. Han
Chargino mass determination at a muon collider
13 pages, 3 figures
Phys.Rev.D59:071701,1999
10.1103/PhysRevD.59.071701
MAD-PH-98-1036, IUHET-381
hep-ph
null
We analyze the prospects at a muon collider for measuring chargino masses in the $\mu^+\mu^-\to \tilde{\chi}^+\tilde{\chi}^-$ process in the threshold region. We find that for the lighter chargino of a mass $100-200$ GeV, a measurement better than $50-300$ MeV should be possible with 50 fb$^{-1}$ integrated luminosity. The accuracy obtained here is better than with other techniques or at other facilities. The muon sneutrino mass, which enters through the $\tilde{\nu}_\mu$ exchange diagram, can also be simultaneously measured to a few GeV if it is not too heavy.
[ { "created": "Mon, 26 Jan 1998 04:40:47 GMT", "version": "v1" } ]
2008-11-26
[ [ "Barger", "V.", "" ], [ "Berger", "M. S.", "" ], [ "Han", "T.", "" ] ]
We analyze the prospects at a muon collider for measuring chargino masses in the $\mu^+\mu^-\to \tilde{\chi}^+\tilde{\chi}^-$ process in the threshold region. We find that for the lighter chargino of a mass $100-200$ GeV, a measurement better than $50-300$ MeV should be possible with 50 fb$^{-1}$ integrated luminosity. The accuracy obtained here is better than with other techniques or at other facilities. The muon sneutrino mass, which enters through the $\tilde{\nu}_\mu$ exchange diagram, can also be simultaneously measured to a few GeV if it is not too heavy.
hep-ph/0004195
Fernando T. Brandt
F. T. Brandt, Ashok Das and J. Frenkel
Parity-breaking electromagnetic interactions in thermal QED_3
9 pages, 2 figures
null
null
null
hep-ph hep-th
null
We examine the parity violating terms generated by the box diagram in QED_3 at finite temperature. These lead to both extensive as well as non-extensive effective actions, which have very distinct behavior in the long wavelength and static limits. We discuss a large gauge Ward identity for the leading terms in the static limit, whose solution coincides with the effective action proposed earlier.
[ { "created": "Thu, 20 Apr 2000 14:58:39 GMT", "version": "v1" } ]
2007-05-23
[ [ "Brandt", "F. T.", "" ], [ "Das", "Ashok", "" ], [ "Frenkel", "J.", "" ] ]
We examine the parity violating terms generated by the box diagram in QED_3 at finite temperature. These lead to both extensive as well as non-extensive effective actions, which have very distinct behavior in the long wavelength and static limits. We discuss a large gauge Ward identity for the leading terms in the static limit, whose solution coincides with the effective action proposed earlier.
2003.13276
Phung Van Dong
Phung Van Dong
Flipping principle for neutrino mass and dark matter
5 pages, 3 tables, 1 figure; Matches published version in PRD Rapid Communication
Phys. Rev. D 102, 011701 (2020)
10.1103/PhysRevD.102.011701
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Flipping a symmetry often leads to a more fundamental symmetry and new physics insight. Applying this principle to the standard model electroweak symmetry, we obtain a novel gauge symmetry, which defines dark charge besides electric charge, neutrino mass mechanism, and resultant dark parity as residual flipped symmetry. The dark parity divides the model particles into two classes: odd and even. The dark matter candidate transforms as a fermion or a scalar singlet, having a mass below the electron mass, being stabilized by the dark parity. Scenarios for consistent neutrino mass generation and dark matter relic are proposed. The nature and further implication of the flipping approach are determined.
[ { "created": "Mon, 30 Mar 2020 08:55:23 GMT", "version": "v1" }, { "created": "Fri, 17 Jul 2020 12:45:51 GMT", "version": "v2" } ]
2020-07-22
[ [ "Van Dong", "Phung", "" ] ]
Flipping a symmetry often leads to a more fundamental symmetry and new physics insight. Applying this principle to the standard model electroweak symmetry, we obtain a novel gauge symmetry, which defines dark charge besides electric charge, neutrino mass mechanism, and resultant dark parity as residual flipped symmetry. The dark parity divides the model particles into two classes: odd and even. The dark matter candidate transforms as a fermion or a scalar singlet, having a mass below the electron mass, being stabilized by the dark parity. Scenarios for consistent neutrino mass generation and dark matter relic are proposed. The nature and further implication of the flipping approach are determined.
hep-ph/0606234
David Morrissey
David E. Morrissey, James D. Wells
Holomorphic selection rules, the origin of the mu term, and thermal inflation
18 pages, 1 figure
JHEP 0701:102,2007
10.1088/1126-6708/2007/01/102
MCTP-06-14
hep-ph
null
When an abelian gauge theory with integer charges is spontaneously broken by the expectation value of a charge Q field, there remains a Z_Q discrete symmetry. In a supersymmetric theory, holomorphy adds additional constraints on the operators that can appear in the effective superpotential. As a result, operators with the same mass dimension but opposite sign charges can have very different coupling strengths. In the present work we characterize the operator hierarchies in the effective theory due to holomorphy, and show that there exist simple relationships between the size of an operator and its mass dimension and charge. Using such holomorphy-induced operator hierarchies, we construct a simple model with a naturally small supersymmetric mu term. This model also provides a concrete realization of late-time thermal inflation, which has the ability to solve the gravitino and moduli problems of weak-scale supersymmetry.
[ { "created": "Wed, 21 Jun 2006 17:48:43 GMT", "version": "v1" } ]
2010-10-27
[ [ "Morrissey", "David E.", "" ], [ "Wells", "James D.", "" ] ]
When an abelian gauge theory with integer charges is spontaneously broken by the expectation value of a charge Q field, there remains a Z_Q discrete symmetry. In a supersymmetric theory, holomorphy adds additional constraints on the operators that can appear in the effective superpotential. As a result, operators with the same mass dimension but opposite sign charges can have very different coupling strengths. In the present work we characterize the operator hierarchies in the effective theory due to holomorphy, and show that there exist simple relationships between the size of an operator and its mass dimension and charge. Using such holomorphy-induced operator hierarchies, we construct a simple model with a naturally small supersymmetric mu term. This model also provides a concrete realization of late-time thermal inflation, which has the ability to solve the gravitino and moduli problems of weak-scale supersymmetry.
hep-ph/0012183
Matthias Neubert
Thomas Becher, Matthias Neubert, Alexey A. Petrov (Cornell U.)
Two-Loop Renormalization of Heavy--Light Currents at Order 1/m_Q in the Heavy-Quark Expansion
16 pages, 2 figures; third author added and one reference updated, results unchanged
Nucl.Phys. B611 (2001) 367-382
10.1016/S0550-3213(01)00341-8
CLNS 00/1713
hep-ph
null
We present exact results, at next-to-leading order in renormalization-group improved perturbation theory, for the Wilson coefficients appearing at order 1/m_Q in the heavy-quark expansion of heavy-light current operators. To this end, we complete the calculation of the corresponding two-loop anomalous dimension matrix. Our results are important for determinations of |V_{ub}| using exclusive and inclusive semileptonic B decays. They are also relevant to computations of the decay constant f_B based on a heavy-quark expansion.
[ { "created": "Thu, 14 Dec 2000 23:46:44 GMT", "version": "v1" }, { "created": "Tue, 22 May 2001 13:47:28 GMT", "version": "v2" } ]
2009-10-31
[ [ "Becher", "Thomas", "", "Cornell U." ], [ "Neubert", "Matthias", "", "Cornell U." ], [ "Petrov", "Alexey A.", "", "Cornell U." ] ]
We present exact results, at next-to-leading order in renormalization-group improved perturbation theory, for the Wilson coefficients appearing at order 1/m_Q in the heavy-quark expansion of heavy-light current operators. To this end, we complete the calculation of the corresponding two-loop anomalous dimension matrix. Our results are important for determinations of |V_{ub}| using exclusive and inclusive semileptonic B decays. They are also relevant to computations of the decay constant f_B based on a heavy-quark expansion.
1207.7152
Nobuhito Maru
Hiroshi Itoyama and Nobuhito Maru
D-term Dynamical SUSY Breaking
10 pages, 1 figure, prepared for the proceedings of the conference "Progress in Quantum Field Theory and String Theory", April 3-7 2012, Media Center, Osaka City University, Japan, a reference added
null
10.1142/S2010194513009392
OCU-PHYS 373
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider an N=1 supersymmetric U(N) gauge theory with an adjoint chiral multiplet. By developing a self-consistent Hartree-Fock approximation to the leading order which is reminiscent of that of the BCS/NJL in the superconductivity/chiral symmetry, we show that the N=1 supersymmetry is spontaneously broken, giving a mixed Majorana-Dirac mass term for gaugino due to the nonvanishing D-term VEV and F-term one induced by D-term.
[ { "created": "Tue, 31 Jul 2012 02:46:17 GMT", "version": "v1" }, { "created": "Tue, 21 Aug 2012 06:17:22 GMT", "version": "v2" } ]
2015-06-05
[ [ "Itoyama", "Hiroshi", "" ], [ "Maru", "Nobuhito", "" ] ]
We consider an N=1 supersymmetric U(N) gauge theory with an adjoint chiral multiplet. By developing a self-consistent Hartree-Fock approximation to the leading order which is reminiscent of that of the BCS/NJL in the superconductivity/chiral symmetry, we show that the N=1 supersymmetry is spontaneously broken, giving a mixed Majorana-Dirac mass term for gaugino due to the nonvanishing D-term VEV and F-term one induced by D-term.
1110.0449
Haitang Yang
Peng Wang, Houwen Wu and Haitang Yang
Superluminal Neutrinos and Monopoles
V2, 4 pages. Typo corrected, References added. Content improved significantly. Added discussions about cosmic strings
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this letter, we show that superluminal neutrinos announced by OPERA could be explained by the existence of a monopole, which is left behind after the spontaneous symmetry breaking (SSB) phase transition of some scalar fields in the universe. We assume the 't Hooft-Polyakov monopole couples to the neutrinos but not photon fields. The monopole introduces a different effective metric to the neutrinos from the one experienced by photons. We find that the superluminal propagation only exists in a very short distance from the monopole, about $10^3$ cm in OPERA. No matter how far they travel, neutrinos always arrive earlier than photons by the same amount of time, provided a monopole existing on or close to their trajectories. This conclusion can be tested by future experiments. The result reconciles the contradiction between OPERA and supernova neutrinos. We further exclude cosmic strings as a possible theoretical explanation.
[ { "created": "Mon, 3 Oct 2011 19:26:05 GMT", "version": "v1" }, { "created": "Fri, 7 Oct 2011 17:25:01 GMT", "version": "v2" } ]
2011-10-10
[ [ "Wang", "Peng", "" ], [ "Wu", "Houwen", "" ], [ "Yang", "Haitang", "" ] ]
In this letter, we show that superluminal neutrinos announced by OPERA could be explained by the existence of a monopole, which is left behind after the spontaneous symmetry breaking (SSB) phase transition of some scalar fields in the universe. We assume the 't Hooft-Polyakov monopole couples to the neutrinos but not photon fields. The monopole introduces a different effective metric to the neutrinos from the one experienced by photons. We find that the superluminal propagation only exists in a very short distance from the monopole, about $10^3$ cm in OPERA. No matter how far they travel, neutrinos always arrive earlier than photons by the same amount of time, provided a monopole existing on or close to their trajectories. This conclusion can be tested by future experiments. The result reconciles the contradiction between OPERA and supernova neutrinos. We further exclude cosmic strings as a possible theoretical explanation.
1308.3625
Chun-Yu Cui
Chun-Yu Cui, Yong-Lu Liu and Ming-Qiu Huang
Could $Z_{c}(4025)$ be a $J^{P}=1^{+}$ $D^{*}\bar{D^{*}}$ molecular state?
7 pages, 4 figures.Published in Eur.Phys.J. C73 (2013) 2661. arXiv admin note: text overlap with arXiv:1304.1850
null
10.1140/epjc/s10052-013-2661-x
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate whether the newly observed narrow resonance $Z_{c}(4025)$ can be described as a $D^{*}\bar{D^{*}}$ molecular state with quantum numbers $J^{P}=1^{+}$. Using QCD sum rules, we consider contributions up to dimension six in the operator product expansion and work at leading order of $\alpha_{s}$. The mass obtained for this state is $(4.05\pm 0.28) \mbox{GeV}$. It is concluded that $D^{*}\bar{D^{*}}$ molecular state is a possible candidate for $Z_{c}(4025)$.
[ { "created": "Fri, 16 Aug 2013 13:14:17 GMT", "version": "v1" }, { "created": "Tue, 18 Mar 2014 13:17:15 GMT", "version": "v2" } ]
2014-03-19
[ [ "Cui", "Chun-Yu", "" ], [ "Liu", "Yong-Lu", "" ], [ "Huang", "Ming-Qiu", "" ] ]
We investigate whether the newly observed narrow resonance $Z_{c}(4025)$ can be described as a $D^{*}\bar{D^{*}}$ molecular state with quantum numbers $J^{P}=1^{+}$. Using QCD sum rules, we consider contributions up to dimension six in the operator product expansion and work at leading order of $\alpha_{s}$. The mass obtained for this state is $(4.05\pm 0.28) \mbox{GeV}$. It is concluded that $D^{*}\bar{D^{*}}$ molecular state is a possible candidate for $Z_{c}(4025)$.
1109.3093
Brian C. Tiburzi
Aleksey Cherman, Brian C. Tiburzi
The Fermion Sign Problem at Finite Density, and Large Nc Orbifold Equivalence
8 pages, 2 figures, talk given by BCT at DPF 2011, Providence, Rhode Island, USA, 9-13 Aug 2011
null
null
MIT-CTP 4296, RBRC 925
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of QCD at finite baryon density is severely hampered by the so-called fermion sign problem. As a result, we have no known first principles approach to study nuclear matter, or neutron stars from QCD. On the surface, the large Nc limit does not seem to simplify matters. In this limit, however, one can exploit dualities that exist between strongly coupled gauge theories. Our focus will be on some rather novel orbifold equivalences that have recently been discovered at finite density. These equivalences relate strongly coupled theories plagued by a sign problem, to strongly coupled theories free of sign problems. As a result, such dualities give deeper insight into the nature of the sign problem and possibly provide a way to simulate QCD at finite density in the large Nc limit.
[ { "created": "Wed, 14 Sep 2011 14:34:39 GMT", "version": "v1" } ]
2011-10-27
[ [ "Cherman", "Aleksey", "" ], [ "Tiburzi", "Brian C.", "" ] ]
The study of QCD at finite baryon density is severely hampered by the so-called fermion sign problem. As a result, we have no known first principles approach to study nuclear matter, or neutron stars from QCD. On the surface, the large Nc limit does not seem to simplify matters. In this limit, however, one can exploit dualities that exist between strongly coupled gauge theories. Our focus will be on some rather novel orbifold equivalences that have recently been discovered at finite density. These equivalences relate strongly coupled theories plagued by a sign problem, to strongly coupled theories free of sign problems. As a result, such dualities give deeper insight into the nature of the sign problem and possibly provide a way to simulate QCD at finite density in the large Nc limit.
hep-ph/0608256
Gorazd Cvetic
Gorazd Cvetic and Cristian Valenzuela
Various versions of analytic QCD and skeleton-motivated evaluation of observables
30 pages, 14 eps-figures; v3: parameters of the analytic QCD models M1 and M2 were refined, the numerical results modified accordingly, new paragraph at the end of Sec.II and at the end of Sec.III, discussion of Figs.4 extended, references added; version to appear in PRD
Phys.Rev.D74:114030,2006; Erratum-ibid.D84:019902,2011
10.1103/PhysRevD.74.114030 10.1103/PhysRevD.84.019902
USM-TH-195
hep-ph
null
We present skeleton-motivated evaluation of QCD observables. The approach can be applied in analytic versions of QCD in certain classes of renormalization schemes. We present two versions of analytic QCD which can be regarded as low-energy modifications of the ``minimal'' analytic QCD and which reproduce the measured value of the semihadronic tau decay ratio r{tau}. Further, we describe an approach of calculating the higher order analytic couplings Ak (k=2,3,...) on the basis of logarithmic derivatives of the analytic coupling A1(Q^2). This approach can be easily applied in any version of analytic QCD. We adjust the free parameters of the afore-mentioned two analytic models in such a way that the skeleton-motivated evaluation reproduces the correct known values of r{tau} and of the Bjorken polarized sum rule (BjPSR) db(Q^2) at a given point (e.g., at Q^2=2 GeV^2). We then evaluate the low-energy behavior of the Adler function dv(Q^2) and the BjPSR db(Q^2) in the afore-mentioned evaluation approach, in the three analytic versions of QCD. We compare with the results obtained in the ``minimal'' analytic QCD and with the evaluation approach of Milton et al. and Shirkov.
[ { "created": "Wed, 23 Aug 2006 19:58:32 GMT", "version": "v1" }, { "created": "Tue, 29 Aug 2006 19:25:15 GMT", "version": "v2" }, { "created": "Fri, 24 Nov 2006 20:11:41 GMT", "version": "v3" } ]
2011-08-12
[ [ "Cvetic", "Gorazd", "" ], [ "Valenzuela", "Cristian", "" ] ]
We present skeleton-motivated evaluation of QCD observables. The approach can be applied in analytic versions of QCD in certain classes of renormalization schemes. We present two versions of analytic QCD which can be regarded as low-energy modifications of the ``minimal'' analytic QCD and which reproduce the measured value of the semihadronic tau decay ratio r{tau}. Further, we describe an approach of calculating the higher order analytic couplings Ak (k=2,3,...) on the basis of logarithmic derivatives of the analytic coupling A1(Q^2). This approach can be easily applied in any version of analytic QCD. We adjust the free parameters of the afore-mentioned two analytic models in such a way that the skeleton-motivated evaluation reproduces the correct known values of r{tau} and of the Bjorken polarized sum rule (BjPSR) db(Q^2) at a given point (e.g., at Q^2=2 GeV^2). We then evaluate the low-energy behavior of the Adler function dv(Q^2) and the BjPSR db(Q^2) in the afore-mentioned evaluation approach, in the three analytic versions of QCD. We compare with the results obtained in the ``minimal'' analytic QCD and with the evaluation approach of Milton et al. and Shirkov.
1107.2913
David Blaschke
D. Blaschke, P. Costa, Yu.L. Kalinovsky
D mesons at finite temperature and density in the PNJL model
7 pages, 7 figures, references, text and figure 1 added
Phys.Rev. D85 (2012) 034005
10.1103/PhysRevD.85.034005
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study D meson resonances in hot, dense quark matter within the NJL model and its Polyakov-loop extension. We show that the mass splitting between D^+ and D^- mesons is moderate, not in excess of 100 MeV. When the decay channel into quasifree quarks opens (Mott effect) at densities above twice saturation density, the decay width reaches rapidly the value of 200 MeV which entails a spectral broadening sufficient to open J/psi dissociation processes. Contrary to results from hadronic mean-field theories, the chiral quark model does not support the scenario of a dropping D meson masses so that scenarios for J/psi dissociation by quark rearrangement built on the lowering of the threshold for this process in a hot and dense medium have to be reconsidered and should account for the spectral broadening.
