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2403.11444
Linlin Huang
Linlin Huang, Yuanyuan Wang, He-Xu Zhang, Shinya Matsuzaki, Hiroyuki Ishida, Mamiya Kawaguchi, Akio Tomiya
Impact of local CP-odd domain in hot QCD on axionic domain-wall interpretation for NANOGrav 15-year Data
20 pages, 14 figures; a version accepted in Phys.Rev.D
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We argue that the axionic domain-wall with a QCD bias may be incompatible with the NANOGrav 15-year data on a stochastic gravitational wave (GW) background, when the domain wall network collapses in the hot-QCD induced local CP-odd domain. This is due to the drastic suppression of the QCD bias set by the QCD topological susceptibility in the presence of the CP-odd domain with nonzero $\theta$ parameter of order one which the QCD sphaleron could generate. We quantify the effect on the GW signals by working on a low-energy effective model of Nambu-Jona-Lasinio type in the mean field approximation. We find that only at $\theta=\pi$, the QCD bias tends to get significantly large enough due to the criticality of the thermal CP restoration, which would, however, give too big signal strengths to be consistent with the NANOGrav 15-year data and would also be subject to the strength of the phase transition at the criticality.
[ { "created": "Mon, 18 Mar 2024 03:41:51 GMT", "version": "v1" }, { "created": "Fri, 24 May 2024 01:59:05 GMT", "version": "v2" } ]
2024-05-27
[ [ "Huang", "Linlin", "" ], [ "Wang", "Yuanyuan", "" ], [ "Zhang", "He-Xu", "" ], [ "Matsuzaki", "Shinya", "" ], [ "Ishida", "Hiroyuki", "" ], [ "Kawaguchi", "Mamiya", "" ], [ "Tomiya", "Akio", "" ] ]
We argue that the axionic domain-wall with a QCD bias may be incompatible with the NANOGrav 15-year data on a stochastic gravitational wave (GW) background, when the domain wall network collapses in the hot-QCD induced local CP-odd domain. This is due to the drastic suppression of the QCD bias set by the QCD topological susceptibility in the presence of the CP-odd domain with nonzero $\theta$ parameter of order one which the QCD sphaleron could generate. We quantify the effect on the GW signals by working on a low-energy effective model of Nambu-Jona-Lasinio type in the mean field approximation. We find that only at $\theta=\pi$, the QCD bias tends to get significantly large enough due to the criticality of the thermal CP restoration, which would, however, give too big signal strengths to be consistent with the NANOGrav 15-year data and would also be subject to the strength of the phase transition at the criticality.
1204.5664
Sofian Teber
S. Teber
Electromagnetic current correlations in reduced quantum electrodynamics
(v2) Accepted for publication in PRD. Conclusion and references added (some / referee's comments). No change in results. 8 pages, 3 figures. (v1) LaTeX file with feynMF package. 8 pages, no figure
Phys. Rev. D 86, 025005 (2012)
10.1103/PhysRevD.86.025005
null
hep-ph cond-mat.str-el hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a theory of massless reduced quantum electrodynamics (RQED$_{d_\gamma,d_e}$), e.g., a quantum field theory where the U(1) gauge field lives in $d_\gamma$-spacetime dimensions while the fermionic field lives in a reduced spacetime of $d_e$ dimensions ($d_e \leqslant d_\gamma$). In the case where $d_\gamma=4$ such RQEDs are renormalizable while they are super-renormalizable for $d_\gamma <4$. The 2-loop electromagnetic current correlation function is computed exactly for a general RQED$_{d_\gamma,d_e}$. Focusing on RQED$_{4,3}$, the corresponding $\beta$-function is shown to vanish which implies the scale invariance of the theory. Interaction correction to the 1-loop vacuum polarization, $\Pi_1$, of RQED$_{4,3}$ is found to be: $\Pi = \Pi_1 (1 + 0.056 \al)$ where $\al$ is the fine structure constant. The scaling dimension of the fermion field is computed at 1-loop and is shown to be anomalous for RQED$_{4,3}$.
[ { "created": "Wed, 25 Apr 2012 14:14:59 GMT", "version": "v1" }, { "created": "Thu, 14 Jun 2012 17:58:15 GMT", "version": "v2" } ]
2012-11-12
[ [ "Teber", "S.", "" ] ]
We consider a theory of massless reduced quantum electrodynamics (RQED$_{d_\gamma,d_e}$), e.g., a quantum field theory where the U(1) gauge field lives in $d_\gamma$-spacetime dimensions while the fermionic field lives in a reduced spacetime of $d_e$ dimensions ($d_e \leqslant d_\gamma$). In the case where $d_\gamma=4$ such RQEDs are renormalizable while they are super-renormalizable for $d_\gamma <4$. The 2-loop electromagnetic current correlation function is computed exactly for a general RQED$_{d_\gamma,d_e}$. Focusing on RQED$_{4,3}$, the corresponding $\beta$-function is shown to vanish which implies the scale invariance of the theory. Interaction correction to the 1-loop vacuum polarization, $\Pi_1$, of RQED$_{4,3}$ is found to be: $\Pi = \Pi_1 (1 + 0.056 \al)$ where $\al$ is the fine structure constant. The scaling dimension of the fermion field is computed at 1-loop and is shown to be anomalous for RQED$_{4,3}$.