[ { "created": "Thu, 14 Jul 2011 19:57:28 GMT", "version": "v1" }, { "created": "Thu, 21 Jul 2011 17:01:32 GMT", "version": "v2" }, { "created": "Sat, 19 Nov 2011 12:04:17 GMT", "version": "v3" } ]
2015-03-19
[ [ "Blaschke", "D.", "" ], [ "Costa", "P.", "" ], [ "Kalinovsky", "Yu. L.", "" ] ]
We study D meson resonances in hot, dense quark matter within the NJL model and its Polyakov-loop extension. We show that the mass splitting between D^+ and D^- mesons is moderate, not in excess of 100 MeV. When the decay channel into quasifree quarks opens (Mott effect) at densities above twice saturation density, the decay width reaches rapidly the value of 200 MeV which entails a spectral broadening sufficient to open J/psi dissociation processes. Contrary to results from hadronic mean-field theories, the chiral quark model does not support the scenario of a dropping D meson masses so that scenarios for J/psi dissociation by quark rearrangement built on the lowering of the threshold for this process in a hot and dense medium have to be reconsidered and should account for the spectral broadening.
1809.04990
Amalia Betancur
Amalia Betancur, \'Oscar Zapata
Phenomenology of doublet-triplet fermionic dark matter in nonstandard cosmology and multicomponent dark sectors
28 pages, version to match PRD
Phys. Rev. D 98, 095003 (2018)
10.1103/PhysRevD.98.095003
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We consider the doublet-triplet fermionic model in the scheme of the custodial limit when the dark matter (DM) candidate is pure doublet and lies at the electroweak scale. This scheme, despite being an appealing and promising DM model, is severely constrained by the interplay between the DM relic density constraint and the LHC measurement of the Higgs diphoton decay rate. In this work, the DM relic density is considered to arise from either a nonstandard cosmology scenario or as a part of a larger sector encompassing other DM particles, this in order to saturate the observed relic abundance. For these scenarios we investigate the impact of the new sector in different collider observables, and study constraints coming from direct detection and indirect detection of gamma-rays both in the diffuse and linelike spectrum. As a result, we find that in the nonstandard cosmology scenario most experiments impose, up to a certain point, restrictions, though large portions of the parameter space are still viable. For the multicomponent case, only direct detection imposes constraints.
[ { "created": "Thu, 13 Sep 2018 14:33:54 GMT", "version": "v1" }, { "created": "Thu, 8 Nov 2018 19:19:12 GMT", "version": "v2" } ]
2018-11-12
[ [ "Betancur", "Amalia", "" ], [ "Zapata", "Óscar", "" ] ]
We consider the doublet-triplet fermionic model in the scheme of the custodial limit when the dark matter (DM) candidate is pure doublet and lies at the electroweak scale. This scheme, despite being an appealing and promising DM model, is severely constrained by the interplay between the DM relic density constraint and the LHC measurement of the Higgs diphoton decay rate. In this work, the DM relic density is considered to arise from either a nonstandard cosmology scenario or as a part of a larger sector encompassing other DM particles, this in order to saturate the observed relic abundance. For these scenarios we investigate the impact of the new sector in different collider observables, and study constraints coming from direct detection and indirect detection of gamma-rays both in the diffuse and linelike spectrum. As a result, we find that in the nonstandard cosmology scenario most experiments impose, up to a certain point, restrictions, though large portions of the parameter space are still viable. For the multicomponent case, only direct detection imposes constraints.
1703.01757
Chitta Ranjan Das
L.V. Laperashvili, H.B. Nielsen, C.D. Froggatt, B.G. Sidharth and C.R. Das
New Resonances at LHC are possible. Multiple Point Principle and New Bound States in the Standard Model
18 pages, 6 figures, Presented by Larisa Laperashvili at the "Winter School on Astronomy", organized by B M Birla Science Center, India, and Dept.of Physics & Astronomy, Western University, Canada, February 20-23, 2017, Hyderabad, India
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the present paper we argue that the correction to the Higgs mass coming from the bound state of 6 top and 6 anti-top quarks, predicted early by C.D. Froggatt, H.B. Nielsen and L.V. Laperashvili, leads to the Standard Model (SM) vacuum stability and confirms the accuracy of the multiple point principle (principle of degenerate vacua) for all experimentally valued SM parameters (Higgs mass, top-quark mass, etc.). The aim to get the vacua degeneracy requires a mass of the bound state in the region of 770 GeV.
[ { "created": "Mon, 6 Mar 2017 08:26:00 GMT", "version": "v1" } ]
2017-03-07
[ [ "Laperashvili", "L. V.", "" ], [ "Nielsen", "H. B.", "" ], [ "Froggatt", "C. D.", "" ], [ "Sidharth", "B. G.", "" ], [ "Das", "C. R.", "" ] ]
In the present paper we argue that the correction to the Higgs mass coming from the bound state of 6 top and 6 anti-top quarks, predicted early by C.D. Froggatt, H.B. Nielsen and L.V. Laperashvili, leads to the Standard Model (SM) vacuum stability and confirms the accuracy of the multiple point principle (principle of degenerate vacua) for all experimentally valued SM parameters (Higgs mass, top-quark mass, etc.). The aim to get the vacua degeneracy requires a mass of the bound state in the region of 770 GeV.
1301.4470
Edward Shuryak
Edward Shuryak and Ismail Zahed
High Multiplicity pp and pA Collisions: Hydrodynamics at its Edge
Unlike previous, this versions included only macroscopic (hydrodynamical) part, and microscopic one, while the Pomeron discussion will appear separately. One important new element are CMS and ALICE data on high multiplicity pA with identified secondaries: as we discuss now, those confirm our prediction of enhanced radial flow
Phys. Rev. C 88, 044915 (2013)
10.1103/PhysRevC.88.044915
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With growing multiplicity, the pp and pA collisions enter the domain where the macroscopic description (thermodynamics and hydrodynamics) becomes applicable. We discuss this situation, first with simplified thought experiments, then with some idealized representative cases, and finally address the real data. For clarity, we don't do it numerically but analytically, using the Gubser solution. We found that the radial flow is expected to increase from central AA to central pA, while the elliptic flow decreases, with higher harmonics being comparable. In the second part of the paper we approach the problem from the opposite side, using a string-based Pomeron model. We extensively study the magnitude and distribution of the viscous corrections, in Navier-Stokes and Israel-Stuart approximations, ending with higher gradient re-summation proposed by Lublinsky and Shuryak. We found those corrections growing, from AA to pA to pp, but remaining at the manageable size even in the last case.
[ { "created": "Fri, 18 Jan 2013 19:30:38 GMT", "version": "v1" }, { "created": "Fri, 1 Feb 2013 19:56:39 GMT", "version": "v2" }, { "created": "Mon, 25 Feb 2013 17:24:25 GMT", "version": "v3" }, { "created": "Tue, 6 Aug 2013 14:38:17 GMT", "version": "v4" } ]
2013-10-30
[ [ "Shuryak", "Edward", "" ], [ "Zahed", "Ismail", "" ] ]
With growing multiplicity, the pp and pA collisions enter the domain where the macroscopic description (thermodynamics and hydrodynamics) becomes applicable. We discuss this situation, first with simplified thought experiments, then with some idealized representative cases, and finally address the real data. For clarity, we don't do it numerically but analytically, using the Gubser solution. We found that the radial flow is expected to increase from central AA to central pA, while the elliptic flow decreases, with higher harmonics being comparable. In the second part of the paper we approach the problem from the opposite side, using a string-based Pomeron model. We extensively study the magnitude and distribution of the viscous corrections, in Navier-Stokes and Israel-Stuart approximations, ending with higher gradient re-summation proposed by Lublinsky and Shuryak. We found those corrections growing, from AA to pA to pp, but remaining at the manageable size even in the last case.
hep-ph/9506475
Guy David Moore
Guy D. Moore and Tomislav Prokopec
How fast can the wall move? A study of the electroweak phase transition dynamics
42 pages, plain latex, with three figures. Minor editing August 1 (we figured out how to do analytically some integrals we previously did numerically, made corresponding (slight) changes to numerical results, and corrected some typos.)
Phys.Rev.D52:7182-7204,1995
10.1103/PhysRevD.52.7182
PUP-TH-1544 and LANCS-TH/9517
hep-ph
null
We consider the dynamics of bubble growth in the Minimal Standard Model at the electroweak phase transition and determine the shape and the velocity of the phase boundary, or bubble wall. We show that in the semi-classical approximation the friction on the wall arises from the deviation of massive particle populations from thermal equilibrium. We treat these with Boltzmann equations in a fluid approximation. This approximation is reasonable for the top quarks and the light species while it underestimates the friction from the infrared $W$ bosons and Higgs particles. We use the two-loop finite temperature effective potential and find a subsonic bubble wall for the whole range of Higgs masses $0<m_H<90$GeV. The result is weakly dependent on $m_H$: the wall velocity $v_w$ falls in the range $0.36<v_w<0.44$, while the wall thickness is in the range $29> L T > 23 $. The wall is thicker than the phase equilibrium value because out of equilibrium particles exert more friction on the back than on the base of a moving wall. We also consider the effect of an infrared gauge condensate which may exist in the symmetric phase; modelling it simplemindedly, we find that the wall may become supersonic, but not ultrarelativistic.
[ { "created": "Fri, 30 Jun 1995 21:47:58 GMT", "version": "v1" }, { "created": "Wed, 2 Aug 1995 01:46:55 GMT", "version": "v2" } ]
2014-11-17
[ [ "Moore", "Guy D.", "" ], [ "Prokopec", "Tomislav", "" ] ]
We consider the dynamics of bubble growth in the Minimal Standard Model at the electroweak phase transition and determine the shape and the velocity of the phase boundary, or bubble wall. We show that in the semi-classical approximation the friction on the wall arises from the deviation of massive particle populations from thermal equilibrium. We treat these with Boltzmann equations in a fluid approximation. This approximation is reasonable for the top quarks and the light species while it underestimates the friction from the infrared $W$ bosons and Higgs particles. We use the two-loop finite temperature effective potential and find a subsonic bubble wall for the whole range of Higgs masses $0<m_H<90$GeV. The result is weakly dependent on $m_H$: the wall velocity $v_w$ falls in the range $0.36<v_w<0.44$, while the wall thickness is in the range $29> L T > 23 $. The wall is thicker than the phase equilibrium value because out of equilibrium particles exert more friction on the back than on the base of a moving wall. We also consider the effect of an infrared gauge condensate which may exist in the symmetric phase; modelling it simplemindedly, we find that the wall may become supersonic, but not ultrarelativistic.
1907.00237
Matthias Lutz F.M.
Matthias F.M. Lutz, Yonggoo Heo and Xiao-Yu Guo
A generalized Higgs potential with two degenerate minima for a dark QCD matter scenario
8 pages, five figures, published version
null
10.1140/epjc/s10052-020-7884-z
null
hep-ph astro-ph.GA
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the Higgs potential in generalizations of the Standard Model. The possibility of the potential to develop two almost degenerate minima is explored. This would imply that QCD matter at two distinct sets of quark masses is relevant for astrophysics and cosmology. If in the exotic minimum the QCD matter ground state is electromagnetically neutral, dark matter may consist of QCD matter and antimatter in bubbles of the Higgs field. We predict an abundance of gamma rays in the few MeV region as messengers of dark matter regions in space. In addition the ratio of dark matter to normal matter is expected to show a time dependence.
[ { "created": "Sat, 29 Jun 2019 16:44:26 GMT", "version": "v1" }, { "created": "Wed, 2 Oct 2019 06:05:21 GMT", "version": "v2" }, { "created": "Fri, 8 Nov 2019 14:47:07 GMT", "version": "v3" }, { "created": "Fri, 27 Mar 2020 15:03:17 GMT", "version": "v4" } ]
2020-05-20
[ [ "Lutz", "Matthias F. M.", "" ], [ "Heo", "Yonggoo", "" ], [ "Guo", "Xiao-Yu", "" ] ]
We consider the Higgs potential in generalizations of the Standard Model. The possibility of the potential to develop two almost degenerate minima is explored. This would imply that QCD matter at two distinct sets of quark masses is relevant for astrophysics and cosmology. If in the exotic minimum the QCD matter ground state is electromagnetically neutral, dark matter may consist of QCD matter and antimatter in bubbles of the Higgs field. We predict an abundance of gamma rays in the few MeV region as messengers of dark matter regions in space. In addition the ratio of dark matter to normal matter is expected to show a time dependence.
0907.2206
Chi-Sing Lam
C.S. Lam
A bottom-up analysis of horizontal symmetry
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The group-theoretical method used to derive horizontal symmetry from neutrino mixing is reviewed and expanded. Some misunderstanding in the literature regarding the result is clarified. The method used previously to find vacuum alignments of $S_4$ is applied to compute those of $A_4$ and $S_3$. A study of effective theories based on these three groups shows that in each case there are just enough free parameters to fit all the masses and the remaining mixing parameters. This places constraint on dynamical models because effective theories are just dynamical models with the right-handed fermions integrated out. How quarks may fit into this scheme is briefly discussed.
[ { "created": "Mon, 13 Jul 2009 16:24:02 GMT", "version": "v1" } ]
2009-07-14
[ [ "Lam", "C. S.", "" ] ]
The group-theoretical method used to derive horizontal symmetry from neutrino mixing is reviewed and expanded. Some misunderstanding in the literature regarding the result is clarified. The method used previously to find vacuum alignments of $S_4$ is applied to compute those of $A_4$ and $S_3$. A study of effective theories based on these three groups shows that in each case there are just enough free parameters to fit all the masses and the remaining mixing parameters. This places constraint on dynamical models because effective theories are just dynamical models with the right-handed fermions integrated out. How quarks may fit into this scheme is briefly discussed.
1607.05566
Xiang Liu
Rui Chen and Xiang Liu
Is the newly reported $X(5568)$ a $B\bar{K}$ molecular state?
6 pages, 3 tables and 1 figure. Version accepted for publication in Phys. Rev. D
Phys. Rev. D 94, 034006 (2016)
10.1103/PhysRevD.94.034006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we perform a dynamical study of the $B^{(*)}$ and $\bar K$ interaction and show that the newly reported $X(5568)$ or $X(5616)$ cannot be assigned to be an isovector $B\bar{K}$ or $B^*\bar{K}$ molecular state. We continue to investigate the isoscalar $B^{(*)}\bar{K}$ systems, and the $B^{(*)}\bar{K}$ systems with isospin $I=0,1$, and predict the existence of several isoscalar $B^{(*)}\bar K^{(*)}$ molecular states. A new task of exploring open-bottom molecular states will be created for future experiments.
[ { "created": "Tue, 19 Jul 2016 13:27:52 GMT", "version": "v1" }, { "created": "Tue, 26 Jul 2016 00:15:44 GMT", "version": "v2" }, { "created": "Thu, 28 Jul 2016 15:20:56 GMT", "version": "v3" } ]
2016-08-08
[ [ "Chen", "Rui", "" ], [ "Liu", "Xiang", "" ] ]
In this work, we perform a dynamical study of the $B^{(*)}$ and $\bar K$ interaction and show that the newly reported $X(5568)$ or $X(5616)$ cannot be assigned to be an isovector $B\bar{K}$ or $B^*\bar{K}$ molecular state. We continue to investigate the isoscalar $B^{(*)}\bar{K}$ systems, and the $B^{(*)}\bar{K}$ systems with isospin $I=0,1$, and predict the existence of several isoscalar $B^{(*)}\bar K^{(*)}$ molecular states. A new task of exploring open-bottom molecular states will be created for future experiments.
0806.1116
Harri Niemi
H. Niemi, K. J. Eskola and P. V. Ruuskanen
Elliptic flow in nuclear collisions at the Large Hadron Collider
11 pages, 10 figures
Phys.Rev.C79:024903,2009
10.1103/PhysRevC.79.024903
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use perfect-fluid hydrodynamical model to predict the elliptic flow coefficients in Pb + Pb collisions at the Large Hadron Collider (LHC). The initial state for the hydrodynamical calculation for central $A + A$ collisions is obtained from the perturbative QCD + saturation (EKRT) model. The centrality dependence of the initial state is modeled by the optical Glauber model. We show that the baseline results obtained from the framework are in good agreement with the data from the Relativistic Heavy Ion Collider (RHIC), and show predictions for the $p_T$ spectra and elliptic flow of pions in Pb + Pb collisions at the LHC. Also mass and multiplicity effects are discussed.
[ { "created": "Fri, 6 Jun 2008 10:03:20 GMT", "version": "v1" } ]
2009-03-04
[ [ "Niemi", "H.", "" ], [ "Eskola", "K. J.", "" ], [ "Ruuskanen", "P. V.", "" ] ]
We use perfect-fluid hydrodynamical model to predict the elliptic flow coefficients in Pb + Pb collisions at the Large Hadron Collider (LHC). The initial state for the hydrodynamical calculation for central $A + A$ collisions is obtained from the perturbative QCD + saturation (EKRT) model. The centrality dependence of the initial state is modeled by the optical Glauber model. We show that the baseline results obtained from the framework are in good agreement with the data from the Relativistic Heavy Ion Collider (RHIC), and show predictions for the $p_T$ spectra and elliptic flow of pions in Pb + Pb collisions at the LHC. Also mass and multiplicity effects are discussed.
hep-ph/0304255
Goran Duplancic
G. Duplancic, B. Nizic
NLO calculations of the exclusive processes in pQCD
4 pages; talk given at the 38th Rencontres de Moriond, QCD and Hadronic Interactions, Les Arcs, France, 22-29 March 2003
null
null
null
hep-ph
null
We present a generally applicable reduction formalism which makes it possible to express an arbitrary tensor and scalar one-loop Feynman integral, with N external lines and massless propagators, in terms of a basic set of eight fundamental scalar Feynman integrals with 2, 3, and 4 external lines, for arbitrary external kinematics. The formalism is particularly suitable for the NLO calculations of exclusive processes at large momentum transfer in pQCD, where all previously developed reduction methods fail due to the presence of collinear external on-shell lines.
[ { "created": "Sun, 27 Apr 2003 17:38:32 GMT", "version": "v1" } ]
2007-05-23
[ [ "Duplancic", "G.", "" ], [ "Nizic", "B.", "" ] ]
We present a generally applicable reduction formalism which makes it possible to express an arbitrary tensor and scalar one-loop Feynman integral, with N external lines and massless propagators, in terms of a basic set of eight fundamental scalar Feynman integrals with 2, 3, and 4 external lines, for arbitrary external kinematics. The formalism is particularly suitable for the NLO calculations of exclusive processes at large momentum transfer in pQCD, where all previously developed reduction methods fail due to the presence of collinear external on-shell lines.
hep-ph/0206093
Cong-Feng Qiao
Cong-Feng Qiao (Hiroshima University)
J/psi Pair Production at the Tevatron
null
Phys.Rev.D66:057504,2002
10.1103/PhysRevD.66.057504
null
hep-ph
null
The double J/psi production in p\bar{p} collision is revisited. It is found that the J/\psi pair production rate at leading order with p_T > 4 GeV in conventional scheme is larger than the rate derived from color-octet mechanism by a factor of five. As the double J/psi production is shown to be attainable with data yet collected at the Tevatron detectors, experimental study on it would be helpful to clarify the validity of the conventional color-singlet description for heavy quarkonium production.