1706.02456
Debasish Borah
Debasish Borah, Arnab Dasgupta, Sudhanwa Patra
Neutrinoless double beta decay in minimal left-right symmetric model with universal seesaw
42 pages, 9 figures, to appear in Int. J. Mod. Phys. A
Int. J. Mod. Phys. A, 33 (2018) 1850198
10.1142/S0217751X18501981
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a detailed discussion on neutrinoless double beta decay $(0\nu \beta \beta)$ within left-right symmetric models based on the gauge symmetry of type $SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ as well as $SU(3)_L \times SU(3)_R \times U(1)_{X}$ where fermion masses including that of neutrinos are generated through a universal seesaw mechanism. We find that one or more of the right-handed neutrinos could be as light as a few keV if left-right symmetry breaking occurs in the range of a few TeV to 100 TeV. With such light right-handed neutrinos, we perform a detailed study of new physics contributions to $0\nu \beta \beta$ and constrain the model parameters from the latest experimental bound on such a rare decay process. We find that the new physics contribution to $0\nu \beta \beta$ in such a scenario, particularly the heavy-light neutrino mixing diagrams, can individually saturate the existing experimental bounds, but their contributions to total $0\nu \beta \beta$ half-life cancels each other due to unitarity of the total $6\times 6$ mass matrix. The effective contribution to half-life therefore, arises from the purely left and purely right neutrino and gauge boson mediated diagrams. We find that the parameter space saturating the $0\nu \beta \beta$ bounds remain allowed from the latest experimental bounds on charged lepton flavour violating decays like $\mu \rightarrow e \gamma$. We finally include the bounds from cosmology and supernova to constrain the parameter space of the model.
[ { "created": "Thu, 8 Jun 2017 06:32:41 GMT", "version": "v1" }, { "created": "Wed, 14 Nov 2018 16:47:39 GMT", "version": "v2" } ]
2019-01-07
[ [ "Borah", "Debasish", "" ], [ "Dasgupta", "Arnab", "" ], [ "Patra", "Sudhanwa", "" ] ]
We present a detailed discussion on neutrinoless double beta decay $(0\nu \beta \beta)$ within left-right symmetric models based on the gauge symmetry of type $SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ as well as $SU(3)_L \times SU(3)_R \times U(1)_{X}$ where fermion masses including that of neutrinos are generated through a universal seesaw mechanism. We find that one or more of the right-handed neutrinos could be as light as a few keV if left-right symmetry breaking occurs in the range of a few TeV to 100 TeV. With such light right-handed neutrinos, we perform a detailed study of new physics contributions to $0\nu \beta \beta$ and constrain the model parameters from the latest experimental bound on such a rare decay process. We find that the new physics contribution to $0\nu \beta \beta$ in such a scenario, particularly the heavy-light neutrino mixing diagrams, can individually saturate the existing experimental bounds, but their contributions to total $0\nu \beta \beta$ half-life cancels each other due to unitarity of the total $6\times 6$ mass matrix. The effective contribution to half-life therefore, arises from the purely left and purely right neutrino and gauge boson mediated diagrams. We find that the parameter space saturating the $0\nu \beta \beta$ bounds remain allowed from the latest experimental bounds on charged lepton flavour violating decays like $\mu \rightarrow e \gamma$. We finally include the bounds from cosmology and supernova to constrain the parameter space of the model.
1604.08206
Kathryn Zurek
Katelin Schutz, Kathryn M. Zurek
On the Detectability of Light Dark Matter with Superfluid Helium
5 pages, 2 figures. v2: added references, updated fig 2 and corresponding discussion with simulation data; conclusions unchanged
Phys. Rev. Lett. 117, 121302 (2016)
10.1103/PhysRevLett.117.121302
null
hep-ph astro-ph.CO cond-mat.other hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that a two-excitation process in superfluid helium, combined with sensitivity to meV energy depositions, can probe dark matter down to the ~keV warm dark matter mass limit. This mass reach is three orders of magnitude below what can be probed with ordinary nuclear recoils in helium at the same energy resolution. For dark matter lighter than $\sim 100$ keV, the kinematics of the process requires the two athermal excitations to have nearly equal and opposite momentum, potentially providing a built-in coincidence mechanism for controlling backgrounds.
[ { "created": "Wed, 27 Apr 2016 20:00:01 GMT", "version": "v1" }, { "created": "Fri, 5 Aug 2016 14:00:28 GMT", "version": "v2" } ]
2016-09-21
[ [ "Schutz", "Katelin", "" ], [ "Zurek", "Kathryn M.", "" ] ]
We show that a two-excitation process in superfluid helium, combined with sensitivity to meV energy depositions, can probe dark matter down to the ~keV warm dark matter mass limit. This mass reach is three orders of magnitude below what can be probed with ordinary nuclear recoils in helium at the same energy resolution. For dark matter lighter than $\sim 100$ keV, the kinematics of the process requires the two athermal excitations to have nearly equal and opposite momentum, potentially providing a built-in coincidence mechanism for controlling backgrounds.
hep-ph/0601108
Teruaki Suyama
Teruaki Suyama, Takahiro Tanaka, Bruce Bassett, Hideaki Kudoh
Black hole production in tachyonic preheating
6pages, 7figures, figures corrected
JCAP 0604 (2006) 001
10.1088/1475-7516/2006/04/001
null
hep-ph astro-ph hep-th
null
We present fully non-linear simulations of a self-interacting scalar field in the early universe undergoing tachyonic preheating. We find that density perturbations on sub-horizon scales which are amplified by tachyonic instability maintain long range correlations even during the succeeding parametric resonance, in contrast to the standard models of preheating dominated by parametric resonance. As a result the final spectrum exhibits memory and is not universal in shape. We find that throughout the subsequent era of parametric resonance the equation of state of the universe is almost dust-like, hence the Jeans wavelength is much smaller than the horizon scale. If our 2D simulations are accurate reflections of the situation in 3D, then there are wide regions of parameter space ruled out by over-production of black holes. It is likely however that realistic parameter values, consistent with COBE/WMAP normalisation, are safetly outside this black hole over-production region.
[ { "created": "Fri, 13 Jan 2006 11:46:01 GMT", "version": "v1" }, { "created": "Thu, 26 Jan 2006 09:15:24 GMT", "version": "v2" } ]
2009-11-11
[ [ "Suyama", "Teruaki", "" ], [ "Tanaka", "Takahiro", "" ], [ "Bassett", "Bruce", "" ], [ "Kudoh", "Hideaki", "" ] ]
We present fully non-linear simulations of a self-interacting scalar field in the early universe undergoing tachyonic preheating. We find that density perturbations on sub-horizon scales which are amplified by tachyonic instability maintain long range correlations even during the succeeding parametric resonance, in contrast to the standard models of preheating dominated by parametric resonance. As a result the final spectrum exhibits memory and is not universal in shape. We find that throughout the subsequent era of parametric resonance the equation of state of the universe is almost dust-like, hence the Jeans wavelength is much smaller than the horizon scale. If our 2D simulations are accurate reflections of the situation in 3D, then there are wide regions of parameter space ruled out by over-production of black holes. It is likely however that realistic parameter values, consistent with COBE/WMAP normalisation, are safetly outside this black hole over-production region.
1903.05973
Ye Xing
Ye Xing, Fu-Sheng Yu, Ruilin Zhu
Weak Decays of Stable Open-bottom Tetraquark by SU(3) Symmetry Analysis
53 pages, 2 figures
null
10.1140/epjc/s10052-019-6882-5
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The exotic state $X(5568)$ which was observed by D0 Collaboration is very likely to be a tetraquark state with four different valence quark flavors, though the existence was not confirmed by other collaborations. The possibility of such state still generate lots of interests in theory. In the paper, we will study the properties of the state under the SU(3) flavor symmetry. This four quark state with a heavy bottom quark and three light quarks(anti-quark) can form a $6$ or $\overline {15}$ representation. The weak decays can be dominant and should be discussed carefully while such state is stable against the strong interaction. Therefor we will study the multi-body semileptonic and nonleptonic weak decays systematically. With the help of SU(3) flavor symmetry, we can give the Hamiltonian in the hadronic level, then obtain the parameterized irreducible amplitudes and the relations of different channels. At the end of the article, we collect some Cabibbo allowed two-body and three-body weak decay channels which can be used to reconstruct $X_{b6}$ states at the branching fraction up to be $10^{-5}$.
[ { "created": "Thu, 14 Mar 2019 13:18:52 GMT", "version": "v1" } ]
2019-05-22
[ [ "Xing", "Ye", "" ], [ "Yu", "Fu-Sheng", "" ], [ "Zhu", "Ruilin", "" ] ]
The exotic state $X(5568)$ which was observed by D0 Collaboration is very likely to be a tetraquark state with four different valence quark flavors, though the existence was not confirmed by other collaborations. The possibility of such state still generate lots of interests in theory. In the paper, we will study the properties of the state under the SU(3) flavor symmetry. This four quark state with a heavy bottom quark and three light quarks(anti-quark) can form a $6$ or $\overline {15}$ representation. The weak decays can be dominant and should be discussed carefully while such state is stable against the strong interaction. Therefor we will study the multi-body semileptonic and nonleptonic weak decays systematically. With the help of SU(3) flavor symmetry, we can give the Hamiltonian in the hadronic level, then obtain the parameterized irreducible amplitudes and the relations of different channels. At the end of the article, we collect some Cabibbo allowed two-body and three-body weak decay channels which can be used to reconstruct $X_{b6}$ states at the branching fraction up to be $10^{-5}$.
hep-ph/9312323
null
K.G.Chetyrkin, O.V.Tarasov
The $\alpha_s^3$ Corrections to the Effective Neutral Current and to the Z Decay Rate in the Heavy Top Quark Limit
11 pages, LATEX, no figures, Preprint TTP93-38,INR-842/93 , December 1993
Phys.Lett. B327 (1994) 114-122
10.1016/0370-2693(94)91538-5
null
hep-ph
null
We find the effective neutral current in the heavy top quark limit up to and including the terms of order $\alpha_s^3$. The result is then employed to compute the correction of the same order to the axial part of the Z decay rate into hadrons ($\G^h_Z$) induced by the top-bottom quark mass splitting. The calculations confirm the prediction made in a previous work of K.G.Ch. and J.H.K\"uhn (Phys. Lett. B 308 (1993) 127), namely, the effect of the singlet corrections of order $\alpha^3_s$ to the axial part of the $\G^h_Z$ should not exceed 25\% - 30\% (depending on the values chosen for $\alpha_s(M_Z)$ and $m_t$) of the magnitude of the leading (singlet) $\alpha_s^2$ term.
[ { "created": "Tue, 21 Dec 1993 19:32:00 GMT", "version": "v1" } ]
2009-10-22
[ [ "Chetyrkin", "K. G.", "" ], [ "Tarasov", "O. V.", "" ] ]
We find the effective neutral current in the heavy top quark limit up to and including the terms of order $\alpha_s^3$. The result is then employed to compute the correction of the same order to the axial part of the Z decay rate into hadrons ($\G^h_Z$) induced by the top-bottom quark mass splitting. The calculations confirm the prediction made in a previous work of K.G.Ch. and J.H.K\"uhn (Phys. Lett. B 308 (1993) 127), namely, the effect of the singlet corrections of order $\alpha^3_s$ to the axial part of the $\G^h_Z$ should not exceed 25\% - 30\% (depending on the values chosen for $\alpha_s(M_Z)$ and $m_t$) of the magnitude of the leading (singlet) $\alpha_s^2$ term.