[ { "created": "Mon, 10 Jun 2002 15:18:14 GMT", "version": "v1" }, { "created": "Tue, 11 Jun 2002 02:44:30 GMT", "version": "v2" }, { "created": "Mon, 17 Jun 2002 03:53:08 GMT", "version": "v3" } ]
2011-03-23
[ [ "Qiao", "Cong-Feng", "", "Hiroshima University" ] ]
The double J/psi production in p\bar{p} collision is revisited. It is found that the J/\psi pair production rate at leading order with p_T > 4 GeV in conventional scheme is larger than the rate derived from color-octet mechanism by a factor of five. As the double J/psi production is shown to be attainable with data yet collected at the Tevatron detectors, experimental study on it would be helpful to clarify the validity of the conventional color-singlet description for heavy quarkonium production.
1201.3931
Don Colladay
Don Colladay and Patrick McDonald
Classical Lagrangians for Momentum Dependent Lorentz Violation
14 pages
null
10.1103/PhysRevD.85.044042
null
hep-ph math.DG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Certain momentum-dependent terms in the fermion sector of the Lorentz-violating Standard Model Extension (SME) yield solvable classical lagrangians of a type not mentioned in the literature. These cases yield new relatively simple examples of Finsler and pseudo-Finsler structures. One of the cases involves antisymmetric $d$-type terms and yields a new example of a relatively simple covariant lagrangian.
[ { "created": "Wed, 18 Jan 2012 21:24:24 GMT", "version": "v1" } ]
2013-05-30
[ [ "Colladay", "Don", "" ], [ "McDonald", "Patrick", "" ] ]
Certain momentum-dependent terms in the fermion sector of the Lorentz-violating Standard Model Extension (SME) yield solvable classical lagrangians of a type not mentioned in the literature. These cases yield new relatively simple examples of Finsler and pseudo-Finsler structures. One of the cases involves antisymmetric $d$-type terms and yields a new example of a relatively simple covariant lagrangian.
1702.01458
Konstantin Chetyrkin G.
P. A. Baikov, K. G. Chetyrkin and J. H. K\"uhn
Five-loop fermion anomalous dimension for a general gauge group from four-loop massless propagators
An important reference [47] is corrected
null
10.1007/JHEP04(2017)119
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend the ${\cal O}(\alpha_s^5)$ result of the analytic calculation of the quark mass anomalous dimension in pQCD [1] to the case of a generic gauge group. We present explicit formulas which express the relevant renormalization constants in terms of four-loop massless propagators. We also use our result to shed new light on the old puzzle of the absence of even zetas in results of perturbative calculations for a class of physical observables.
[ { "created": "Sun, 5 Feb 2017 22:12:39 GMT", "version": "v1" }, { "created": "Wed, 8 Feb 2017 13:39:08 GMT", "version": "v2" } ]
2017-05-24
[ [ "Baikov", "P. A.", "" ], [ "Chetyrkin", "K. G.", "" ], [ "Kühn", "J. H.", "" ] ]
We extend the ${\cal O}(\alpha_s^5)$ result of the analytic calculation of the quark mass anomalous dimension in pQCD [1] to the case of a generic gauge group. We present explicit formulas which express the relevant renormalization constants in terms of four-loop massless propagators. We also use our result to shed new light on the old puzzle of the absence of even zetas in results of perturbative calculations for a class of physical observables.
hep-ph/0702019
Raju Venugopalan
Raju Venugopalan
Multiparticle production in the Glasma at NLO and plasma instabilities
4 pages, talk at Quark Matter 2006
J.Phys.G34:S615-618,2007
10.1088/0954-3899/34/8/S56
null
hep-ph
null
We discuss the relation between multi-particle production in the Glasma at next-to-leading order and the physics of plasma instabilities.
[ { "created": "Thu, 1 Feb 2007 17:51:17 GMT", "version": "v1" } ]
2008-11-26
[ [ "Venugopalan", "Raju", "" ] ]
We discuss the relation between multi-particle production in the Glasma at next-to-leading order and the physics of plasma instabilities.
2212.03400
Jos\'e Nicasio
Jos\'e Nicasio, Ulrich D. Jentschura
Dispersion of Ultra-Relativistic Tardyonic and Tachyonic Wave Packets on Cosmic Scales
Published in journal "Symmetry" in the special issue on "Tachyons and Fundamental Symmetries"
Symmetry 14, 2596 (2022)
10.3390/sym14122596
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the time propagation of tachyonic (superluminal) and tardyonic (subluminal, ordinary) massive wave packets on cosmic scales. A normalizable wave packet cannot be monochromatic in momentum space and thus acquires a positional uncertainty (or packet width) that increases with travel distance. We investigate the question of how this positional uncertainty affects the uncertainty in the detection time for cosmic radiation on Earth. In the ultrarelativistic limit, we find a unified result, $\delta x(t)/c^3 = m^2 \delta p t /p_0^3$, where $\delta x(t)$ is the positional uncertainty, $m$ is the mass parameter, $\delta p$ is the initial momentum spread of the wave function, and $p_0$ is the central momentum of the wave packet, which, in the ultrarelativistic limit, is equal to its energy. This result is valid for tachyons and tardyons; its interpretation is being discussed.
[ { "created": "Wed, 7 Dec 2022 01:47:47 GMT", "version": "v1" }, { "created": "Mon, 12 Dec 2022 20:30:24 GMT", "version": "v2" } ]
2022-12-14
[ [ "Nicasio", "José", "" ], [ "Jentschura", "Ulrich D.", "" ] ]
We investigate the time propagation of tachyonic (superluminal) and tardyonic (subluminal, ordinary) massive wave packets on cosmic scales. A normalizable wave packet cannot be monochromatic in momentum space and thus acquires a positional uncertainty (or packet width) that increases with travel distance. We investigate the question of how this positional uncertainty affects the uncertainty in the detection time for cosmic radiation on Earth. In the ultrarelativistic limit, we find a unified result, $\delta x(t)/c^3 = m^2 \delta p t /p_0^3$, where $\delta x(t)$ is the positional uncertainty, $m$ is the mass parameter, $\delta p$ is the initial momentum spread of the wave function, and $p_0$ is the central momentum of the wave packet, which, in the ultrarelativistic limit, is equal to its energy. This result is valid for tachyons and tardyons; its interpretation is being discussed.
hep-ph/9810532
Vicent Gimenez Gomez
V. Gimenez
New Results From Lattice QCD: Non-Perturbative Renormalization and Quark Masses
4 pages, 2 figures. Invited talk given at the QCD 98 Euroconference, Montpellier, France, 2-8 July 1998
Nucl.Phys.Proc.Suppl. 74 (1999) 296-299
10.1016/S0920-5632(99)00181-4
null
hep-ph
null
For the first time, we compute non-perturbatively, i.e. without lattice perturbation theory, the renormalization constants of two-fermion operators in the quenched approximation at $\beta=6.0$, 6.2 and 6.4 using the Wilson and the tree-level improved SW-Clover actions. We apply these renormalization constants to fully non-perturbatively estimate quark masses in the $\bar{MS}$ scheme from lattice simulations of both the hadron spectrum and the Axial Ward Identity in the quenched approximation. Some very preliminary unquenched Wilson results obtained from the gluon configurations generated by the T$\chi$L Collaboration at $\beta=5.6$ and $N_{f}=2$ are also discussed.
[ { "created": "Thu, 29 Oct 1998 18:22:20 GMT", "version": "v1" } ]
2009-10-31
[ [ "Gimenez", "V.", "" ] ]
For the first time, we compute non-perturbatively, i.e. without lattice perturbation theory, the renormalization constants of two-fermion operators in the quenched approximation at $\beta=6.0$, 6.2 and 6.4 using the Wilson and the tree-level improved SW-Clover actions. We apply these renormalization constants to fully non-perturbatively estimate quark masses in the $\bar{MS}$ scheme from lattice simulations of both the hadron spectrum and the Axial Ward Identity in the quenched approximation. Some very preliminary unquenched Wilson results obtained from the gluon configurations generated by the T$\chi$L Collaboration at $\beta=5.6$ and $N_{f}=2$ are also discussed.
2402.14054
Masaki Yamada
Kyohei Mukaida and Masaki Yamada
Perturbative reheating and thermalization of pure Yang-Mills plasma
21 pages, 4 figures
null
null
KEK-TH-2602, TU-1224
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the thermalization of high-energy particles injected from the perturbative decay of inflaton during the pre-thermal phase of reheating in detail. In general, thermalization takes a relatively long time in a low-temperature plasma; therefore, the instantaneous thermalization approximation is not justified, even for the reheating of the Standard Model (SM) sector. We consider a pure Yang-Mills (YM) theory as an approximation of the SM sector or a possible dark sector, considering the Landau-Pomeranchuk-Migdal effect, a quantum interference effect in a finite temperature plasma. We perform the first numerical calculation to solve the time evolution of the system, including the redshift due to the expansion of the Universe, and show the details of the temperature evolution near the maximum and the behavior of the quasi-attractors at later times. The maximal temperature $T_\text{max}$ and time scale $t_\text{max}$ are determined quantitatively, such as $T_\text{max} \simeq 0.05 \times (\Gamma_I M_\text{Pl}^2/m_I^3)^{2/5} m_I$ and $t_\text{max} \simeq 2 \times 10^3 \times (\Gamma_I M_\text{Pl}^2/m_I^3)^{-3/5} m_I^{-1}$ in the SM-like system, where $m_I$ and $\Gamma_I$ are the mass and decay rate of inflaton. We also provide a similar formula for pure $\operatorname*{SU}(N)$ and $\operatorname*{SO}(N)$ YM theories for general values of $N$ and coupling constant $\alpha$, including $T_\text{max} \propto \alpha^{4/5}$ and $t_\text{max} \propto N^{-2} \alpha^{-16/5}$ behaviors and their numerical coefficients. The thermalization occurs in a finite time scale, resulting in a lower maximal temperature of the Universe after inflation than that under the instantaneous thermalization approximation.
[ { "created": "Wed, 21 Feb 2024 19:00:00 GMT", "version": "v1" } ]
2024-02-23
[ [ "Mukaida", "Kyohei", "" ], [ "Yamada", "Masaki", "" ] ]
We investigate the thermalization of high-energy particles injected from the perturbative decay of inflaton during the pre-thermal phase of reheating in detail. In general, thermalization takes a relatively long time in a low-temperature plasma; therefore, the instantaneous thermalization approximation is not justified, even for the reheating of the Standard Model (SM) sector. We consider a pure Yang-Mills (YM) theory as an approximation of the SM sector or a possible dark sector, considering the Landau-Pomeranchuk-Migdal effect, a quantum interference effect in a finite temperature plasma. We perform the first numerical calculation to solve the time evolution of the system, including the redshift due to the expansion of the Universe, and show the details of the temperature evolution near the maximum and the behavior of the quasi-attractors at later times. The maximal temperature $T_\text{max}$ and time scale $t_\text{max}$ are determined quantitatively, such as $T_\text{max} \simeq 0.05 \times (\Gamma_I M_\text{Pl}^2/m_I^3)^{2/5} m_I$ and $t_\text{max} \simeq 2 \times 10^3 \times (\Gamma_I M_\text{Pl}^2/m_I^3)^{-3/5} m_I^{-1}$ in the SM-like system, where $m_I$ and $\Gamma_I$ are the mass and decay rate of inflaton. We also provide a similar formula for pure $\operatorname*{SU}(N)$ and $\operatorname*{SO}(N)$ YM theories for general values of $N$ and coupling constant $\alpha$, including $T_\text{max} \propto \alpha^{4/5}$ and $t_\text{max} \propto N^{-2} \alpha^{-16/5}$ behaviors and their numerical coefficients. The thermalization occurs in a finite time scale, resulting in a lower maximal temperature of the Universe after inflation than that under the instantaneous thermalization approximation.
hep-ph/9704294
null
C.S.Lim (Kobe univ)
Quaternionic Mass Matrices and CP Symmetry
10 pages, LaTex
Mod.Phys.Lett. A12 (1997) 2829-2836
10.1142/S0217732397002958
KOBE-TH-95-06
hep-ph
null
A viable formulation of gauge theory with extra generations in terms of quaternionic fields is presented. For the theory to be acceptable, the number of generations should be equal to or greater than 4. The quark-lepton mass matrices are generalized into quaternionic matrices.It is concluded that explicit CP violation automatically disappears in both strong- and weak-interaction sectors.
[ { "created": "Fri, 11 Apr 1997 08:21:29 GMT", "version": "v1" } ]
2009-10-30
[ [ "Lim", "C. S.", "", "Kobe univ" ] ]
A viable formulation of gauge theory with extra generations in terms of quaternionic fields is presented. For the theory to be acceptable, the number of generations should be equal to or greater than 4. The quark-lepton mass matrices are generalized into quaternionic matrices.It is concluded that explicit CP violation automatically disappears in both strong- and weak-interaction sectors.
hep-ph/9905354
Thomas Hahn
T. Hahn
Generating and Calculating One-loop Feynman Diagrams with FeynArts, FormCalc, and LoopTools
LaTeX, 5 pages, uses axodraw. Talk given at AIHENP 99, Heraklion, Crete, April 1999
null
null
KA-TP-5-1999
hep-ph
null
A set of programs is presented for automatically generating and calculating Feynman diagrams. Diagrams are generated with FeynArts, then algebraically simplified using a combination of Mathematica and FORM implemented in the package FormCalc, and finally evaluated numerically using the LoopTools package. FormCalc works either in dimensional regularization or in constrained differential renormalization, the latter of which is equivalent at the one-loop level to regularization by dimensional reduction. FormCalc combines the speed of FORM with the powerful instruction set of Mathematica, and the latter greatly eases further processing of the results (e.g. selecting or modifying terms). The output is in a form well suited for numerical evaluation, which is then straightforward using the implementations of the one-loop integrals in LoopTools.
[ { "created": "Sat, 15 May 1999 14:48:18 GMT", "version": "v1" } ]
2007-05-23
[ [ "Hahn", "T.", "" ] ]
A set of programs is presented for automatically generating and calculating Feynman diagrams. Diagrams are generated with FeynArts, then algebraically simplified using a combination of Mathematica and FORM implemented in the package FormCalc, and finally evaluated numerically using the LoopTools package. FormCalc works either in dimensional regularization or in constrained differential renormalization, the latter of which is equivalent at the one-loop level to regularization by dimensional reduction. FormCalc combines the speed of FORM with the powerful instruction set of Mathematica, and the latter greatly eases further processing of the results (e.g. selecting or modifying terms). The output is in a form well suited for numerical evaluation, which is then straightforward using the implementations of the one-loop integrals in LoopTools.
2201.09253
Yu. A. Simonov
Yu.A.Simonov
Quark condensate in QCD at nonzero magnetic field and temperature
15 pages,5 tables
null
10.1134/S106377882205009X
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The basic form of the quark condensate for arbitrary values of external magnetic field and temperature, is derived using the field equations with account of confinement. The resulting expression of the chiral condensate is shown to be proportional to square of the singlet $q\bar q$ ground state wave function at origin, $|\phi_0(0)|^2$. For light quarks without magnetic field the condensates are proportional to $\sigma^{3/2}$ ($\sigma$ is the string tension). Numerical results are presented in 5 Tables and shown to be in good agreement with the lattice data, both for nonzero magnetic field $eB$ and temperature $T$ in the range $0 <T < 120$~MeV,~ $0 <eB <4$~GeV$^2$.
[ { "created": "Sun, 23 Jan 2022 12:43:53 GMT", "version": "v1" }, { "created": "Mon, 31 Jan 2022 10:43:38 GMT", "version": "v2" }, { "created": "Mon, 14 Feb 2022 09:55:37 GMT", "version": "v3" } ]
2022-11-23
[ [ "Simonov", "Yu. A.", "" ] ]
The basic form of the quark condensate for arbitrary values of external magnetic field and temperature, is derived using the field equations with account of confinement. The resulting expression of the chiral condensate is shown to be proportional to square of the singlet $q\bar q$ ground state wave function at origin, $|\phi_0(0)|^2$. For light quarks without magnetic field the condensates are proportional to $\sigma^{3/2}$ ($\sigma$ is the string tension). Numerical results are presented in 5 Tables and shown to be in good agreement with the lattice data, both for nonzero magnetic field $eB$ and temperature $T$ in the range $0 <T < 120$~MeV,~ $0 <eB <4$~GeV$^2$.
hep-ph/0212156
Alexandr Dorokhov
A.E. Dorokhov
Pion distribution amplitudes within the instanton model of QCD vacuum
5 pages, 4 eps figures. Revised version: references and figures added
JETP Lett. 77 (2003) 63-67; Pisma Zh.Eksp.Teor.Fiz. 77 (2003) 68-72
10.1134/1.1564221
null
hep-ph
null
Pion transition form factor for the process $\gamma*\gamma*\to \pi^0$ at space-like values of photon momenta is calculated within the effective quark-meson model with the interaction induced by instanton exchange. The leading and next-to-leading order power asymptotics of the form factor and the relation between the light-cone pion distribution amplitudes of twists 2 and 4 and the dynamically generated quark mass are found.
[ { "created": "Wed, 11 Dec 2002 17:17:34 GMT", "version": "v1" }, { "created": "Sun, 29 Dec 2002 13:39:25 GMT", "version": "v2" } ]
2014-11-17
[ [ "Dorokhov", "A. E.", "" ] ]
Pion transition form factor for the process $\gamma*\gamma*\to \pi^0$ at space-like values of photon momenta is calculated within the effective quark-meson model with the interaction induced by instanton exchange. The leading and next-to-leading order power asymptotics of the form factor and the relation between the light-cone pion distribution amplitudes of twists 2 and 4 and the dynamically generated quark mass are found.
1301.0493
Gionata Luisoni
H. van Deurzen, N. Greiner, G. Luisoni, P. Mastrolia, E. Mirabella, G. Ossola, T. Peraro, J. F. von Soden-Fraunhofen, F. Tramontano
NLO QCD corrections to the production of Higgs plus two jets at the LHC
9 pages, 7 figures, references added, published in Phys.Lett.B
Phys.Lett. B721 (2013) 74-81
10.1016/j.physletb.2013.02.051
DSF-03-2013, MPP-2013-36
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the calculation of the NLO QCD corrections to the associated production of a Higgs boson and two jets, in the infinite top-mass limit. We discuss the technical details of the computation and we show the numerical impact of the radiative corrections on several observables at the LHC. The results are obtained by using a fully automated framework for fixed order NLO QCD calculations based on the interplay of the packages GoSam and Sherpa. The evaluation of the virtual corrections constitutes an application of the d-dimensional integrand-level reduction to theories with higher dimensional operators. We also present first results for the one-loop matrix elements of the partonic processes with a quark-pair in the final state, which enter the hadronic production of a Higgs boson together with three jets in the infinite top-mass approximation.
[ { "created": "Thu, 3 Jan 2013 16:20:28 GMT", "version": "v1" }, { "created": "Sun, 26 May 2013 17:01:20 GMT", "version": "v2" } ]
2013-05-28
[ [ "van Deurzen", "H.", "" ], [ "Greiner", "N.", "" ], [ "Luisoni", "G.", "" ], [ "Mastrolia", "P.", "" ], [ "Mirabella", "E.", "" ], [ "Ossola", "G.", "" ], [ "Peraro", "T.", "" ], [ "von Soden-Fraunh...