0908.3117
Stefan Recksiegel
Stefan Recksiegel
Flavour Physics in the Littlest Higgs Model with T-Parity: Effects in the K, B_d/s and D systems
Talk given at the Flavianet Workshop on Low energy constraints on extensions of the Standard Model, 23-27 July 2009, Kazimierz, Poland
null
10.1002/prop.201000004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Littlest Higgs Model with T parity (LHT) is an interesting alternative model for New Physics at the TeV scale. Although Flavour Physics was not the reason for creating the LHT model, significant effects (such as large CP violation where not predicted by the SM) can be created without violating existing experimental bounds. We study the B-, K- and especially the D-sector.
[ { "created": "Fri, 21 Aug 2009 12:52:24 GMT", "version": "v1" } ]
2015-05-14
[ [ "Recksiegel", "Stefan", "" ] ]
The Littlest Higgs Model with T parity (LHT) is an interesting alternative model for New Physics at the TeV scale. Although Flavour Physics was not the reason for creating the LHT model, significant effects (such as large CP violation where not predicted by the SM) can be created without violating existing experimental bounds. We study the B-, K- and especially the D-sector.
2008.04943
Martin Beneke
Martin Beneke, Mathias Garny, Sebastian Jaskiewicz, Robert Szafron, Leonardo Vernazza, Jian Wang
Large-x resummation of off-diagonal deep-inelastic parton scattering from d-dimensional refactorization
50 pages, LaTeX
null
10.1007/JHEP10(2020)196
TUM-HEP-1270/20, CERN-TH-2020-135
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The off-diagonal parton-scattering channels $g+\gamma^*$ and $q+\phi^*$ in deep-inelastic scattering are power-suppressed near threshold $x\to 1$. We address the next-to-leading power (NLP) resummation of large double logarithms of $1-x$ to all orders in the strong coupling, which are present even in the off-diagonal DGLAP splitting kernels. The appearance of divergent convolutions prevents the application of factorization methods known from leading power resummation. Employing $d$-dimensional consistency relations from requiring $1/\epsilon$ pole cancellations in dimensional regularization between momentum regions, we show that the resummation of the off-diagonal parton-scattering channels at the leading logarithmic order can be bootstrapped from the recently conjectured exponentiation of NLP soft-quark Sudakov logarithms. In particular, we derive a result for the DGLAP kernel in terms of the series of Bernoulli numbers found previously by Vogt directly from algebraic all-order expressions. We identify the off-diagonal DGLAP splitting functions and soft-quark Sudakov logarithms as inherent two-scale quantities in the large-$x$ limit. We use a refactorization of these scales and renormalization group methods inspired by soft-collinear effective theory to derive the conjectured soft-quark Sudakov exponentiation formula.
[ { "created": "Tue, 11 Aug 2020 18:12:24 GMT", "version": "v1" } ]
2020-12-02
[ [ "Beneke", "Martin", "" ], [ "Garny", "Mathias", "" ], [ "Jaskiewicz", "Sebastian", "" ], [ "Szafron", "Robert", "" ], [ "Vernazza", "Leonardo", "" ], [ "Wang", "Jian", "" ] ]
The off-diagonal parton-scattering channels $g+\gamma^*$ and $q+\phi^*$ in deep-inelastic scattering are power-suppressed near threshold $x\to 1$. We address the next-to-leading power (NLP) resummation of large double logarithms of $1-x$ to all orders in the strong coupling, which are present even in the off-diagonal DGLAP splitting kernels. The appearance of divergent convolutions prevents the application of factorization methods known from leading power resummation. Employing $d$-dimensional consistency relations from requiring $1/\epsilon$ pole cancellations in dimensional regularization between momentum regions, we show that the resummation of the off-diagonal parton-scattering channels at the leading logarithmic order can be bootstrapped from the recently conjectured exponentiation of NLP soft-quark Sudakov logarithms. In particular, we derive a result for the DGLAP kernel in terms of the series of Bernoulli numbers found previously by Vogt directly from algebraic all-order expressions. We identify the off-diagonal DGLAP splitting functions and soft-quark Sudakov logarithms as inherent two-scale quantities in the large-$x$ limit. We use a refactorization of these scales and renormalization group methods inspired by soft-collinear effective theory to derive the conjectured soft-quark Sudakov exponentiation formula.
0707.2623
Shi-Lin Zhu
Shi-Lin Zhu
Spectroscopy of Mesons with Heavy Quarks
Plenary talk at INPC2007, http://inpc2007.riken.jp/P/P5-zhu.pdf
Nucl.Phys.A805:221c-229c,2008
10.1016/j.nuclphysa.2008.02.251
null
hep-ph hep-ex nucl-th
null
I will give a concise overview of mesons with heavy quarks including p-wave charmed mesons and charmonium (or charmonium-like) states such as X(3872), Y(4260), X(3940), Y(3940), Z(3930) etc. The effect from the nearby S-wave open channels on the quark model spectrum is emphasized.
[ { "created": "Wed, 18 Jul 2007 02:03:49 GMT", "version": "v1" } ]
2008-11-26
[ [ "Zhu", "Shi-Lin", "" ] ]
I will give a concise overview of mesons with heavy quarks including p-wave charmed mesons and charmonium (or charmonium-like) states such as X(3872), Y(4260), X(3940), Y(3940), Z(3930) etc. The effect from the nearby S-wave open channels on the quark model spectrum is emphasized.
1512.02508
Rhorry Gauld
Rhorry Gauld, Benjamin D. Pecjak, and Darren J. Scott
One-loop corrections to $h\to b\bar b$ and $h\to \tau\bar \tau$ decays in the Standard Model Dimension-6 EFT: four-fermion operators and the large-$m_t$ limit
38 pages. Matches journal version and includes extended discussion in phenomenology section
null
10.1007/JHEP05(2016)080
DCPT/15/34, IPPP/15/17
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate a set of one-loop corrections to $h\to b\bar b$ and $h\to \tau\bar \tau$ decays in the dimension-6 Standard Model effective field theory (SMEFT). In particular, working in the limit of vanishing gauge couplings, we calculate directly in the broken phase of the theory all large logarithmic corrections and in addition the finite corrections in the large-$m_t$ limit. Moreover, we give exact results for one-loop contributions from four-fermion operators. We obtain these corrections within an extension of the widely used on-shell renormalisation scheme appropriate for SMEFT calculations, and show explicitly how UV divergent bare amplitudes from a total of 21 different SMEFT operators are rendered finite within this scheme. As a by-product of the calculation, we also compute to one-loop order the logarithmically enhanced and finite large-$m_t$ corrections to muon decay in the limit of vanishing gauge couplings, which is necessary to implement the $G_F$ input parameter scheme within the SMEFT.
[ { "created": "Tue, 8 Dec 2015 15:28:00 GMT", "version": "v1" }, { "created": "Wed, 19 Oct 2016 13:57:26 GMT", "version": "v2" } ]
2016-10-26
[ [ "Gauld", "Rhorry", "" ], [ "Pecjak", "Benjamin D.", "" ], [ "Scott", "Darren J.", "" ] ]
We calculate a set of one-loop corrections to $h\to b\bar b$ and $h\to \tau\bar \tau$ decays in the dimension-6 Standard Model effective field theory (SMEFT). In particular, working in the limit of vanishing gauge couplings, we calculate directly in the broken phase of the theory all large logarithmic corrections and in addition the finite corrections in the large-$m_t$ limit. Moreover, we give exact results for one-loop contributions from four-fermion operators. We obtain these corrections within an extension of the widely used on-shell renormalisation scheme appropriate for SMEFT calculations, and show explicitly how UV divergent bare amplitudes from a total of 21 different SMEFT operators are rendered finite within this scheme. As a by-product of the calculation, we also compute to one-loop order the logarithmically enhanced and finite large-$m_t$ corrections to muon decay in the limit of vanishing gauge couplings, which is necessary to implement the $G_F$ input parameter scheme within the SMEFT.
hep-ph/0505131
Zoltan Nagy
Zoltan Nagy
Matching Parton Showers to NLO Computation
Presented at the 40th Rencontres de Moriond ''QCD and Hadronic Interactions'', La Thuile, Aosta Valley, Italy, March 12th to 19th, 2005; 4 pages
null
10.1088/1126-6708/2005/10/024
null
hep-ph
null
In this review a new method is presented for attaching parton shower algorithms to NLO partonic jet cross sections in electron-positron annihilation. Our method is based on the Catani-Seymour dipole subtraction method and also uses an adaptation of the matching scheme of Catani, Krauss, Kuhn, and Webber.
[ { "created": "Sat, 14 May 2005 21:36:34 GMT", "version": "v1" } ]
2009-11-11
[ [ "Nagy", "Zoltan", "" ] ]
In this review a new method is presented for attaching parton shower algorithms to NLO partonic jet cross sections in electron-positron annihilation. Our method is based on the Catani-Seymour dipole subtraction method and also uses an adaptation of the matching scheme of Catani, Krauss, Kuhn, and Webber.
hep-ph/0504257
Angela Milliken
Gordon Kane
How Can We Go From Hadron Collider Data Toward the Underlying Theory That Extends the Standard Model? After the Champagne
9 pages, 2 figures, 1 table
Czech.J.Phys.55:B197-B204,2005
null
null
hep-ph hep-ex hep-th
null
This is a composite based on talks at Physics at LHC, Vienna, July 2004, TeV4LHC, Fermilab, Sept. 2004, and the String Phenomenology meeting, Perimeter Institute, March 2005.
[ { "created": "Wed, 27 Apr 2005 12:41:49 GMT", "version": "v1" } ]
2011-04-11
[ [ "Kane", "Gordon", "" ] ]
This is a composite based on talks at Physics at LHC, Vienna, July 2004, TeV4LHC, Fermilab, Sept. 2004, and the String Phenomenology meeting, Perimeter Institute, March 2005.
hep-ph/0509158
Marat Siddikov Ilfatovich
V. Guzey, M.Siddikov
On the A-dependence of nuclear generalized parton distributions
Final version published in J. Phys. G. 17 pages, 9 figures
J.Phys. G32 (2006) 251-268
10.1088/0954-3899/32/3/002
RUB-TPII-08/2005
hep-ph
null
We perform a microscopic evaluation of nuclear GPDs for spin-0 nuclei in the framework of the Walecka model. We demonstrate that the meson (non-nucleon) degrees of freedom dramatically influence nuclear GPDs, which is revealed in the non-trivial and unexpected A-dependence of DVCS observables. In particular, we find that the first moment of the nuclear D-term, d_A(0) ~ A^2.26, which confirms the earlier prediction of M.Polyakov. We find that in the HERMES kinematics, contrary to the free proton case, the nuclear meson degrees of freedom in large nuclei enhance the nuclear DVCS amplitude which becomes comparable to the Bethe-Heitler amplitude, and, thus, give the non-trivial A-dependence to the DVCS asymmetries: as a function of the atomic number the beam-charge asymmetry increases whereas the beam-spin asymmetry decreases slowly.