We present the calculation of the NLO QCD corrections to the associated production of a Higgs boson and two jets, in the infinite top-mass limit. We discuss the technical details of the computation and we show the numerical impact of the radiative corrections on several observables at the LHC. The results are obtained by using a fully automated framework for fixed order NLO QCD calculations based on the interplay of the packages GoSam and Sherpa. The evaluation of the virtual corrections constitutes an application of the d-dimensional integrand-level reduction to theories with higher dimensional operators. We also present first results for the one-loop matrix elements of the partonic processes with a quark-pair in the final state, which enter the hadronic production of a Higgs boson together with three jets in the infinite top-mass approximation.
2205.12273
Nicol\`o Foppiani
Carlos A. Arg\"uelles, Nicol\`o Foppiani, Matheus Hostert
Efficiently Exploring Multi-Dimensional Parameter Spaces Beyond the Standard Model
19 pages, 15 figures
null
10.1103/PhysRevD.107.035027
null
hep-ph hep-ex
http://creativecommons.org/licenses/by-nc-nd/4.0/
We propose a method to ease the challenges of exploring multi-dimensional parameter spaces in beyond-the-Standard Model theories. We evaluate the model likelihood for any choice of parameters by sampling the theory parameters intelligently and building a Kernel Density Estimator. By reducing the number of expensive Monte-Carlo simulations, this method provides a more efficient way to test complex theories. We illustrate our technique to set new limits on a short-lived heavy neutrino $N$, proposed as an explanation of anomalies in neutrino experiments. Using a search for lepton pairs in the T2K near detector, we find exclusion limits on the model parameters in a vast region of parameter space, fully exploiting the advantages of our new method. With a single Monte Carlo simulation, we obtain the differential event rate for arbitrary choices of model parameters, allowing us to cast limits on any slice of the model parameter space. We conclude that $N$ particles with lifetimes greater than $c \tau^0 \gtrsim 3~$cm are excluded by T2K data. We also derive model-independent constraints in terms of the total rate, lifetime, and $N$ mass and provide an approximated analytical formula. This method can be applied in other branches of physics to explore the landscape of theory parameters efficiently.
[ { "created": "Tue, 24 May 2022 18:00:00 GMT", "version": "v1" }, { "created": "Fri, 19 Aug 2022 09:21:40 GMT", "version": "v2" } ]
2023-03-08
[ [ "Argüelles", "Carlos A.", "" ], [ "Foppiani", "Nicolò", "" ], [ "Hostert", "Matheus", "" ] ]
We propose a method to ease the challenges of exploring multi-dimensional parameter spaces in beyond-the-Standard Model theories. We evaluate the model likelihood for any choice of parameters by sampling the theory parameters intelligently and building a Kernel Density Estimator. By reducing the number of expensive Monte-Carlo simulations, this method provides a more efficient way to test complex theories. We illustrate our technique to set new limits on a short-lived heavy neutrino $N$, proposed as an explanation of anomalies in neutrino experiments. Using a search for lepton pairs in the T2K near detector, we find exclusion limits on the model parameters in a vast region of parameter space, fully exploiting the advantages of our new method. With a single Monte Carlo simulation, we obtain the differential event rate for arbitrary choices of model parameters, allowing us to cast limits on any slice of the model parameter space. We conclude that $N$ particles with lifetimes greater than $c \tau^0 \gtrsim 3~$cm are excluded by T2K data. We also derive model-independent constraints in terms of the total rate, lifetime, and $N$ mass and provide an approximated analytical formula. This method can be applied in other branches of physics to explore the landscape of theory parameters efficiently.
2406.08550
Daniel Pablos
Daniel Pablos and Sergio Sanjurjo
Color Coherence Effects in Dipole-Quark Scattering in the Soft Limit
7 pages, 2 figures, version submitted to journal
null
null
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
Color coherence effects play a crucial role in the description of jet evolution at collider experiments. It is well known that the stimulated gluon emission suffered by energetic jets traversing deconfined QCD matter is also affected by color coherence effects. Through multiple soft scatterings with the medium constituents, an antenna will lose its color correlation, causing its legs to behave as independent emitters after the so-called decoherence time. In this work we provide the first computation of the properties of the recoils produced as a result of these soft scatterings between a color coherent dipole and the medium constituents. Our findings reveal that the angular phase-space of these soft recoils is strongly restricted by the opening angle of the dipole itself due to quantum interference effects. In this long wavelength limit, one can effectively consider that interactions take place with each of the legs of the dipole separately, provided that the angular constraints dictated by the corresponding color flow topologies are respected. This is in complete analogy with the case of soft gluon emission in vacuum, where the recoil quark plays the role of the emitted gluon. As a direct phenomenological application we estimate the collisional energy loss rate of a color antenna. Importantly, these results indicate the way in which color coherence effects can be implemented in jet quenching models that account for the recoils from elastic scatterings, improving in this way our description of medium response physics in heavy-ion collisions.
[ { "created": "Wed, 12 Jun 2024 18:00:06 GMT", "version": "v1" }, { "created": "Sat, 29 Jun 2024 00:21:49 GMT", "version": "v2" } ]
2024-07-02
[ [ "Pablos", "Daniel", "" ], [ "Sanjurjo", "Sergio", "" ] ]
Color coherence effects play a crucial role in the description of jet evolution at collider experiments. It is well known that the stimulated gluon emission suffered by energetic jets traversing deconfined QCD matter is also affected by color coherence effects. Through multiple soft scatterings with the medium constituents, an antenna will lose its color correlation, causing its legs to behave as independent emitters after the so-called decoherence time. In this work we provide the first computation of the properties of the recoils produced as a result of these soft scatterings between a color coherent dipole and the medium constituents. Our findings reveal that the angular phase-space of these soft recoils is strongly restricted by the opening angle of the dipole itself due to quantum interference effects. In this long wavelength limit, one can effectively consider that interactions take place with each of the legs of the dipole separately, provided that the angular constraints dictated by the corresponding color flow topologies are respected. This is in complete analogy with the case of soft gluon emission in vacuum, where the recoil quark plays the role of the emitted gluon. As a direct phenomenological application we estimate the collisional energy loss rate of a color antenna. Importantly, these results indicate the way in which color coherence effects can be implemented in jet quenching models that account for the recoils from elastic scatterings, improving in this way our description of medium response physics in heavy-ion collisions.
1711.07416
Mubarak Alqahtani
Mubarak Alqahtani, Mohammad Nopoush, Radoslaw Ryblewski, and Michael Strickland
Quasiparticle anisotropic hydrodynamics for ultrarelativistic heavy-ion collisions
Proceedings of Critical Point and Onset of Deconfinement - CPOD2017, 7-11 August, 2017. To be published in PoS
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this proceedings contribution, we will review the basics of quasiparticle anisotropic hydrodynamics. Then, we will present some recent phenomenological results of 3+1d quasiparticle anisotropic hydrodynamics and Pb-Pb $2.76$ TeV collisions from the ALICE collaboration. We show that 3+1d quasiparticle anisotropic hydrodynamics model is able to describe the experimental results for Pb-Pb collisions at $2.76$ TeV quite well for many observables such as the spectra, the elliptic flow, and HBT radii in many centrality classes.
[ { "created": "Mon, 20 Nov 2017 17:13:43 GMT", "version": "v1" } ]
2017-11-21
[ [ "Alqahtani", "Mubarak", "" ], [ "Nopoush", "Mohammad", "" ], [ "Ryblewski", "Radoslaw", "" ], [ "Strickland", "Michael", "" ] ]
In this proceedings contribution, we will review the basics of quasiparticle anisotropic hydrodynamics. Then, we will present some recent phenomenological results of 3+1d quasiparticle anisotropic hydrodynamics and Pb-Pb $2.76$ TeV collisions from the ALICE collaboration. We show that 3+1d quasiparticle anisotropic hydrodynamics model is able to describe the experimental results for Pb-Pb collisions at $2.76$ TeV quite well for many observables such as the spectra, the elliptic flow, and HBT radii in many centrality classes.
hep-ph/9308338
null
A. Djouadi and P. Gambino
On the asymptotic ${\cal O}(\alpha \alpha_S)$ behavior of the electroweak gauge bosons vacuum polarization functions for arbitrary quark masses
14 pages + 2 figures (not included: available by mail from A. Djouadi), Preprint UdeM-LPN-TH-93-156 and NYU-TH-93/05/02
Phys.Rev. D49 (1994) 4705-4712
10.1103/PhysRevD.49.4705
null
hep-ph
null
We derive the QCD corrections to the electroweak gauge bosons vacuum polarization functions at high and zero--momentum transfer in the case of arbitrary internal quark masses. We then discuss in this general case (i) the connection between the $O(\alpha \alpha_S)$ calculations of the vector bosons self--energies using dimensional regularization and the one performed via a dispersive approach and (ii) the QCD corrections to the $\rho$ parameter for a heavy quark isodoublet.
[ { "created": "Wed, 25 Aug 1993 20:20:47 GMT", "version": "v1" } ]
2009-10-22
[ [ "Djouadi", "A.", "" ], [ "Gambino", "P.", "" ] ]
We derive the QCD corrections to the electroweak gauge bosons vacuum polarization functions at high and zero--momentum transfer in the case of arbitrary internal quark masses. We then discuss in this general case (i) the connection between the $O(\alpha \alpha_S)$ calculations of the vector bosons self--energies using dimensional regularization and the one performed via a dispersive approach and (ii) the QCD corrections to the $\rho$ parameter for a heavy quark isodoublet.
hep-ph/0207366
Michele Frigerio
M. Frigerio (SISSA & INFN, Trieste) and A.Yu. Smirnov (ICTP, Trieste & INR, Moscow)
Neutrino mass matrix: inverted hierarchy and CP violation
35 pages, 7 eps figures, typos corrected, some clarifications added
Phys.Rev. D67 (2003) 013007
10.1103/PhysRevD.67.013007
SISSA 57/2002/EP
hep-ph
null
We reconstruct the neutrino mass matrix in flavor basis, in the case of inverted mass hierarchy (ordering), using all available experimental data on neutrino masses and oscillations. We analyze the dependence of the matrix elements m_{alpha beta} on the CP violating Dirac, delta, and Majorana, rho and sigma, phases, for different values of the absolute mass scale. We find that the present data admit various structures of the mass matrix: (i) hierarchical structures with a set of small (zero) elements; (ii) structures with equalities among various groups of elements: e-row and/or mu tau-block elements, diagonal and/or off-diagonal elements; (iii) ``democratic'' structure. We find values of phases for which these structures are realized. The mass matrix elements can anti-correlate with flavor: inverted partial or complete flavor alignment is possible. For various structures of the mass matrix we identify possible underlying symmetry. We find that the mass matrix can be reconstructed completely only in particular cases, provided that the absolute scale of the mass is measured. Generally, the freedom related to the Majorana phase sigma will not be removed, thus admitting various types of mass matrix.
[ { "created": "Wed, 31 Jul 2002 15:43:08 GMT", "version": "v1" }, { "created": "Thu, 19 Dec 2002 18:55:55 GMT", "version": "v2" } ]
2009-11-07
[ [ "Frigerio", "M.", "", "SISSA & INFN, Trieste" ], [ "Smirnov", "A. Yu.", "", "ICTP, Trieste &\n INR, Moscow" ] ]
We reconstruct the neutrino mass matrix in flavor basis, in the case of inverted mass hierarchy (ordering), using all available experimental data on neutrino masses and oscillations. We analyze the dependence of the matrix elements m_{alpha beta} on the CP violating Dirac, delta, and Majorana, rho and sigma, phases, for different values of the absolute mass scale. We find that the present data admit various structures of the mass matrix: (i) hierarchical structures with a set of small (zero) elements; (ii) structures with equalities among various groups of elements: e-row and/or mu tau-block elements, diagonal and/or off-diagonal elements; (iii) ``democratic'' structure. We find values of phases for which these structures are realized. The mass matrix elements can anti-correlate with flavor: inverted partial or complete flavor alignment is possible. For various structures of the mass matrix we identify possible underlying symmetry. We find that the mass matrix can be reconstructed completely only in particular cases, provided that the absolute scale of the mass is measured. Generally, the freedom related to the Majorana phase sigma will not be removed, thus admitting various types of mass matrix.
0911.0620
Sarah Heim
Sarah Heim, Qing-Hong Cao, Reinhard Schwienhorst, and C.-P. Yuan
Next-to-leading order QCD corrections to s-channel single top quark production and decay at the LHC
39 pages, 27 figures but 74 figure files (because of subfigures), replacement because of minor changes like added references and typos
Phys.Rev.D81:034005,2010
10.1103/PhysRevD.81.034005
ANL-HEP-PR-09-94, EFI-09-22, MSUHEP-091025
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a study of electroweak production of top and antitop quarks in the s-channel mode at the LHC, including next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to the production and decay of the single (anti)top quark. The spin is preserved in production and decay by using the narrow width approximation for the (anti)top quark. We show the effect of different O(alpha_s) contributions on the inclusive cross section and various kinematic distributions at parton level after imposing relevant kinematic cuts to select s-channel single top quark events. We also discuss several possibilities for measuring the top quark polarization.
[ { "created": "Tue, 3 Nov 2009 17:15:55 GMT", "version": "v1" }, { "created": "Tue, 9 Feb 2010 16:49:01 GMT", "version": "v2" } ]
2010-04-29
[ [ "Heim", "Sarah", "" ], [ "Cao", "Qing-Hong", "" ], [ "Schwienhorst", "Reinhard", "" ], [ "Yuan", "C. -P.", "" ] ]
We present a study of electroweak production of top and antitop quarks in the s-channel mode at the LHC, including next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to the production and decay of the single (anti)top quark. The spin is preserved in production and decay by using the narrow width approximation for the (anti)top quark. We show the effect of different O(alpha_s) contributions on the inclusive cross section and various kinematic distributions at parton level after imposing relevant kinematic cuts to select s-channel single top quark events. We also discuss several possibilities for measuring the top quark polarization.
1208.4965
Jian Zhou Mr.
Emin Akcakaya, Andreas Sch\"afer and Jian Zhou
Azimuthal asymmetries for quark pair production in pA collisions
17 pages, 3 figures
null
10.1103/PhysRevD.87.054010
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the azimuthal asymmetries for quark pair production in proton-nucleus collisions using a hybrid approach in which the nucleus is treated in the Color Glass Condensate (CGC) framework while the Lipatov approximation is applied on the proton side. Our treatment goes beyond the large N_c limit. We particularly focus on the so-called correlation limit where the imbalance of the transverse momentum of the quark pair is much smaller than the out-going individual quark transverse momenta. In this kinematic region, a matching between the hybrid approach and a factorization in terms of transverse momentum dependent parton distributions(TMDs) has been found. It is shown which of the various unpolarized and linearly polarized gluon TMD distributions contribute to $\cos 2 \phi$ and $\cos 4 \phi$ modulations of quark pair production.
[ { "created": "Fri, 24 Aug 2012 12:52:22 GMT", "version": "v1" }, { "created": "Wed, 27 Feb 2013 18:28:13 GMT", "version": "v2" } ]
2013-03-14
[ [ "Akcakaya", "Emin", "" ], [ "Schäfer", "Andreas", "" ], [ "Zhou", "Jian", "" ] ]
We study the azimuthal asymmetries for quark pair production in proton-nucleus collisions using a hybrid approach in which the nucleus is treated in the Color Glass Condensate (CGC) framework while the Lipatov approximation is applied on the proton side. Our treatment goes beyond the large N_c limit. We particularly focus on the so-called correlation limit where the imbalance of the transverse momentum of the quark pair is much smaller than the out-going individual quark transverse momenta. In this kinematic region, a matching between the hybrid approach and a factorization in terms of transverse momentum dependent parton distributions(TMDs) has been found. It is shown which of the various unpolarized and linearly polarized gluon TMD distributions contribute to $\cos 2 \phi$ and $\cos 4 \phi$ modulations of quark pair production.
1207.6556
Bastian Kubis
E. Czerwinski, S. Eidelman, C. Hanhart, B. Kubis, A. Kupsc, S. Leupold, P. Moskal, S. Schadmand
MesonNet Workshop on Meson Transition Form Factors
69 pages, 14 figures; all talks can be found at https://sites.google.com/site/mesonnetwork/home/activities/form-factor-workshop-2012; v2: workshop link updated (as the page had to be moved to a commercial server), table 6 corrected
null
null
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The mini-proceedings of the Workshop on Meson Transition Form Factors held in Cracow from May 29th to 30th, 2012 introduce the meson transition form factor project with special emphasis on the interrelations between the various form factors (on-shell, single off-shell, double off-shell). Short summaries of the talks presented at the workshop follow.
[ { "created": "Fri, 27 Jul 2012 14:40:02 GMT", "version": "v1" }, { "created": "Fri, 12 Jul 2013 15:31:01 GMT", "version": "v2" } ]
2013-07-15
[ [ "Czerwinski", "E.", "" ], [ "Eidelman", "S.", "" ], [ "Hanhart", "C.", "" ], [ "Kubis", "B.", "" ], [ "Kupsc", "A.", "" ], [ "Leupold", "S.", "" ], [ "Moskal", "P.", "" ], [ "Schadmand", "S.", ...
The mini-proceedings of the Workshop on Meson Transition Form Factors held in Cracow from May 29th to 30th, 2012 introduce the meson transition form factor project with special emphasis on the interrelations between the various form factors (on-shell, single off-shell, double off-shell). Short summaries of the talks presented at the workshop follow.
hep-ph/9503438
Dr Georg Raffelt
Alexandre D.~Dolgov, (Univ. de Valencia) and Georg G.~Raffelt (MPI f. Physik, Munich)
Screening of Long-Range Leptonic Forces by Cosmic Background Neutrinos
REVTeX 3.0 document, 6 pages, no figures.
Phys.Rev.D52:2581-2582,1995
10.1103/PhysRevD.52.2581
null
hep-ph
null
The absence of dispersion effects of the SN~1987A neutrino pulse has been used to constrain novel long-range forces between neutrinos and galactic baryonic or non-baryonic matter. If these forces are mediated by vector bosons, screening effects by the cosmic neutrino background invalidate the SN~1987A limits and other related arguments.
[ { "created": "Sun, 26 Mar 1995 15:57:36 GMT", "version": "v1" } ]
2010-11-30
[ [ "~Dolgov", "Alexandre D.", "", "MPI f.\n Physik, Munich" ], [ "~Raffelt", "Georg G.", "", "MPI f.\n Physik, Munich" ] ]
The absence of dispersion effects of the SN~1987A neutrino pulse has been used to constrain novel long-range forces between neutrinos and galactic baryonic or non-baryonic matter. If these forces are mediated by vector bosons, screening effects by the cosmic neutrino background invalidate the SN~1987A limits and other related arguments.
hep-ph/0504072
Vishnu Bannur M
Vishnu M. Bannur
Strongly Coupled Quark Gluon Plasma (SCQGP)
Revised with corrections and new results, Latex file (11 pages), postscript file of 7 figures
J.Phys. G32 (2006) 993-1002
10.1088/0954-3899/32/7/008
null
hep-ph
null
We propose that the reason for the non-ideal behavior seen in lattice simulation of quark gluon plasma (QGP) and relativistic heavy ion collisions (URHICs) experiments is that the QGP near T_c and above is strongly coupled plasma (SCP), i.e., strongly coupled quark gluon plasma (SCQGP). It is remarkable that the widely used equation of state (EoS) of SCP in QED (quantum electrodynamics) very nicely fits lattice results on all QGP systems, with proper modifications to include color degrees of freedom and running coupling constant. Results on pressure in pure gauge, 2-flavors and 3-flavors QGP, are all can be explained by treating QGP as SCQGP as demonstated here.Energy density and speed of sound are also presented for all three systems. We further extend the model to systems with finite quark mass and a reasonably good fit to lattice results are obtained for (2+1)-flavors and 4-flavors QGP. Hence it is the first unified model, namely SCQGP, to explain the non-ideal QGP seen in lattice simulations with just two system dependent parameters.