[ { "created": "Thu, 15 Sep 2005 14:33:49 GMT", "version": "v1" }, { "created": "Mon, 16 Jan 2006 09:22:34 GMT", "version": "v2" } ]
2007-05-23
[ [ "Guzey", "V.", "" ], [ "Siddikov", "M.", "" ] ]
We perform a microscopic evaluation of nuclear GPDs for spin-0 nuclei in the framework of the Walecka model. We demonstrate that the meson (non-nucleon) degrees of freedom dramatically influence nuclear GPDs, which is revealed in the non-trivial and unexpected A-dependence of DVCS observables. In particular, we find that the first moment of the nuclear D-term, d_A(0) ~ A^2.26, which confirms the earlier prediction of M.Polyakov. We find that in the HERMES kinematics, contrary to the free proton case, the nuclear meson degrees of freedom in large nuclei enhance the nuclear DVCS amplitude which becomes comparable to the Bethe-Heitler amplitude, and, thus, give the non-trivial A-dependence to the DVCS asymmetries: as a function of the atomic number the beam-charge asymmetry increases whereas the beam-spin asymmetry decreases slowly.
1912.12501
Alexander Studenikin
Alexander Studenikin
Electromagnetic neutrinos: New constraints and new effects in oscillations
4 pages in LaTex, to appear in the proceedings of the 16th International Conference on Topics in Astroparticle and Underground Physics (TAUP 2019), 9-13 September 2019, Toyama, Japan. arXiv admin note: substantial text overlap with arXiv:1801.08887, arXiv:1912.12497
Journal of Physics: Conference Series 1468 (2020) 012196
10.1088/1742-6596/1468/1/012196
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A short overview of neutrino electromagnetic properties with focus on existed experimental constraints and future prospects is presented. The related new effect in neutrino flavour and spin-flavour oscillations in the transversal matter currents is introduced.
[ { "created": "Sat, 28 Dec 2019 18:26:13 GMT", "version": "v1" } ]
2020-04-10
[ [ "Studenikin", "Alexander", "" ] ]
A short overview of neutrino electromagnetic properties with focus on existed experimental constraints and future prospects is presented. The related new effect in neutrino flavour and spin-flavour oscillations in the transversal matter currents is introduced.
hep-ph/0011054
Orlando Luis Goulart Peres
O. L. G. Peres and A. Yu. Smirnov
(3+1)-spectrum of neutrino masses: A chance for LSND?
41 pages, Latex, uses epsfig. Corrected misprints
Nucl.Phys. B599 (2001) 3
10.1016/S0550-3213(01)00012-8
null
hep-ph hep-ex
null
If active to active neutrino transitions are dominant modes of the atmospheric ($\nu_{\mu} \to \nu_{\tau}$) and the solar neutrino oscillations ($\nu_{e}\to \nu_{\mu}/\nu_{\tau}$), as is indicated by recent data, the favoured scheme which accommodates the LSND result - the so called (2+2)-scheme - should be discarded. We introduce the parameters $\eta_s^{atm}$ and $\eta_s^{sun}$ which quantify an involvement of the sterile component in the solar and atmospheric neutrino oscillations. The (2+2)-scheme predicts $\eta_s^{atm} + \eta_s^{sun} = 1$ and the experimental proof of deviation from this equality will discriminate the scheme. In this connection the (3+1)-scheme is revisited in which the fourth (predominantly sterile) neutrino is isolated from a block of three flavour neutrinos by the mass gap $\Delta m^2_{LSND} \sim (0.4-10)$ eV$^2$. We find that in the (3+1)-scheme the LSND result can be reconciled with existing bounds on $\nu_e$- and $\nu_{\mu}$ - disappearance at 95-99 % C.L.. The generic prediction of the scheme is the $\nu_e$- and $\nu_{\mu}$ - disappearance probabilities at the level of present experimental bounds. The possibility to strengthen the bound on $\nu_{\mu}$- disappearance in the KEK - front detector experiment is studied. We consider phenomenology of the (3 + 1)-scheme, in particular, its implications for the atmospheric neutrinos, neutrinoless double beta decay searches, supernova neutrinos and primordial nucleosynthesis.
[ { "created": "Fri, 3 Nov 2000 17:31:05 GMT", "version": "v1" }, { "created": "Wed, 15 Nov 2000 18:32:25 GMT", "version": "v2" }, { "created": "Mon, 22 Jan 2001 13:55:12 GMT", "version": "v3" } ]
2009-10-31
[ [ "Peres", "O. L. G.", "" ], [ "Smirnov", "A. Yu.", "" ] ]
If active to active neutrino transitions are dominant modes of the atmospheric ($\nu_{\mu} \to \nu_{\tau}$) and the solar neutrino oscillations ($\nu_{e}\to \nu_{\mu}/\nu_{\tau}$), as is indicated by recent data, the favoured scheme which accommodates the LSND result - the so called (2+2)-scheme - should be discarded. We introduce the parameters $\eta_s^{atm}$ and $\eta_s^{sun}$ which quantify an involvement of the sterile component in the solar and atmospheric neutrino oscillations. The (2+2)-scheme predicts $\eta_s^{atm} + \eta_s^{sun} = 1$ and the experimental proof of deviation from this equality will discriminate the scheme. In this connection the (3+1)-scheme is revisited in which the fourth (predominantly sterile) neutrino is isolated from a block of three flavour neutrinos by the mass gap $\Delta m^2_{LSND} \sim (0.4-10)$ eV$^2$. We find that in the (3+1)-scheme the LSND result can be reconciled with existing bounds on $\nu_e$- and $\nu_{\mu}$ - disappearance at 95-99 % C.L.. The generic prediction of the scheme is the $\nu_e$- and $\nu_{\mu}$ - disappearance probabilities at the level of present experimental bounds. The possibility to strengthen the bound on $\nu_{\mu}$- disappearance in the KEK - front detector experiment is studied. We consider phenomenology of the (3 + 1)-scheme, in particular, its implications for the atmospheric neutrinos, neutrinoless double beta decay searches, supernova neutrinos and primordial nucleosynthesis.
1709.07331
Ivan Aleksandrov
I. A. Aleksandrov, G. Plunien, V. M. Shabaev
Momentum distribution of particles created in space-time-dependent colliding laser pulses
8 pages, 9 figures (including proof corrections)
Phys. Rev. D 96, 076006 (2017)
10.1103/PhysRevD.96.076006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the pair-production process in the presence of two counterpropagating linearly polarized short laser pulses. By means of a nonperturbative technique, we take into account the full coordinate dependence of the external field going beyond the dipole and standing-wave approximations. In particular, we analyze the momentum distribution of particles created. It is demonstrated that the spatial variations of the laser pulses may play a crucial role. The more accurate treatment reveals a number of prominent features: the pair-production probabilities become considerably smaller, the quantitative behavior of the momentum spectra changes dramatically, and the pulse shape effects become much less pronounced. The results of our study are expected to be very important for future theoretical and experimental investigations.
[ { "created": "Thu, 21 Sep 2017 13:58:58 GMT", "version": "v1" }, { "created": "Thu, 9 Nov 2017 16:12:50 GMT", "version": "v2" } ]
2017-11-10
[ [ "Aleksandrov", "I. A.", "" ], [ "Plunien", "G.", "" ], [ "Shabaev", "V. M.", "" ] ]
We study the pair-production process in the presence of two counterpropagating linearly polarized short laser pulses. By means of a nonperturbative technique, we take into account the full coordinate dependence of the external field going beyond the dipole and standing-wave approximations. In particular, we analyze the momentum distribution of particles created. It is demonstrated that the spatial variations of the laser pulses may play a crucial role. The more accurate treatment reveals a number of prominent features: the pair-production probabilities become considerably smaller, the quantitative behavior of the momentum spectra changes dramatically, and the pulse shape effects become much less pronounced. The results of our study are expected to be very important for future theoretical and experimental investigations.
1101.5175
Thomas Mehen
Thomas Mehen and Roxanne Springer (Duke U.)
Radiative Decays X(3872) -> psi(2S)+gamma and psi(4040) -> X(3872)+gamma in Effective Field Theory
13 pages, 4 figures
Phys.Rev.D83:094009,2011
10.1103/PhysRevD.83.094009
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Heavy hadron chiral perturbation theory (HHchiPT) and XEFT are applied to the decays X(3872) -> psi(2S) + gamma and psi(4040) -> X(3872) + gamma under the assumption that the X(3872) is a molecular bound state of neutral charm mesons. In these decays the emitted photon energies are 181 MeV and 165 MeV, respectively, so HHchiPT can be used to calculate the underlying D^0 bar{D}^{0*}+ bar{D}^0 D^{0*} -> psi(2S) + gamma or psi(4040) -> (D^0 bar{D}^{0*}+ bar{D}^0 D^{0*}) + gamma transition. These amplitudes are matched onto XEFT to obtain decay rates. The decays receive contributions from both long distance and short distance processes. We study the polarization of the psi(2S) in the decay X(3872) -> psi(2S) + gamma and the angular distribution of X(3872) in the decay psi(4040) -> X(3872) + gamma and find they can be used to differentiate between different decay mechanisms as well as discriminate between 2^{-+} and 1^{++} quantum number assignments of the X(3872).
[ { "created": "Wed, 26 Jan 2011 21:50:00 GMT", "version": "v1" } ]
2015-03-18
[ [ "Mehen", "Thomas", "", "Duke U." ], [ "Springer", "Roxanne", "", "Duke U." ] ]
Heavy hadron chiral perturbation theory (HHchiPT) and XEFT are applied to the decays X(3872) -> psi(2S) + gamma and psi(4040) -> X(3872) + gamma under the assumption that the X(3872) is a molecular bound state of neutral charm mesons. In these decays the emitted photon energies are 181 MeV and 165 MeV, respectively, so HHchiPT can be used to calculate the underlying D^0 bar{D}^{0*}+ bar{D}^0 D^{0*} -> psi(2S) + gamma or psi(4040) -> (D^0 bar{D}^{0*}+ bar{D}^0 D^{0*}) + gamma transition. These amplitudes are matched onto XEFT to obtain decay rates. The decays receive contributions from both long distance and short distance processes. We study the polarization of the psi(2S) in the decay X(3872) -> psi(2S) + gamma and the angular distribution of X(3872) in the decay psi(4040) -> X(3872) + gamma and find they can be used to differentiate between different decay mechanisms as well as discriminate between 2^{-+} and 1^{++} quantum number assignments of the X(3872).