[ { "created": "Sat, 9 Apr 2005 10:13:00 GMT", "version": "v1" }, { "created": "Mon, 7 Nov 2005 06:26:41 GMT", "version": "v2" } ]
2009-11-11
[ [ "Bannur", "Vishnu M.", "" ] ]
We propose that the reason for the non-ideal behavior seen in lattice simulation of quark gluon plasma (QGP) and relativistic heavy ion collisions (URHICs) experiments is that the QGP near T_c and above is strongly coupled plasma (SCP), i.e., strongly coupled quark gluon plasma (SCQGP). It is remarkable that the widely used equation of state (EoS) of SCP in QED (quantum electrodynamics) very nicely fits lattice results on all QGP systems, with proper modifications to include color degrees of freedom and running coupling constant. Results on pressure in pure gauge, 2-flavors and 3-flavors QGP, are all can be explained by treating QGP as SCQGP as demonstated here.Energy density and speed of sound are also presented for all three systems. We further extend the model to systems with finite quark mass and a reasonably good fit to lattice results are obtained for (2+1)-flavors and 4-flavors QGP. Hence it is the first unified model, namely SCQGP, to explain the non-ideal QGP seen in lattice simulations with just two system dependent parameters.
1109.6723
Wen-long Sang
Hai-Ting Chen, Yu-Qi Chen (Beijing, Inst. Theor. Phys.) and Wen-Long Sang (TPCSF, Beijing and Korea U.)
Relativistic corrections to the semi-inclusive decay of $\bm{\psi}$ and $\bm{\Upsilon}$
26 pages, 4 figures, 3 tables. arXiv admin note: text overlap with arXiv:0707.4056 by other authors
Phys. Rev. D 85, 034017 (2012)
10.1103/PhysRevD.85.034017
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the framework of the nonrelativistic quantum chromodynamics factorization formalism, we study the processes of $\psi(nS)$ and $\Upsilon(nS)$ decay into a lepton pair or a charm pair associated with two jets up to the next-to-leading order in velocity expansion. We present the analytic expressions for the differential decay rate to the invariant mass of the lepton pair or charm pair. We find that the ratio of the next-to-leading order short-distance coefficient to the leading order one is in the range from -5.5 to -12.4. The relativistic corrections are so large that they modify the leading order prediction significantly. Utilizing the analytic expressions, we also investigate the relativistic corrections in different kinematic regions and their dependence on the masses of the initial-state quarkonium and the final-state fermion. In addition, we study the momentum distribution of $D^{*+}$ in the process $\Upsilon(1S)\to c\bar{c}gg\to D^{*+}X$.
[ { "created": "Fri, 30 Sep 2011 06:27:08 GMT", "version": "v1" }, { "created": "Wed, 15 Feb 2012 06:18:41 GMT", "version": "v2" } ]
2015-03-19
[ [ "Chen", "Hai-Ting", "", "Beijing, Inst. Theor. Phys." ], [ "Chen", "Yu-Qi", "", "Beijing, Inst. Theor. Phys." ], [ "Sang", "Wen-Long", "", "TPCSF, Beijing and Korea U." ] ]
In the framework of the nonrelativistic quantum chromodynamics factorization formalism, we study the processes of $\psi(nS)$ and $\Upsilon(nS)$ decay into a lepton pair or a charm pair associated with two jets up to the next-to-leading order in velocity expansion. We present the analytic expressions for the differential decay rate to the invariant mass of the lepton pair or charm pair. We find that the ratio of the next-to-leading order short-distance coefficient to the leading order one is in the range from -5.5 to -12.4. The relativistic corrections are so large that they modify the leading order prediction significantly. Utilizing the analytic expressions, we also investigate the relativistic corrections in different kinematic regions and their dependence on the masses of the initial-state quarkonium and the final-state fermion. In addition, we study the momentum distribution of $D^{*+}$ in the process $\Upsilon(1S)\to c\bar{c}gg\to D^{*+}X$.
2305.11432
Hidetoshi Taya
Kenji Fukushima, Yoshimasa Hidaka, Takuya Shimazaki, Hidetoshi Taya
Chiral anomaly in a (1+1)-dimensional Floquet system under high-frequency electric fields
29 pages; v2: minor changes, to appear in Annals of Physics
null
null
RIKEN-iTHEMS-Report-23, KEK-TH-2528, J-PARC-TH-0289
hep-ph cond-mat.str-el hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the chiral anomaly in a Floquet system under a time-periodic electric field in (1+1) dimensions. Using the van~Vleck high-frequency expansion, we analytically calculate the chiral current and the pseudo-scalar condensate for massless/massive fermions and how they are balanced with the topological charge. In the high-frequency limit, we find that finite-mass effects are suppressed and the topological charge is dominated by the chirality production. Our calculations show that the information about the chiral anomaly is stored not in the static Floquet Hamiltonian but in the periodic kick operator. The computational steps are useful as the theoretical foundation for higher-dimensional generalization.
[ { "created": "Fri, 19 May 2023 05:13:37 GMT", "version": "v1" }, { "created": "Wed, 25 Oct 2023 14:47:07 GMT", "version": "v2" } ]
2023-10-26
[ [ "Fukushima", "Kenji", "" ], [ "Hidaka", "Yoshimasa", "" ], [ "Shimazaki", "Takuya", "" ], [ "Taya", "Hidetoshi", "" ] ]
We investigate the chiral anomaly in a Floquet system under a time-periodic electric field in (1+1) dimensions. Using the van~Vleck high-frequency expansion, we analytically calculate the chiral current and the pseudo-scalar condensate for massless/massive fermions and how they are balanced with the topological charge. In the high-frequency limit, we find that finite-mass effects are suppressed and the topological charge is dominated by the chirality production. Our calculations show that the information about the chiral anomaly is stored not in the static Floquet Hamiltonian but in the periodic kick operator. The computational steps are useful as the theoretical foundation for higher-dimensional generalization.
hep-ph/9304231
null
M. Genovese, D.B. Lichtemberg and E. Predazzi
Phenomenology of Spin Zero Mesons and Glueballs
25 pag, IUHET 248 andDFTT 14/93
null
null
null
hep-ph
null
We discuss the phenomenology of scalar and pseudoscalar mesons, emphasizing those which do not carry manifest flavor quantum numbers. Many of the properties of these mesons are still not fully understood. Some of them probably do not have the usual two-quark (quark-antiquark) structure, but may be mixed with glueball states or other exotics. %, hybrids, or four-quark states. We construct or discuss simple models for these mesons and point out which measurements can shed light on their composition.
[ { "created": "Thu, 8 Apr 1993 10:27:13 GMT", "version": "v1" } ]
2007-05-23
[ [ "Genovese", "M.", "" ], [ "Lichtemberg", "D. B.", "" ], [ "Predazzi", "E.", "" ] ]
We discuss the phenomenology of scalar and pseudoscalar mesons, emphasizing those which do not carry manifest flavor quantum numbers. Many of the properties of these mesons are still not fully understood. Some of them probably do not have the usual two-quark (quark-antiquark) structure, but may be mixed with glueball states or other exotics. %, hybrids, or four-quark states. We construct or discuss simple models for these mesons and point out which measurements can shed light on their composition.
1308.0230
Hiroaki Sugiyama
A.G. Akeroyd, S. Moretti, Hiroaki Sugiyama
Dependence of the leptonic decays of H^- on the neutrino mixing angles theta_{13} and theta_{23} in models with neutrinophilic charged scalars
17 pages, 6 figures
Phys. Lett. B728, 157 (2014)
10.1016/j.physletb.2013.11.032
MISC-2013-06
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the Higgs Triplet Model and the neutrinophilic Two-Higgs-Doublet Model the observed neutrinos obtain mass from a vacuum expectation value which is much smaller than the vacuum expectation value of the Higgs boson in the Standard Model. Both models contain a singly charged Higgs boson (H^-) whose Yukawa coupling is directly related to the neutrino mass (i.e. a "neutrinophilic charged Higgs"). The partial decay widths of H^- into a charged lepton and a neutrino (H^- to l^- nu) depend identically on the neutrino masses and mixings in the two models. We quantify the impact of the recent measurement of sin^2(2theta_{13}), which plays a crucial role in determining the magnitude of the branching ratio of H^- to e^- nu for the case of a normal neutrino mass ordering if the lightest neutrino mass m_0 < 10^{-3} eV. We also discuss the sizeable dependence of H^- to mu^- nu and H^- to tau^- nu on sin^2(theta_{23}), which would enable information to be obtained on sin^2(theta_{23}) and the sign of \Delta m^2_{31} if these decays are measured. Such information would help neutrino oscillation experiments to determine the CP-violating phase \delta.
[ { "created": "Thu, 1 Aug 2013 14:44:43 GMT", "version": "v1" }, { "created": "Thu, 19 Dec 2013 20:26:26 GMT", "version": "v2" } ]
2013-12-20
[ [ "Akeroyd", "A. G.", "" ], [ "Moretti", "S.", "" ], [ "Sugiyama", "Hiroaki", "" ] ]
In the Higgs Triplet Model and the neutrinophilic Two-Higgs-Doublet Model the observed neutrinos obtain mass from a vacuum expectation value which is much smaller than the vacuum expectation value of the Higgs boson in the Standard Model. Both models contain a singly charged Higgs boson (H^-) whose Yukawa coupling is directly related to the neutrino mass (i.e. a "neutrinophilic charged Higgs"). The partial decay widths of H^- into a charged lepton and a neutrino (H^- to l^- nu) depend identically on the neutrino masses and mixings in the two models. We quantify the impact of the recent measurement of sin^2(2theta_{13}), which plays a crucial role in determining the magnitude of the branching ratio of H^- to e^- nu for the case of a normal neutrino mass ordering if the lightest neutrino mass m_0 < 10^{-3} eV. We also discuss the sizeable dependence of H^- to mu^- nu and H^- to tau^- nu on sin^2(theta_{23}), which would enable information to be obtained on sin^2(theta_{23}) and the sign of \Delta m^2_{31} if these decays are measured. Such information would help neutrino oscillation experiments to determine the CP-violating phase \delta.
hep-ph/9504204
Tord Riemann
Dima Bardin, Arnd Leike, Tord Riemann
Higgs production in $e^+ e^- \to l{\bar l} q{\bar q}$ at LEP and NLC
8 pages (LaTeX), 5 figures ( 3 of them not included, a uuencoded file containing the LaTeX and all postscript files is available via anonymous ftp at ftp://ftp.ifh.de/pub/preprint/desy95-057.uu)
Phys.Lett. B353 (1995) 513-518
10.1016/0370-2693(95)00587-B
DESY 95-057
hep-ph
null
Predictions for Higgs production with processes of the type $e^+ e^- \rightarrow \mu{\bar \mu}\;b\bar b $ at LEP~2 and the NLC are calculated. Short analytical formulae describe the double differential distribution in the invariant masses of the $\mu \bar \mu$ and $b \bar{b}$ pairs. The total cross section may be got with two numerical integrations. The various Higgs-background interferences vanish either identically or are small. The background contributions depend strongly on cuts applied on the invariant masses.
[ { "created": "Mon, 3 Apr 1995 15:20:25 GMT", "version": "v1" } ]
2009-10-28
[ [ "Bardin", "Dima", "" ], [ "Leike", "Arnd", "" ], [ "Riemann", "Tord", "" ] ]
Predictions for Higgs production with processes of the type $e^+ e^- \rightarrow \mu{\bar \mu}\;b\bar b $ at LEP~2 and the NLC are calculated. Short analytical formulae describe the double differential distribution in the invariant masses of the $\mu \bar \mu$ and $b \bar{b}$ pairs. The total cross section may be got with two numerical integrations. The various Higgs-background interferences vanish either identically or are small. The background contributions depend strongly on cuts applied on the invariant masses.
1701.04593
Yueling Yang
Yueling Yang, Junfeng Sun, Yan Guo, Qingxia Li, Jinshu Huang, Qin Chang
Study of ${\Upsilon}(nS)$ ${\to}$ $B_{c}P$ decays with perturbative QCD approach
14 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:1610.06986
Physics Letters B 751, 171-176 (2015)
10.1016/j.physletb.2015.10.018
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
With the potential prospects of the ${\Upsilon}(nS)$ at high-luminosity dedicated heavy-flavor factories, the color-favored ${\Upsilon}(nS)$ ${\to}$ $B_{c}{\pi}$, $B_{c}K$ weak decays are studied with the pQCD approach. It is found that branching ratios for the ${\Upsilon}(nS)$ ${\to}$ $B_{c}{\pi}$ decay are as large as the order of ${\cal O}(10^{-11})$, which might be measured promisingly by the future experiments.
[ { "created": "Tue, 17 Jan 2017 09:43:35 GMT", "version": "v1" } ]
2017-02-12
[ [ "Yang", "Yueling", "" ], [ "Sun", "Junfeng", "" ], [ "Guo", "Yan", "" ], [ "Li", "Qingxia", "" ], [ "Huang", "Jinshu", "" ], [ "Chang", "Qin", "" ] ]
With the potential prospects of the ${\Upsilon}(nS)$ at high-luminosity dedicated heavy-flavor factories, the color-favored ${\Upsilon}(nS)$ ${\to}$ $B_{c}{\pi}$, $B_{c}K$ weak decays are studied with the pQCD approach. It is found that branching ratios for the ${\Upsilon}(nS)$ ${\to}$ $B_{c}{\pi}$ decay are as large as the order of ${\cal O}(10^{-11})$, which might be measured promisingly by the future experiments.
1410.3741
Valery Lyubovitskij
Gurjav Ganbold, Thomas Gutsche, Mikhail A. Ivanov, Valery E. Lyubovitskij
On the meson mass spectrum in the covariant confined quark model
12 pages
J. Phys. G: Nucl. Part. Phys. 42 (2015) 075002
10.1088/0954-3899/42/7/075002
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We provide a new insight into the problem of generating the hadron mass spectrum in the framework of the covariant confined quark model. One of the underlying principles of this model is the compositeness condition which means that the wave function renormalization constant of the elementary hadron is equal to zero. In particular, this equation allows to express the Yukawa coupling of the meson fields to the constituent quarks as a function of other model parameters. In addition to the compositeness condition we also employ a further equation which relates the meson mass function to the Fermi coupling. Both equations guarantee that the Yukawa-type theory is equivalent to the Fermi-type theory thereby providing an interpretation of the meson field as the bound state of its constituent fermions (quarks). We evaluate the Fermi-coupling as a function of meson (pseudoscalar and vector) masses and vary the values of the masses in such a way to obtain a smooth behavior for the resulting curve. The mass spectrum obtained in this manner is found to be in good agreement with the experimental data. We also compare the behavior of our Fermi-coupling with the strong QCD coupling alpha_s calculated in an QCD-inspired approach.
[ { "created": "Tue, 14 Oct 2014 16:01:41 GMT", "version": "v1" } ]
2015-06-02
[ [ "Ganbold", "Gurjav", "" ], [ "Gutsche", "Thomas", "" ], [ "Ivanov", "Mikhail A.", "" ], [ "Lyubovitskij", "Valery E.", "" ] ]
We provide a new insight into the problem of generating the hadron mass spectrum in the framework of the covariant confined quark model. One of the underlying principles of this model is the compositeness condition which means that the wave function renormalization constant of the elementary hadron is equal to zero. In particular, this equation allows to express the Yukawa coupling of the meson fields to the constituent quarks as a function of other model parameters. In addition to the compositeness condition we also employ a further equation which relates the meson mass function to the Fermi coupling. Both equations guarantee that the Yukawa-type theory is equivalent to the Fermi-type theory thereby providing an interpretation of the meson field as the bound state of its constituent fermions (quarks). We evaluate the Fermi-coupling as a function of meson (pseudoscalar and vector) masses and vary the values of the masses in such a way to obtain a smooth behavior for the resulting curve. The mass spectrum obtained in this manner is found to be in good agreement with the experimental data. We also compare the behavior of our Fermi-coupling with the strong QCD coupling alpha_s calculated in an QCD-inspired approach.
0805.0401
Wan-lei Guo
Wan-lei Guo, Li-ming Wang, Yue-liang Wu and Ci Zhuang
The Dark Matter Constraints on the Left-Right Symmetric Model with Z_2 Symmetry
25 pages, 4 figures, 5 tables. typos corrected, a figure added, accepted for publication in Physical Review D
Phys.Rev.D78:035015,2008
10.1103/PhysRevD.78.035015
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the framework of Left-Right symmetric model, we investigate an interesting scenario, in which the so-called VEV seesaw problem can be naturally solved with Z_2 symmetry. In such a scenario, we find a pair of stable weakly interacting massive particles (WIMPs), which may be the cold dark matter candidates. However, the WIMP-nucleon cross section is 3-5 orders of magnitude above the present upper bounds from the direct dark matter detection experiments for $m \sim 10^2-10^4 $ GeV. As a result, the relic number density of two stable particles has to be strongly suppressed to a very small level. Nevertheless, our analysis shows that this scenario can't provide very large annihilation cross sections so as to give the desired relic abundance except for the resonance case. Only for the case if the rotation curves of disk galaxies are explained by the Modified Newtonian Dynamics (MOND), the stable WIMPs could be as the candidates of cold dark matter.
[ { "created": "Sun, 4 May 2008 10:38:54 GMT", "version": "v1" }, { "created": "Wed, 6 Aug 2008 11:39:11 GMT", "version": "v2" } ]
2008-11-07
[ [ "Guo", "Wan-lei", "" ], [ "Wang", "Li-ming", "" ], [ "Wu", "Yue-liang", "" ], [ "Zhuang", "Ci", "" ] ]
In the framework of Left-Right symmetric model, we investigate an interesting scenario, in which the so-called VEV seesaw problem can be naturally solved with Z_2 symmetry. In such a scenario, we find a pair of stable weakly interacting massive particles (WIMPs), which may be the cold dark matter candidates. However, the WIMP-nucleon cross section is 3-5 orders of magnitude above the present upper bounds from the direct dark matter detection experiments for $m \sim 10^2-10^4 $ GeV. As a result, the relic number density of two stable particles has to be strongly suppressed to a very small level. Nevertheless, our analysis shows that this scenario can't provide very large annihilation cross sections so as to give the desired relic abundance except for the resonance case. Only for the case if the rotation curves of disk galaxies are explained by the Modified Newtonian Dynamics (MOND), the stable WIMPs could be as the candidates of cold dark matter.
1601.03748
Matthias Steinhauser
Peter Marquard, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser
Four-loop relation between the $\bar{\rm MS}$ and on-shell quark mass
9 pages, 2 figures, to appear in the proceedings of the 12th International Symposium on Radiative Corrections (Radcor 2015) and LoopFest XIV (Radiative Corrections for the LHC and Future Colliders)
null
null
TTP16-003, HU-EP-16/03, DESY 16-006
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this contribution we discuss the four-loop relation between the on-shell and $\bar{\rm MS}$ definition of heavy quark masses which is applied to the top, bottom and charm case. We also present relations between the $\bar{\rm MS}$ quark mass and various threshold mass definitions and discuss the uncertainty at next-to-next-to-next-to-leading order.
[ { "created": "Thu, 14 Jan 2016 21:00:15 GMT", "version": "v1" } ]
2016-01-18
[ [ "Marquard", "Peter", "" ], [ "Smirnov", "Alexander V.", "" ], [ "Smirnov", "Vladimir A.", "" ], [ "Steinhauser", "Matthias", "" ] ]
In this contribution we discuss the four-loop relation between the on-shell and $\bar{\rm MS}$ definition of heavy quark masses which is applied to the top, bottom and charm case. We also present relations between the $\bar{\rm MS}$ quark mass and various threshold mass definitions and discuss the uncertainty at next-to-next-to-next-to-leading order.
hep-ph/9412278
Graciela Gelmini
Graciela Gelmini (UCLA) and Esteban Roulet (CERN)
Neutrino Masses
85 pp.,Tex file requires ioppreprint.sty and verbatim.tex, 12 figures sent separately in a uu-compressed file
Rept.Prog.Phys.58:1207-1266,1995
10.1088/0034-4885/58/10/002
UCLA/94/TEP/36
hep-ph
null
This is a review for Reports of Progress in Physics. After an introduction we start by explaining the different neutrino masses corresponding to different types of neutrinos, Dirac or Majorana, in section 2. In section 3 we discuss the main elementary particle models for neutrino masses and their distinctive phenomenological consequences. In section 4 we describe the status of direct mass searches and Majorana mass searches in neutrinoless double beta decays. In section 5 we go over the many cosmological implications of, and constraints on, neutrino properties, mainly masses and lifetimes. Sections 6, 7 and 8 review neutrino oscillations, the solar neutrino problem and the atmospheric neutrino problem, their implications and the current and future experiments. In particular, we explain oscillations in vacuum in section 6 and oscillations in matter in section 7. Section 9 summarizes the main bounds imposed by stars, mainly SN1987A. A few concluding remarks follow.
[ { "created": "Mon, 12 Dec 1994 22:25:23 GMT", "version": "v1" } ]
2014-11-17
[ [ "Gelmini", "Graciela", "", "UCLA" ], [ "Roulet", "Esteban", "", "CERN" ] ]
This is a review for Reports of Progress in Physics. After an introduction we start by explaining the different neutrino masses corresponding to different types of neutrinos, Dirac or Majorana, in section 2. In section 3 we discuss the main elementary particle models for neutrino masses and their distinctive phenomenological consequences. In section 4 we describe the status of direct mass searches and Majorana mass searches in neutrinoless double beta decays. In section 5 we go over the many cosmological implications of, and constraints on, neutrino properties, mainly masses and lifetimes. Sections 6, 7 and 8 review neutrino oscillations, the solar neutrino problem and the atmospheric neutrino problem, their implications and the current and future experiments. In particular, we explain oscillations in vacuum in section 6 and oscillations in matter in section 7. Section 9 summarizes the main bounds imposed by stars, mainly SN1987A. A few concluding remarks follow.
1801.03073
Stephan Narison
R. Albuquerque (FAT, UERJ, Rio de Janeiro, BR), S. Narison (LUPM-CNRS, Montpellier, FR), D. Rabetiarivony and G. Randriamanatrika (iHEPMAD, Antananarivo, MG)
XYZ - SU3 Breakings from Laplace Sum Rule at Higher Orders: Summary
Part of a review presented by S. Narison @ QCD17 (3-7july 2017, Montpellier-FR) and Talks given by D. Rabetiarivony and G. Randriamanatrika @ HEPMAD17 (21 - 26 September, Antananarivo - MG). To appear in Nucl. Part. Phys. Proc. 8 pages, 6 figures and 7 tables
null
null
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This talk reviews and summarizes some of our results in [1] on XYZ- SU3 Breakings obtained from QCD Laplace Sum Rules (LSR) at next-to-next-leading order (N2LO) of perturbative (PT) theory and including next-to-leading order (NLO) SU3 breaking corrections and leading order (LO) contributions of dimensions d< (6 - 8) non-perturbative condensates. We conclude that the observed X states are good candidates for being 1^++ and 0^++ molecules states. We find that the SU3 breakings are relatively small for the masses (< 10 (resp. 3) %) for the charm (resp. bottom) channels while they are large (< 20 %) for the couplings. Like in the chiral limit case, the couplings decrease faster: 1/m_b^3/2 than 1/m_b^1/2 of HQET. Our approach cannot clearly separate ( within the errors ) some molecule states from the four-quark ones with the same quantum numbers.
[ { "created": "Tue, 9 Jan 2018 18:34:36 GMT", "version": "v1" } ]
2018-01-10
[ [ "Albuquerque", "R.", "", "FAT, UERJ, Rio de Janeiro, BR" ], [ "Narison", "S.", "", "LUPM-CNRS,\n Montpellier, FR" ], [ "Rabetiarivony", "D.", "", "iHEPMAD,\n Antananarivo, MG" ], [ "Randriamanatrika", "G.", "", "iHEPMAD,\n Antananarivo...
This talk reviews and summarizes some of our results in [1] on XYZ- SU3 Breakings obtained from QCD Laplace Sum Rules (LSR) at next-to-next-leading order (N2LO) of perturbative (PT) theory and including next-to-leading order (NLO) SU3 breaking corrections and leading order (LO) contributions of dimensions d< (6 - 8) non-perturbative condensates. We conclude that the observed X states are good candidates for being 1^++ and 0^++ molecules states. We find that the SU3 breakings are relatively small for the masses (< 10 (resp. 3) %) for the charm (resp. bottom) channels while they are large (< 20 %) for the couplings. Like in the chiral limit case, the couplings decrease faster: 1/m_b^3/2 than 1/m_b^1/2 of HQET. Our approach cannot clearly separate ( within the errors ) some molecule states from the four-quark ones with the same quantum numbers.
1810.09260
Kazuo Tsushima
K. Tsushima
In-medium properties of the low-lying strange, charm, and bottom baryons in the quark-meson coupling model
14 pages, 14 eps-figures. Version accepted for Phys. Rev. D. arXiv admin note: text overlap with arXiv:1706.02688
Phys. Rev. D 99, 014026 (2019)
10.1103/PhysRevD.99.014026
LFTC-18-13/34
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In-medium properties of the low-lying strange, charm, and bottom baryons in symmetric nuclear matter are studied in the quark-meson coupling (QMC) model. Results for the Lorentz-scalar effective masses, mean field potentials felt by the light quarks in the baryons, in-medium bag radii, and the lowest mode bag eigenvalues are presented for those calculated using the updated data. This study completes the in-medium properties of the low-lying baryons in symmetric nuclear matter in the QMC model, for the strange, charm and bottom baryons which contain one or two strange, one charm or one bottom quarks, as well as at least one light quark. Highlight is the prediction of the bottom baryon Lorentz-scalar effective masses, namely, the Lorentz-scalar effective mass of $\Sigma_b$ becomes smaller than that of $\Xi_b$ at moderate nuclear matter density, $m^*_{\Sigma_b} < m^*_{\Xi_b}$, although in vacuum $m_{\Sigma_b} > m_{\Xi_b}$. We study further the effects of the repulsive Lorentz-vector potentials on the excitation (total) energies of these bottom baryons.
[ { "created": "Thu, 18 Oct 2018 22:02:39 GMT", "version": "v1" }, { "created": "Wed, 2 Jan 2019 18:48:48 GMT", "version": "v2" } ]
2019-01-23
[ [ "Tsushima", "K.", "" ] ]
In-medium properties of the low-lying strange, charm, and bottom baryons in symmetric nuclear matter are studied in the quark-meson coupling (QMC) model. Results for the Lorentz-scalar effective masses, mean field potentials felt by the light quarks in the baryons, in-medium bag radii, and the lowest mode bag eigenvalues are presented for those calculated using the updated data. This study completes the in-medium properties of the low-lying baryons in symmetric nuclear matter in the QMC model, for the strange, charm and bottom baryons which contain one or two strange, one charm or one bottom quarks, as well as at least one light quark. Highlight is the prediction of the bottom baryon Lorentz-scalar effective masses, namely, the Lorentz-scalar effective mass of $\Sigma_b$ becomes smaller than that of $\Xi_b$ at moderate nuclear matter density, $m^*_{\Sigma_b} < m^*_{\Xi_b}$, although in vacuum $m_{\Sigma_b} > m_{\Xi_b}$. We study further the effects of the repulsive Lorentz-vector potentials on the excitation (total) energies of these bottom baryons.
2102.12950
Kento Katayama
Kazuki Enomoto, Shinya Kanemura, Kento Katayama
Probing doubly charged scalar bosons from the doublet at future high-energy colliders
32 pages, 12 figures, 3 tables
Phys. Rev. D 104, 035040 (2021)
10.1103/PhysRevD.104.035040
OU-HET-1079
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The isospin doublet scalar field with hypercharge 3/2 is introduced in some new physics models such as tiny neutrino masses. Detecting the doubly charged scalar bosons from the doublet field can be a good probe of such models. However, their collider phenomenology has not been examined sufficiently. We investigate collider signatures of the doubly and singly charged scalar bosons at the LHC for the high-luminosity upgraded option (HL-LHC) by looking at transverse mass distributions etc. With the appropriate kinematical cuts we demonstrate the background reduction in the minimal model in the following two cases depending on the mass of the scalar bosons. (1) The main decay mode of the singly charged scalar bosons is the tau lepton and missing (as well as charm and strange quarks). (2) That is into a top bottom pair. In the both cases, we assume that the doubly charged scalar boson is heavier than the singly charged ones. We conclude that the scalar doublet field with $Y = 3/2$ is expected to be detectable at the HL-LHC unless the mass is too large.
[ { "created": "Thu, 25 Feb 2021 16:00:05 GMT", "version": "v1" } ]
2021-09-08
[ [ "Enomoto", "Kazuki", "" ], [ "Kanemura", "Shinya", "" ], [ "Katayama", "Kento", "" ] ]
The isospin doublet scalar field with hypercharge 3/2 is introduced in some new physics models such as tiny neutrino masses. Detecting the doubly charged scalar bosons from the doublet field can be a good probe of such models. However, their collider phenomenology has not been examined sufficiently. We investigate collider signatures of the doubly and singly charged scalar bosons at the LHC for the high-luminosity upgraded option (HL-LHC) by looking at transverse mass distributions etc. With the appropriate kinematical cuts we demonstrate the background reduction in the minimal model in the following two cases depending on the mass of the scalar bosons. (1) The main decay mode of the singly charged scalar bosons is the tau lepton and missing (as well as charm and strange quarks). (2) That is into a top bottom pair. In the both cases, we assume that the doubly charged scalar boson is heavier than the singly charged ones. We conclude that the scalar doublet field with $Y = 3/2$ is expected to be detectable at the HL-LHC unless the mass is too large.
0705.1719
Frank Tackmann
Christian W. Bauer and Frank J. Tackmann
Gaining analytic control of parton showers
12 pages, 6 figures, v2: final journal version
Phys.Rev.D76:114017,2007
10.1103/PhysRevD.76.114017
null
hep-ph
null
Parton showers are widely used to generate fully exclusive final states needed to compare theoretical models to experimental observations. While, in general, parton showers give a good description of the experimental data, the precise functional form of the probability distribution underlying the event generation is generally not known. The reason is that realistic parton showers are required to conserve four-momentum at each vertex. In this paper we investigate in detail how four-momentum conservation is enforced in a standard parton shower and why this destroys the analytic control of the probability distribution. We show how to modify a parton shower algorithm such that it conserves four-momentum at each vertex, but for which the full analytic form of the probability distribution is known. We then comment how this analytic control can be used to match matrix element calculations with parton showers, and to estimate effects of power corrections and other uncertainties in parton showers.
[ { "created": "Mon, 14 May 2007 19:50:45 GMT", "version": "v1" }, { "created": "Sat, 9 Feb 2008 03:12:17 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bauer", "Christian W.", "" ], [ "Tackmann", "Frank J.", "" ] ]
Parton showers are widely used to generate fully exclusive final states needed to compare theoretical models to experimental observations. While, in general, parton showers give a good description of the experimental data, the precise functional form of the probability distribution underlying the event generation is generally not known. The reason is that realistic parton showers are required to conserve four-momentum at each vertex. In this paper we investigate in detail how four-momentum conservation is enforced in a standard parton shower and why this destroys the analytic control of the probability distribution. We show how to modify a parton shower algorithm such that it conserves four-momentum at each vertex, but for which the full analytic form of the probability distribution is known. We then comment how this analytic control can be used to match matrix element calculations with parton showers, and to estimate effects of power corrections and other uncertainties in parton showers.
1810.12920
Debasish Borah
Debasish Borah, Dibyendu Nanda, Nimmala Narendra, Narendra Sahu
Right-handed Neutrino Dark Matter with Radiative Neutrino Mass in Gauged $B-L$ Model
32 pages, 15 figures, matches version accepted for publication in Nucl. Phys. B
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the possibility of right-handed neutrino dark matter (DM) in gauged $U(1)_{B-L} \times Z_2$ extension of the standard model augmented by an additional scalar doublet, being odd under the $Z_2$ symmetry, to give rise the scotogenic scenario of radiative neutrino masses. Due to lepton portal interactions, the right-handed neutrino DM can have additional co-annihilation channels apart from the usual annihilations through $Z_{B-L}$ which give rise to much more allowed mass of DM from relic abundance criteria, even away from the resonance region like $M_{\rm DM} \approx M_{Z_{B-L}}/2$. This enlarged parameter space is found to be consistent with neutrino mass constraints while being sensitive to direct detection experiments of DM as well as rare decay experiments looking for charged lepton flavour violating decays like $\mu \rightarrow e \gamma$. Due to the possibility of the $Z_2$ odd scalar doublet being the next to lightest stable particle that can be sufficiently produced in colliders by virtue of its gauge interactions, one can have interesting signatures like displaced vertex or disappearing charged tracks provided that the mass splitting $\delta M$ between DM and the next to lightest stable particle (NLSP) is small. In particular, if $\delta M < m_\tau=1.77$ GeV, then we get large displaced vertex signature of NLSP while being consistent with neutrino mass, lepton flavour violation and observed relic density.
[ { "created": "Tue, 30 Oct 2018 18:00:03 GMT", "version": "v1" }, { "created": "Tue, 9 Apr 2019 10:11:42 GMT", "version": "v2" }, { "created": "Thu, 7 Nov 2019 14:48:35 GMT", "version": "v3" } ]
2019-11-11
[ [ "Borah", "Debasish", "" ], [ "Nanda", "Dibyendu", "" ], [ "Narendra", "Nimmala", "" ], [ "Sahu", "Narendra", "" ] ]
We study the possibility of right-handed neutrino dark matter (DM) in gauged $U(1)_{B-L} \times Z_2$ extension of the standard model augmented by an additional scalar doublet, being odd under the $Z_2$ symmetry, to give rise the scotogenic scenario of radiative neutrino masses. Due to lepton portal interactions, the right-handed neutrino DM can have additional co-annihilation channels apart from the usual annihilations through $Z_{B-L}$ which give rise to much more allowed mass of DM from relic abundance criteria, even away from the resonance region like $M_{\rm DM} \approx M_{Z_{B-L}}/2$. This enlarged parameter space is found to be consistent with neutrino mass constraints while being sensitive to direct detection experiments of DM as well as rare decay experiments looking for charged lepton flavour violating decays like $\mu \rightarrow e \gamma$. Due to the possibility of the $Z_2$ odd scalar doublet being the next to lightest stable particle that can be sufficiently produced in colliders by virtue of its gauge interactions, one can have interesting signatures like displaced vertex or disappearing charged tracks provided that the mass splitting $\delta M$ between DM and the next to lightest stable particle (NLSP) is small. In particular, if $\delta M < m_\tau=1.77$ GeV, then we get large displaced vertex signature of NLSP while being consistent with neutrino mass, lepton flavour violation and observed relic density.
0905.3058
Irais Bautista
I. Bautista, L. Cunqueiro, J. Dias de Deus and C. Pajares
Particle production azimuthal asymmetries in a clustering of color sources model
To appear in Journal of Physics G
J.Phys.G37:015103,2010
10.1088/0954-3899/37/1/015103
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The collective interactions of many partons in the first stage of the collisions is the usual accepted explanation of the sizable elliptical flow. The clustering of color sources provides a framework of partonic interactions. In this scheme, we show a reasonable agreement with RHIC data for pT<1.5 GeV/c in both the dependence of v2 transverse momentum and in the shape of the nuclear modified factor on the azimuthal angle for different centralities. We show the predictions at LHC energies for Pb-Pb. In the case of proton-proton collisions a sizable v2 is obtained at this energy.
[ { "created": "Tue, 19 May 2009 16:18:42 GMT", "version": "v1" }, { "created": "Wed, 20 May 2009 14:51:17 GMT", "version": "v2" }, { "created": "Thu, 15 Oct 2009 18:30:08 GMT", "version": "v3" } ]
2014-11-18
[ [ "Bautista", "I.", "" ], [ "Cunqueiro", "L.", "" ], [ "de Deus", "J. Dias", "" ], [ "Pajares", "C.", "" ] ]
The collective interactions of many partons in the first stage of the collisions is the usual accepted explanation of the sizable elliptical flow. The clustering of color sources provides a framework of partonic interactions. In this scheme, we show a reasonable agreement with RHIC data for pT<1.5 GeV/c in both the dependence of v2 transverse momentum and in the shape of the nuclear modified factor on the azimuthal angle for different centralities. We show the predictions at LHC energies for Pb-Pb. In the case of proton-proton collisions a sizable v2 is obtained at this energy.
1911.06345
Nikolai Zerf
Nikolai Zerf
Fermion Traces Without Evanescence
33 pages, 3 figures, v2 journal version
Phys. Rev. D 101, 036002 (2020)
10.1103/PhysRevD.101.036002
HU-EP-19/35
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We outline the evaluation of $n$-dimensional fermion traces ($n\in\mathbb{N}$) built by products of Dirac-$\gamma$ matrices suitable for a uniform dimensional continuation. Such a continuation is needed for calculations employing a dimensional regulator whenever intrinsically integer dimensional tensors yield non-vanishing contributions. A prime example for such a tensor is given by $\gamma_5$ for $n=4$. The main difference between Dimensional Regularization (DREG) and a Dimensionally Continued Regularization (DCREG) is that DCREG does not attempt to lift the algebra to continuous $d$ dimensions ($d\in\mathbb{R}$). As a consequence one has to properly deal with evanescent structures in order to ensure the uniform application of the regulator. In basic steps we identify evanescent structures in fermion traces and show that their proper treatment is crucial for example when calculating the $VVA$ anomaly in four dimensions. We checked that the performed considerations enable the evaluation of Standard Model (SM) $Z$-factors within DCREG up to including three loops.
[ { "created": "Thu, 14 Nov 2019 19:02:49 GMT", "version": "v1" }, { "created": "Tue, 11 Feb 2020 10:41:55 GMT", "version": "v2" } ]
2020-02-12
[ [ "Zerf", "Nikolai", "" ] ]
We outline the evaluation of $n$-dimensional fermion traces ($n\in\mathbb{N}$) built by products of Dirac-$\gamma$ matrices suitable for a uniform dimensional continuation. Such a continuation is needed for calculations employing a dimensional regulator whenever intrinsically integer dimensional tensors yield non-vanishing contributions. A prime example for such a tensor is given by $\gamma_5$ for $n=4$. The main difference between Dimensional Regularization (DREG) and a Dimensionally Continued Regularization (DCREG) is that DCREG does not attempt to lift the algebra to continuous $d$ dimensions ($d\in\mathbb{R}$). As a consequence one has to properly deal with evanescent structures in order to ensure the uniform application of the regulator. In basic steps we identify evanescent structures in fermion traces and show that their proper treatment is crucial for example when calculating the $VVA$ anomaly in four dimensions. We checked that the performed considerations enable the evaluation of Standard Model (SM) $Z$-factors within DCREG up to including three loops.
1910.09656
Benjamin Guiot
Benjamin Guiot
Pathologies of the KMR prescriptions for unintegrated PDFs: Which prescription should be preferred?
Journal version. Published in Phys. Rev. D. 19 pages, 7 figures
Phys. Rev. D 101, 054006 (2020)
10.1103/PhysRevD.101.054006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the different Kimber-Martin-Ryskin (KMR) prescriptions for unintegrated parton distribution functions (uPDFs). We show that the strong-ordering (SO) and the angular-ordering (AO) cut-offs lead to strong discrepancies between the obtained cross sections. While the result obtained with the AO cut-off overestimates the heavy-flavor cross section by about a factor 3, the SO cut-off gives the correct answer. We also solve the issue of the KMR uPDFs definitions mentioned by Golec-Biernat and Sta\'sto, and show that, in the case of the AO cut-off, the KMR uPDFs are ill-defined.
[ { "created": "Mon, 21 Oct 2019 21:04:42 GMT", "version": "v1" }, { "created": "Thu, 5 Mar 2020 18:46:18 GMT", "version": "v2" } ]
2020-03-11
[ [ "Guiot", "Benjamin", "" ] ]
We discuss the different Kimber-Martin-Ryskin (KMR) prescriptions for unintegrated parton distribution functions (uPDFs). We show that the strong-ordering (SO) and the angular-ordering (AO) cut-offs lead to strong discrepancies between the obtained cross sections. While the result obtained with the AO cut-off overestimates the heavy-flavor cross section by about a factor 3, the SO cut-off gives the correct answer. We also solve the issue of the KMR uPDFs definitions mentioned by Golec-Biernat and Sta\'sto, and show that, in the case of the AO cut-off, the KMR uPDFs are ill-defined.
1510.04200
Philippe Rosnet
P. Rosnet
Quark-Gluon Plasma: from accelerator experiments to early Universe
8 pages, 5 figures, writeup of a talk given at the Rencontres du Vietnam 2015 on Cosmology
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the Big Bang scenario, the early Universe is characterized by the {\it particle era}, i.e. a Universe made of particles. This period connects both scales of fundamental physics: infinitesimally small and infinitely large. So, particle physics and in particular experimental programs at accelerators can bring valuable inputs for the understanding of the early Universe and its evolution. These proceedings discuss the impact of the Quantum ChromoDynamics phase transition experienced by the {\it particle era} in the expanding Universe, which is connected to the study of the Quark-Gluon Plasma produced in heavy-ion physics experiments.
[ { "created": "Wed, 14 Oct 2015 17:04:55 GMT", "version": "v1" } ]
2015-10-15
[ [ "Rosnet", "P.", "" ] ]
In the Big Bang scenario, the early Universe is characterized by the {\it particle era}, i.e. a Universe made of particles. This period connects both scales of fundamental physics: infinitesimally small and infinitely large. So, particle physics and in particular experimental programs at accelerators can bring valuable inputs for the understanding of the early Universe and its evolution. These proceedings discuss the impact of the Quantum ChromoDynamics phase transition experienced by the {\it particle era} in the expanding Universe, which is connected to the study of the Quark-Gluon Plasma produced in heavy-ion physics experiments.
1802.00456
Andrea Isgr\`o
Radja Boughezal, Andrea Isgr\`o, Frank Petriello
Next-to-leading-logarithmic power corrections for $N$-jettiness subtraction in color-singlet production
30 pages, 12 figures. Improved plots and added clarifications as well as minor corrections
Phys. Rev. D 97, 076006 (2018)
10.1103/PhysRevD.97.076006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a detailed derivation of the power corrections to the factorization theorem for the 0-jettiness event shape variable $\mathcal{T}$. Our calculation is performed directly in QCD without using the formalism of effective field theory. We analytically calculate the next-to-leading logarithmic power corrections for small $\mathcal{T}$ at next-to-leading order in the strong coupling constant, extending previous computations which obtained only the leading-logarithmic power corrections. We address a discrepancy in the literature between results for the leading-logarithmic power corrections to a particular definition of 0-jettiness. We present a numerical study of the power corrections in the context of their application to the $N$-jettiness subtraction method for higher-order calculations, using gluon-fusion Higgs production as an example. The inclusion of the next-to-leading-logarithmic power corrections further improves the numerical efficiency of the approach beyond the improvement obtained from the leading-logarithmic power corrections.
[ { "created": "Thu, 1 Feb 2018 19:00:46 GMT", "version": "v1" }, { "created": "Mon, 27 Aug 2018 18:52:56 GMT", "version": "v2" } ]
2018-08-29
[ [ "Boughezal", "Radja", "" ], [ "Isgrò", "Andrea", "" ], [ "Petriello", "Frank", "" ] ]
We present a detailed derivation of the power corrections to the factorization theorem for the 0-jettiness event shape variable $\mathcal{T}$. Our calculation is performed directly in QCD without using the formalism of effective field theory. We analytically calculate the next-to-leading logarithmic power corrections for small $\mathcal{T}$ at next-to-leading order in the strong coupling constant, extending previous computations which obtained only the leading-logarithmic power corrections. We address a discrepancy in the literature between results for the leading-logarithmic power corrections to a particular definition of 0-jettiness. We present a numerical study of the power corrections in the context of their application to the $N$-jettiness subtraction method for higher-order calculations, using gluon-fusion Higgs production as an example. The inclusion of the next-to-leading-logarithmic power corrections further improves the numerical efficiency of the approach beyond the improvement obtained from the leading-logarithmic power corrections.
hep-ph/0401181
Mustafa Savci
T. M. Aliev, A. Ozpineci, M. Savci
Semileptonic (D_s^+ -> phi l nu) decay in QCD light cone sum rule
11 pages
null
null
metu-phys-hep-04-06
hep-ph
null
We calculate the form factors V, A_1, A_2 and A_0 appearing in the (D -> phi) transition in light cone QCD sum rule method. We compare our results on these form factors with the current experimental results and existing theoretical calculations.
[ { "created": "Fri, 23 Jan 2004 14:27:56 GMT", "version": "v1" } ]
2007-05-23
[ [ "Aliev", "T. M.", "" ], [ "Ozpineci", "A.", "" ], [ "Savci", "M.", "" ] ]
We calculate the form factors V, A_1, A_2 and A_0 appearing in the (D -> phi) transition in light cone QCD sum rule method. We compare our results on these form factors with the current experimental results and existing theoretical calculations.
1101.5394
Jeppe R. Andersen
Jeppe R. Andersen and Jennifer M. Smillie
Multiple Jets at the LHC with High Energy Jets
null
JHEP 1106:010,2011
10.1007/JHEP06(2011)010
CP3-Origins-2011-02, Edinburgh 2011/03
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a flexible Monte Carlo implementation of the perturbative framework of High Energy Jets, describing multi-jet events at hadron colliders. The description includes a resummation which ensures leading logarithmic accuracy for large invariant mass between jets, and is matched to tree-level accuracy for multiplicities up to 4 jets. The resummation includes all-order hard corrections, which become important for increasing centre-of-mass energy of the hadronic collision. We discuss observables relevant for confronting the perturbative framework with 7 TeV data from the LHC, and the impact of the perturbative corrections on several dijet and trijet observables which are relevant in the search for new physics.
[ { "created": "Thu, 27 Jan 2011 21:05:12 GMT", "version": "v1" } ]
2015-03-18
[ [ "Andersen", "Jeppe R.", "" ], [ "Smillie", "Jennifer M.", "" ] ]
We present a flexible Monte Carlo implementation of the perturbative framework of High Energy Jets, describing multi-jet events at hadron colliders. The description includes a resummation which ensures leading logarithmic accuracy for large invariant mass between jets, and is matched to tree-level accuracy for multiplicities up to 4 jets. The resummation includes all-order hard corrections, which become important for increasing centre-of-mass energy of the hadronic collision. We discuss observables relevant for confronting the perturbative framework with 7 TeV data from the LHC, and the impact of the perturbative corrections on several dijet and trijet observables which are relevant in the search for new physics.
hep-ph/0004174
Stephane Munier
S. Munier (SPhT, CEA/Saclay)
Forward jets in the colour-dipole model
null
Phys.Rev. D63 (2001) 034015
10.1103/PhysRevD.63.034015
Saclay T00/058
hep-ph
null
We show that a forward jet with large transverse momentum in an onium-onium collision is a hard probe which can be effectively characterized by a colour- dipole distribution at the time of the interaction. The dipole distribution is computed, and compared to its counterpart for a virtual photon in the initial state. We find that while in the photon case, the tail of large sizes is exponentially cut-off, it contributes sizeably in the forward-jet case, which signs the sensitivity of observables based on such events to the infrared region. Moreover, a direct probabilistic interpretation of the dipole distribution fails since it takes negative values in the large size region.
[ { "created": "Tue, 18 Apr 2000 13:29:38 GMT", "version": "v1" } ]
2009-10-31
[ [ "Munier", "S.", "", "SPhT, CEA/Saclay" ] ]
We show that a forward jet with large transverse momentum in an onium-onium collision is a hard probe which can be effectively characterized by a colour- dipole distribution at the time of the interaction. The dipole distribution is computed, and compared to its counterpart for a virtual photon in the initial state. We find that while in the photon case, the tail of large sizes is exponentially cut-off, it contributes sizeably in the forward-jet case, which signs the sensitivity of observables based on such events to the infrared region. Moreover, a direct probabilistic interpretation of the dipole distribution fails since it takes negative values in the large size region.
0910.5544
Eray Sabancilar
Eray Sabancilar
Cosmological Constraints on Strongly Coupled Moduli from Cosmic Strings
14 pages, 2 figures
Phys.Rev.D81:123502,2010
10.1103/PhysRevD.81.123502
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cosmological constraints on moduli, whose coupling to matter is stronger than Planck mass suppressed coupling, are derived. In particular, moduli are considered to be produced by oscillating loops of cosmic strings and constraints are obtained from their effects on big bang nucleosynthesis and their contribution to diffuse gamma ray background and dark matter. Large volume and warped Type-IIB flux compactifications are taken as examples where strongly coupled moduli are present. Finally, the constraints on cosmic string tension, modulus mass and modulus coupling constant are obtained and it is shown that the constraints are relaxed significantly when the coupling constant is large enough. In addition, the effects of thermal production of moduli are considered and the corresponding constraints are derived.
[ { "created": "Thu, 29 Oct 2009 03:41:39 GMT", "version": "v1" } ]
2010-11-08
[ [ "Sabancilar", "Eray", "" ] ]
Cosmological constraints on moduli, whose coupling to matter is stronger than Planck mass suppressed coupling, are derived. In particular, moduli are considered to be produced by oscillating loops of cosmic strings and constraints are obtained from their effects on big bang nucleosynthesis and their contribution to diffuse gamma ray background and dark matter. Large volume and warped Type-IIB flux compactifications are taken as examples where strongly coupled moduli are present. Finally, the constraints on cosmic string tension, modulus mass and modulus coupling constant are obtained and it is shown that the constraints are relaxed significantly when the coupling constant is large enough. In addition, the effects of thermal production of moduli are considered and the corresponding constraints are derived.
0908.2531
Michael Klasen
M. Klasen (LPSC Grenoble), G. Kramer (Univ. Hamburg)
Survival probability for diffractive dijet production in p-pbar collisions from next-to-leading order calculations
26 pages, 11 figures
Phys.Rev.D80:074006,2009
10.1103/PhysRevD.80.074006
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform next-to-leading order calculations of the single-diffractive and non-diffractive cross sections for dijet production in proton-antiproton collisions at the Tevatron. By comparing their ratio to the data published by the CDF collaboration for two different center-of-mass energies, we deduce the rapidity-gap survival probability as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in proton-antiproton collisions depends on the momentum fraction of the parton in the Pomeron even at next-to-leading order.
[ { "created": "Tue, 18 Aug 2009 09:51:02 GMT", "version": "v1" } ]
2009-11-06
[ [ "Klasen", "M.", "", "LPSC Grenoble" ], [ "Kramer", "G.", "", "Univ. Hamburg" ] ]
We perform next-to-leading order calculations of the single-diffractive and non-diffractive cross sections for dijet production in proton-antiproton collisions at the Tevatron. By comparing their ratio to the data published by the CDF collaboration for two different center-of-mass energies, we deduce the rapidity-gap survival probability as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in proton-antiproton collisions depends on the momentum fraction of the parton in the Pomeron even at next-to-leading order.
hep-ph/0207202
Xing ZhiZhong
Zhi-zhong Xing
Determining Strong and Weak Phases in B_d -> D^{(*)\pm} D^{(*)\mp} Decays
LaTex 4 pages with style file. Talk given at the XIVth Rencontres de Blois on Matter-Antimatter Asymmetry, 16 - 22 June 2002, Blois, France
High Energy Phys.Nucl.Phys. 26 (2002) 100-103
null
null
hep-ph
null
We show that both the weak phase \beta and the strong phase \delta_d can be determined from the time-dependent measurement of B_d -> D^{*\pm} D^{\mp} decays, whose final states are non-CP eigenstates. It is also possible to extract \beta from B_d -> D^{*\pm} D^{*\mp} transitions without doing the angular analysis. Possible final-state rescattering effects in B_d -> D^{(*)\pm} D^{(*)\mp} channels are discussed by means of the isospin analysis. We emphasize that it is worthwhile to check whether the naive factorization approximation works or not for such B-meson decay modes into two heavy charmed mesons.
[ { "created": "Wed, 17 Jul 2002 09:49:44 GMT", "version": "v1" } ]
2007-05-23
[ [ "Xing", "Zhi-zhong", "" ] ]
We show that both the weak phase \beta and the strong phase \delta_d can be determined from the time-dependent measurement of B_d -> D^{*\pm} D^{\mp} decays, whose final states are non-CP eigenstates. It is also possible to extract \beta from B_d -> D^{*\pm} D^{*\mp} transitions without doing the angular analysis. Possible final-state rescattering effects in B_d -> D^{(*)\pm} D^{(*)\mp} channels are discussed by means of the isospin analysis. We emphasize that it is worthwhile to check whether the naive factorization approximation works or not for such B-meson decay modes into two heavy charmed mesons.
hep-ph/0702073
Grzegorz Wilk
Oleg Utyuzh, Grzegorz Wilk and Zbigniew Wlodarczyk
Modelling Bose Einstein Correlations via Elementary Emitting Cells
18 pages, 16 figures, 3 tables. Final version, to appear in Phys. Rev. D
Phys.Rev.D75:074030,2007
10.1103/PhysRevD.75.074030
null
hep-ph nucl-th
null
We propose a method of numerical modeling Bose Einstein Correlations by using the notion of Elementary Emitting Cells (EEC). They are intermediary objects containing identical bosons and are supposed to be produced independently during the hadronization process. Only bosons in EEC, which represents a single quantum state here, are subjected to the effects of Bose-Einstein (BE) statistics, which forces them to follow a geometrical distribution. There are no such effects between particles from different EECs. We illustrate our proposition by calculating a representative number of typical distributions and discussing their sensitivity to EECs and their characteristics.
[ { "created": "Wed, 7 Feb 2007 15:15:09 GMT", "version": "v1" }, { "created": "Tue, 3 Apr 2007 12:00:11 GMT", "version": "v2" }, { "created": "Tue, 24 Apr 2007 09:24:41 GMT", "version": "v3" } ]
2008-11-26
[ [ "Utyuzh", "Oleg", "" ], [ "Wilk", "Grzegorz", "" ], [ "Wlodarczyk", "Zbigniew", "" ] ]
We propose a method of numerical modeling Bose Einstein Correlations by using the notion of Elementary Emitting Cells (EEC). They are intermediary objects containing identical bosons and are supposed to be produced independently during the hadronization process. Only bosons in EEC, which represents a single quantum state here, are subjected to the effects of Bose-Einstein (BE) statistics, which forces them to follow a geometrical distribution. There are no such effects between particles from different EECs. We illustrate our proposition by calculating a representative number of typical distributions and discussing their sensitivity to EECs and their characteristics.
2111.13079
Yushi Mura
Kazuki Enomoto, Shinya Kanemura and Yushi Mura
Electroweak baryogenesis in aligned two Higgs doublet models
35 pages, 5 figures, 1 table
null
10.1007/JHEP01(2022)104
OU-HET-1114
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate the baryon number abundance based on the charge transport scenario of top quarks in the CP-violating two Higgs doublet model, in which Yukawa interactions are aligned to avoid dangerous flavor changing neutral currents, and coupling constants of the lightest Higgs boson with the mass $125~\mathrm{GeV}$ coincide with those in the standard model at tree level to satisfy the current LHC data. In this model, the severe constraint from the electric dipole moment of electrons, which are normally difficult to be satisfied, can be avoided by destructive interferences between CP-violating phases in Yukawa interactions and scalar couplings in the Higgs potential. Viable benchmark scenarios are proposed under the current available data and basic theoretical bounds. We find that the observed baryon number can be reproduced in this model, where masses of additional Higgs bosons are typically $300$--$400~\mathrm{GeV}$. Furthermore, it is found that the triple Higgs boson coupling is predicted to be $35$--$55~\%$ larger than the standard model value.
[ { "created": "Thu, 25 Nov 2021 13:35:01 GMT", "version": "v1" } ]
2022-01-25
[ [ "Enomoto", "Kazuki", "" ], [ "Kanemura", "Shinya", "" ], [ "Mura", "Yushi", "" ] ]
We evaluate the baryon number abundance based on the charge transport scenario of top quarks in the CP-violating two Higgs doublet model, in which Yukawa interactions are aligned to avoid dangerous flavor changing neutral currents, and coupling constants of the lightest Higgs boson with the mass $125~\mathrm{GeV}$ coincide with those in the standard model at tree level to satisfy the current LHC data. In this model, the severe constraint from the electric dipole moment of electrons, which are normally difficult to be satisfied, can be avoided by destructive interferences between CP-violating phases in Yukawa interactions and scalar couplings in the Higgs potential. Viable benchmark scenarios are proposed under the current available data and basic theoretical bounds. We find that the observed baryon number can be reproduced in this model, where masses of additional Higgs bosons are typically $300$--$400~\mathrm{GeV}$. Furthermore, it is found that the triple Higgs boson coupling is predicted to be $35$--$55~\%$ larger than the standard model value.
1903.03380
Takaaki Nomura
Chuan-Hung Chen, Takaaki Nomura
Influence of an inert charged Higgs boson on the muon $g-2$ and radiative neutrino masses in a scotogenic model
26 pages, 10 figures, version published in PRD
Phys. Rev. D 100, 015024 (2019)
10.1103/PhysRevD.100.015024
KIAS-P19014
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A simple extension of Ma's approach in a scotogenic model is studied for the purpose of simultaneously interpreting the neutrino data and the excess of muon anomalous magnetic moment (muon $g-2$). The feasible minimal extension is to add an $Z_2$-odd vector-like lepton doublet to the Ma's model. It is found that in addition to the neutrino data, the strict constraints on the relevant parameters are from the electroweak oblique parameters and the induced lepton-flavor violation processes, such as $\ell_i \to \ell_j \gamma$ and $\ell_i \to \ell^-_j \ell^-_j \ell^+_j$. Performing parameter scan, we numerically demonstrate that when the constraint conditions are satisfied, the muon $g-2$ of $O(10^{-9})$ can be achieved, where it can be expected that with a $5\sigma$ observation, the Muon $g-2$ experiment at Fermilab can observe $a_\mu \approx 13.31 \times 10^{-10}$ when the current experiment and the SM errors are reduced by a factor of 4 and 2, respectively. Moreover, the branching ratio of the $\tau \to \mu \gamma$ decay can match the Belle II sensitivity of $O(10^{-9})$ with an integrated luminosity of 50 ab$^{-1}$.
[ { "created": "Fri, 8 Mar 2019 11:45:10 GMT", "version": "v1" }, { "created": "Tue, 19 Mar 2019 13:36:33 GMT", "version": "v2" }, { "created": "Thu, 18 Jul 2019 08:37:37 GMT", "version": "v3" } ]
2019-07-24
[ [ "Chen", "Chuan-Hung", "" ], [ "Nomura", "Takaaki", "" ] ]
A simple extension of Ma's approach in a scotogenic model is studied for the purpose of simultaneously interpreting the neutrino data and the excess of muon anomalous magnetic moment (muon $g-2$). The feasible minimal extension is to add an $Z_2$-odd vector-like lepton doublet to the Ma's model. It is found that in addition to the neutrino data, the strict constraints on the relevant parameters are from the electroweak oblique parameters and the induced lepton-flavor violation processes, such as $\ell_i \to \ell_j \gamma$ and $\ell_i \to \ell^-_j \ell^-_j \ell^+_j$. Performing parameter scan, we numerically demonstrate that when the constraint conditions are satisfied, the muon $g-2$ of $O(10^{-9})$ can be achieved, where it can be expected that with a $5\sigma$ observation, the Muon $g-2$ experiment at Fermilab can observe $a_\mu \approx 13.31 \times 10^{-10}$ when the current experiment and the SM errors are reduced by a factor of 4 and 2, respectively. Moreover, the branching ratio of the $\tau \to \mu \gamma$ decay can match the Belle II sensitivity of $O(10^{-9})$ with an integrated luminosity of 50 ab$^{-1}$.
1312.7120
Kirill Semenov-Tian-Shansky
B.Pire, K.Semenov-Tian-Shansky, L.Szymanowski
Nucleon-to-pion transition distribution amplitudes: a challenge for PANDA
6 pages, 4 figures. Contribution presented at the Lightcone 2013+ Conference, Skiathos, Greece, 20-24 May, 2013. To be published in Few Body Systems
null
10.1007/s00601-013-0774-2
CPHT-PC094.1013
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Baryon-to-meson Transition Distribution Amplitudes (TDAs) appear as building blocks in the collinear factorized description of amplitudes for a class of hard exclusive reactions, prominent examples being hard exclusive pion electroproduction off a nucleon in the backward region and baryon-antibaryon annihilation into a pion and a lepton pair or a charmonium. Baryon-to-meson TDAs extend both the concepts of generalized parton distributions (GPDs) and baryon distribution amplitudes (DAs) encoding valuable complementary information on the hadronic structure. We review the basic properties of baryon-to-meson TDAs and discuss the perspectives for the experimental access with the PANDA detector.
[ { "created": "Thu, 26 Dec 2013 15:20:57 GMT", "version": "v1" } ]
2013-12-30
[ [ "Pire", "B.", "" ], [ "Semenov-Tian-Shansky", "K.", "" ], [ "Szymanowski", "L.", "" ] ]
Baryon-to-meson Transition Distribution Amplitudes (TDAs) appear as building blocks in the collinear factorized description of amplitudes for a class of hard exclusive reactions, prominent examples being hard exclusive pion electroproduction off a nucleon in the backward region and baryon-antibaryon annihilation into a pion and a lepton pair or a charmonium. Baryon-to-meson TDAs extend both the concepts of generalized parton distributions (GPDs) and baryon distribution amplitudes (DAs) encoding valuable complementary information on the hadronic structure. We review the basic properties of baryon-to-meson TDAs and discuss the perspectives for the experimental access with the PANDA detector.
1906.10145
Julian Heeck
Raghuveer Garani, Julian Heeck
Dark matter interactions with muons in neutron stars
7 pages; v2: added references and improved heating from annihilations; v3: matches PRD version
Phys. Rev. D 100, 035039 (2019)
10.1103/PhysRevD.100.035039
ULB-TH/19-05, UCI-TR-2019-17
hep-ph astro-ph.CO astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neutron stars contain a significant number of stable muons due to the large chemical potential and degenerate electrons. This makes them the unique vessel to capture muonphilic dark matter, which does not interact with other astrophysical objects, including Earth and its direct-detection experiments. The infalling dark matter can heat up the neutron star both kinetically and via annihilations, which is potentially observable with future infrared telescopes. New physics models for muonphilic dark matter can easily be motivated by, and connected to, existing anomalies in the muon sector, e.g., the anomalous magnetic moment or LHCb's recent hints for lepton-flavor non-universality in $B\to K\mu^+\mu^-$ decays. We study the implications for a model with dark matter charged under a local $U(1)_{L_\mu-L_\tau}$.
[ { "created": "Mon, 24 Jun 2019 18:00:07 GMT", "version": "v1" }, { "created": "Tue, 2 Jul 2019 17:46:13 GMT", "version": "v2" }, { "created": "Tue, 27 Aug 2019 20:39:52 GMT", "version": "v3" } ]
2019-09-04
[ [ "Garani", "Raghuveer", "" ], [ "Heeck", "Julian", "" ] ]
Neutron stars contain a significant number of stable muons due to the large chemical potential and degenerate electrons. This makes them the unique vessel to capture muonphilic dark matter, which does not interact with other astrophysical objects, including Earth and its direct-detection experiments. The infalling dark matter can heat up the neutron star both kinetically and via annihilations, which is potentially observable with future infrared telescopes. New physics models for muonphilic dark matter can easily be motivated by, and connected to, existing anomalies in the muon sector, e.g., the anomalous magnetic moment or LHCb's recent hints for lepton-flavor non-universality in $B\to K\mu^+\mu^-$ decays. We study the implications for a model with dark matter charged under a local $U(1)_{L_\mu-L_\tau}$.
hep-ph/0106151
Johann Rafelski
Jean Letessier (Paris) and Johann Rafelski (Tucson)
Rapidity particle spectra in sudden hadronization of QGP
3 pages including 2 figures
J.Phys.G28:183-188,2002
10.1088/0954-3899/28/1/313
null
hep-ph
null
We show that the remaining internal longitudinal flow of colliding quarks in nuclei offers a natural explanation for the diversity of rapidity spectral shapes observed in Pb--Pb 158AGeV nuclear collisions. Thus QGP sudden hadronization reaction picture is a suitable approach to explain the rapidity spectra of hadrons produced.
[ { "created": "Thu, 14 Jun 2001 14:47:07 GMT", "version": "v1" } ]
2008-11-26
[ [ "Letessier", "Jean", "", "Paris" ], [ "Rafelski", "Johann", "", "Tucson" ] ]
We show that the remaining internal longitudinal flow of colliding quarks in nuclei offers a natural explanation for the diversity of rapidity spectral shapes observed in Pb--Pb 158AGeV nuclear collisions. Thus QGP sudden hadronization reaction picture is a suitable approach to explain the rapidity spectra of hadrons produced.
hep-ph/0407069
Gabriele Bodenmueller
Harald Fritzsch
The Physics of Flavor - Challenge for the Future
7 pages, Korea Meeting ICFP03
J.Korean Phys.Soc. 45 (2004) S297-S300
null
LMU 27 / 03
hep-ph
null
This is the summary talk for the theoretical part of ICFP03. The contents of the talk are reviewed and a general outlook is given.
[ { "created": "Tue, 6 Jul 2004 13:50:40 GMT", "version": "v1" } ]
2007-05-23
[ [ "Fritzsch", "Harald", "" ] ]
This is the summary talk for the theoretical part of ICFP03. The contents of the talk are reviewed and a general outlook is given.
0709.1862
Jonathan Roberts
D. Jarecka, J. Kalinowski, S.F. King and J.P. Roberts
Dark Matter in the U(1) Extended SUSY
4 pages, 2 figures. Presented by J. Kalinowski at the International Linear Collider Workshop 2007: LCWS2007 and ILC2007, DESY, Hamburg
ECONF C0705302:SUS15,2007
null
null
hep-ph
null
The neutralino sector of the U(1) extended SUSY is presented and some collider and cosmology-related phenomenology discussed.
[ { "created": "Wed, 12 Sep 2007 13:28:40 GMT", "version": "v1" } ]
2009-02-16
[ [ "Jarecka", "D.", "" ], [ "Kalinowski", "J.", "" ], [ "King", "S. F.", "" ], [ "Roberts", "J. P.", "" ] ]
The neutralino sector of the U(1) extended SUSY is presented and some collider and cosmology-related phenomenology discussed.
hep-ph/9503210
Takeo Moroi
Takeo Moroi
Effects of the Gravitino on the Inflationary Universe
Ph.D thesis, 125 pages.
null
null
TU-479
hep-ph
null
Gravitino problem is discussed in detail. We derive an upperbound on the reheating temperature from the constraints of the big-bang nucleosynthesis and the present mass density of the universe. Compared to previous works, we have improve the following three points; (i) the gravitino production cross sections are calculated by taking all the relevant terms in the supergravity lagrangian into account, (ii) high energy photon spectrum is obtained by solving the Boltzmann equations numerically, and (iii) the evolutions of the light elements (D, T, $^3$He, $^4$He) at the temperature lower than $\sim$1MeV are calculated by using modified Kawano's computer code.
[ { "created": "Thu, 2 Mar 1995 10:24:33 GMT", "version": "v1" } ]
2016-09-01
[ [ "Moroi", "Takeo", "" ] ]
Gravitino problem is discussed in detail. We derive an upperbound on the reheating temperature from the constraints of the big-bang nucleosynthesis and the present mass density of the universe. Compared to previous works, we have improve the following three points; (i) the gravitino production cross sections are calculated by taking all the relevant terms in the supergravity lagrangian into account, (ii) high energy photon spectrum is obtained by solving the Boltzmann equations numerically, and (iii) the evolutions of the light elements (D, T, $^3$He, $^4$He) at the temperature lower than $\sim$1MeV are calculated by using modified Kawano's computer code.
1609.07692
Hong-Shi Zong
Wei Wei, Hai-Xiao Xiao, and Hong-Shi Zong
Chiral phase transition in QED$_3$ at finite temperature
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Chiral phase transition in (2+1)-dimensional quantum electrodynamics (QED$_3$) at finite temperature is investigated in the framework of truncated Dyson-Schwinger equations (DSEs). We go beyond the widely used instantaneous approximation and adopt a method that retains the full frequency dependence of the fermion self-energy. We also take further step to include the effects of wave-function renormalizations and introduce a minimal dressing of the bare vertex. Finally, with the more complete solutions of the truncated DSEs, we revisit the study of chiral phase transition in finite-temperature QED$_3$.
[ { "created": "Sun, 25 Sep 2016 02:42:34 GMT", "version": "v1" } ]
2016-09-27
[ [ "Wei", "Wei", "" ], [ "Xiao", "Hai-Xiao", "" ], [ "Zong", "Hong-Shi", "" ] ]
Chiral phase transition in (2+1)-dimensional quantum electrodynamics (QED$_3$) at finite temperature is investigated in the framework of truncated Dyson-Schwinger equations (DSEs). We go beyond the widely used instantaneous approximation and adopt a method that retains the full frequency dependence of the fermion self-energy. We also take further step to include the effects of wave-function renormalizations and introduce a minimal dressing of the bare vertex. Finally, with the more complete solutions of the truncated DSEs, we revisit the study of chiral phase transition in finite-temperature QED$_3$.
2308.05642
Gurucharan Mohanta
Gurucharan Mohanta, Ketan M. Patel
Gauged $SU(3)_F$ and loop induced quark and lepton masses
v1: 25 pages, 5 tables, 1 figure; v2: minor changes, references added, published version
JHEP 10 (2023) 128
10.1007/JHEP10(2023)128
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We investigate a local $SU(3)_F$ flavour symmetry for its viability in generating the masses for the quarks and charged leptons of the first two families through radiative corrections. Only the third-generation fermions get tree-level masses due to specific choice of the field content and their gauge charges. Unprotected by symmetry, the remaining fermions acquire non-vanishing masses through the quantum corrections induced by the gauge bosons of broken $SU(3)_F$. We show that inter-generational hierarchy between the masses of the first two families arises if the flavour symmetry is broken with an intermediate $SU(2)$ leading to a specific ordering in the masses of the gauge bosons. Based on this scheme, we construct an explicit and predictive model and show its viability in reproducing the realistic charged fermion masses and quark mixing parameters in terms of not-so-hierarchical fundamental couplings. The model leads to the strange quark mass, $m_s \approx 16$ MeV at $M_Z$, which is $\sim 2.4 \sigma$ away from its current central value. Large flavour violations are a generic prediction of the scheme which pushes the masses of the new gauge bosons to $10^3$ TeV or higher.
[ { "created": "Thu, 10 Aug 2023 15:35:33 GMT", "version": "v1" }, { "created": "Mon, 23 Oct 2023 11:21:00 GMT", "version": "v2" } ]
2023-10-24
[ [ "Mohanta", "Gurucharan", "" ], [ "Patel", "Ketan M.", "" ] ]
We investigate a local $SU(3)_F$ flavour symmetry for its viability in generating the masses for the quarks and charged leptons of the first two families through radiative corrections. Only the third-generation fermions get tree-level masses due to specific choice of the field content and their gauge charges. Unprotected by symmetry, the remaining fermions acquire non-vanishing masses through the quantum corrections induced by the gauge bosons of broken $SU(3)_F$. We show that inter-generational hierarchy between the masses of the first two families arises if the flavour symmetry is broken with an intermediate $SU(2)$ leading to a specific ordering in the masses of the gauge bosons. Based on this scheme, we construct an explicit and predictive model and show its viability in reproducing the realistic charged fermion masses and quark mixing parameters in terms of not-so-hierarchical fundamental couplings. The model leads to the strange quark mass, $m_s \approx 16$ MeV at $M_Z$, which is $\sim 2.4 \sigma$ away from its current central value. Large flavour violations are a generic prediction of the scheme which pushes the masses of the new gauge bosons to $10^3$ TeV or higher.
1312.0664
Juan Jose Sanz-Cillero
Juan Jose Sanz-Cillero, De-Liang Yao and Han-Qing Zheng
Positivity constraints on the low-energy constants of the chiral pion-nucleon Lagrangian
15 pages, 13 eps figures, 2 tables
null
10.1140/epjc/s10052-014-2763-0
FTUAM-13-37, IFT-UAM/CSIC-13-127
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Positivity constraints on the pion-nucleon scattering amplitude are derived in this article with the help of general S-matrix arguments, such as analyticity, crossing symmetry and unitarity, in the upper part of Mandelstam triangle, R. Scanning inside the region R, the most stringent bounds on the chiral low energy constants of the pion-nucleon Lagrangian are determined. When just considering the central values of the fit results from covariant baryon chiral perturbation theory using extended-on-mass-shell scheme, it is found that these bounds are well respected numerically both at O(p^3) and O(p^4) level. Nevertheless, when taking the errors into account, only the O(p^4) bounds are obeyed in the full error interval, while the bounds on O(p^3) fits are slightly violated. If one disregards loop contributions, the bounds always fail in certain regions of R. Thus, at a given chiral order these terms are not numerically negligible and one needs to consider all possible contributions, i.e., both tree-level and loop diagrams. We have provided the constraints for special points in R where the bounds are nearly optimal in terms of just a few chiral couplings, which can be easily implemented and employed to constrain future analyses. Some issues about calculations with an explicit Delta(1232) resonance are also discussed.
[ { "created": "Tue, 3 Dec 2013 00:12:59 GMT", "version": "v1" } ]
2015-06-18
[ [ "Sanz-Cillero", "Juan Jose", "" ], [ "Yao", "De-Liang", "" ], [ "Zheng", "Han-Qing", "" ] ]
Positivity constraints on the pion-nucleon scattering amplitude are derived in this article with the help of general S-matrix arguments, such as analyticity, crossing symmetry and unitarity, in the upper part of Mandelstam triangle, R. Scanning inside the region R, the most stringent bounds on the chiral low energy constants of the pion-nucleon Lagrangian are determined. When just considering the central values of the fit results from covariant baryon chiral perturbation theory using extended-on-mass-shell scheme, it is found that these bounds are well respected numerically both at O(p^3) and O(p^4) level. Nevertheless, when taking the errors into account, only the O(p^4) bounds are obeyed in the full error interval, while the bounds on O(p^3) fits are slightly violated. If one disregards loop contributions, the bounds always fail in certain regions of R. Thus, at a given chiral order these terms are not numerically negligible and one needs to consider all possible contributions, i.e., both tree-level and loop diagrams. We have provided the constraints for special points in R where the bounds are nearly optimal in terms of just a few chiral couplings, which can be easily implemented and employed to constrain future analyses. Some issues about calculations with an explicit Delta(1232) resonance are also discussed.
hep-ph/0512005
Ahmed Ali
A. Ali, A.V. Borisov, D.V. Zhuridov
Effects of heavy Majorana neutrinos at lepton-proton colliders
5pages, 2 figures; published in conference proceedings: Particle Physics in Laboratory, Space and Universe, 11th. Lomonosov Conf. on Elementary Particle Physics (Moscow, 21-27 August 2003) (Singapore, World Scientific, 2005)
null
10.1142/9789812702074_0008
null
hep-ph
null
We discuss the prospects of detecting the processes $e^+p\to\bar\nu_e\ell^+\ell'^+X$ and $\nu_ep\to e\ell^+\ell'^+X$ ($\ell,\ell'=e,\mu,\tau$) under the conditions of the present $ep$ collider HERA and of future colliders. These high-energy processes are assumed to be mediated by the exchange of heavy Majorana neutrinos (HMN). We consider two simple scenarios for the HMN mass spectrum: the effective singlet ($m_1\ll m_2<m_3...$) and the effective doublet ($m_1<m_2\ll m_3...$). For the latter case, the cross section includes information about CP-violating phases.
[ { "created": "Thu, 1 Dec 2005 08:59:36 GMT", "version": "v1" } ]
2017-08-23
[ [ "Ali", "A.", "" ], [ "Borisov", "A. V.", "" ], [ "Zhuridov", "D. V.", "" ] ]
We discuss the prospects of detecting the processes $e^+p\to\bar\nu_e\ell^+\ell'^+X$ and $\nu_ep\to e\ell^+\ell'^+X$ ($\ell,\ell'=e,\mu,\tau$) under the conditions of the present $ep$ collider HERA and of future colliders. These high-energy processes are assumed to be mediated by the exchange of heavy Majorana neutrinos (HMN). We consider two simple scenarios for the HMN mass spectrum: the effective singlet ($m_1\ll m_2<m_3...$) and the effective doublet ($m_1<m_2\ll m_3...$). For the latter case, the cross section includes information about CP-violating phases.