hep-ph/9402288
Mannel Thomas
Thomas Mannel and Matthias Neubert
Resummation of Nonperturbative Corrections to the Lepton Spectrum in Inclusive $B\to X\,\ell\,\bar\nu$ Decays
22 pages, five figures appended after \end{document} as uu-encoded and compressed eps files, uses epsf, CERN-TH.7156/94
Phys.Rev.D50:2037-2047,1994
10.1103/PhysRevD.50.2037
null
hep-ph
null
We apply the operator product expansion to resum the leading nonperturbative corrections to the endpoint region of the lepton spectrum in inclusive semileptonic $B\to X_q\,\ell\,\bar\nu$ decays, taking into account a finite quark mass $m_q$ in the final state. We show that both for $b\to c$ and $b\to u$ transitions, it is consistent to describe these effects by a convolution of the parton model spectrum with a fundamental light-cone structure function. The moments of this function are proportional to forward matrix elements of higher-dimension operators. The prospects for an extraction of the structure function from a measurement of the lepton spectrum are discussed.
[ { "created": "Tue, 15 Feb 1994 10:35:49 GMT", "version": "v1" } ]
2011-07-19
[ [ "Mannel", "Thomas", "" ], [ "Neubert", "Matthias", "" ] ]
We apply the operator product expansion to resum the leading nonperturbative corrections to the endpoint region of the lepton spectrum in inclusive semileptonic $B\to X_q\,\ell\,\bar\nu$ decays, taking into account a finite quark mass $m_q$ in the final state. We show that both for $b\to c$ and $b\to u$ transitions, it is consistent to describe these effects by a convolution of the parton model spectrum with a fundamental light-cone structure function. The moments of this function are proportional to forward matrix elements of higher-dimension operators. The prospects for an extraction of the structure function from a measurement of the lepton spectrum are discussed.
2006.03383
Yoshihiro Shigekami
Shao-Long Chen, Amit Dutta Banik, Zhaofeng Kang, Qin Qin, Yoshihiro Shigekami
Signatures of a Flavor Changing $Z'$ Boson in $B_q \to \gamma Z'$
23 pages, 14 figures
null
10.1016/j.nuclphysb.2020.115237
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Rare $B$ meson decays offer an opportunity to probe a light hidden $Z'$ boson. In this work we explore a new channel $B_q \to \gamma Z'$ ($q = d, s$) followed by a cascade decay of $Z'$ into an invisible (neutrino or dark matter) or charged lepton pair $\ell^+ \ell^-$ ($\ell=e ,\mu)$. The study is based on a simplified effective model where the down quark sector has tiny flavor-changing neutral current couplings with $Z'$. For the first time, we calculate ${\rm BR}(B_q \to \gamma Z')$ at the leading power of $1/m_b$ and $1/E_\gamma$. Confronting with the strong constraints from semi-invisible decays of $B$ meson, we find that the branching ratio for $B_d \to {\rm invisible} + \gamma$ can be larger than its Standard Model prediction, leaving a large room for new physics, in particular for light dark matter. Additionally, the branching ratio for $B_d \to e^+ e^- \gamma$ can also be sizable when the corresponding flavor violating $Z'$ coupling to quarks is of the axial-vector type. On the other hand, the predicted branching ratios of $B_d \to \mu^+ \mu^- \gamma$ and $B_s \to \ell^+ \ell^- \gamma$ are severely constrained by the experimental measurements.
[ { "created": "Fri, 5 Jun 2020 11:43:04 GMT", "version": "v1" }, { "created": "Mon, 15 Jun 2020 07:03:41 GMT", "version": "v2" } ]
2020-12-30
[ [ "Chen", "Shao-Long", "" ], [ "Banik", "Amit Dutta", "" ], [ "Kang", "Zhaofeng", "" ], [ "Qin", "Qin", "" ], [ "Shigekami", "Yoshihiro", "" ] ]
Rare $B$ meson decays offer an opportunity to probe a light hidden $Z'$ boson. In this work we explore a new channel $B_q \to \gamma Z'$ ($q = d, s$) followed by a cascade decay of $Z'$ into an invisible (neutrino or dark matter) or charged lepton pair $\ell^+ \ell^-$ ($\ell=e ,\mu)$. The study is based on a simplified effective model where the down quark sector has tiny flavor-changing neutral current couplings with $Z'$. For the first time, we calculate ${\rm BR}(B_q \to \gamma Z')$ at the leading power of $1/m_b$ and $1/E_\gamma$. Confronting with the strong constraints from semi-invisible decays of $B$ meson, we find that the branching ratio for $B_d \to {\rm invisible} + \gamma$ can be larger than its Standard Model prediction, leaving a large room for new physics, in particular for light dark matter. Additionally, the branching ratio for $B_d \to e^+ e^- \gamma$ can also be sizable when the corresponding flavor violating $Z'$ coupling to quarks is of the axial-vector type. On the other hand, the predicted branching ratios of $B_d \to \mu^+ \mu^- \gamma$ and $B_s \to \ell^+ \ell^- \gamma$ are severely constrained by the experimental measurements.
2211.01789
Daiki Suenaga
Daiki Suenaga, Kotaro Murakami, Etsuko Itou, and Kei Iida
Probing the hadron mass spectrum in dense two-color QCD with the linear sigma model
16 pages, 6 figures
Phys.Rev.D 107, 054001 (2023)
10.1103/PhysRevD.107.054001
RIKEN-iTHEMS-Report-22, YITP-22-127
hep-ph hep-lat nucl-th
http://creativecommons.org/licenses/by/4.0/
We investigate modifications of hadron masses at finite quark chemical potential in two-flavor and two-color QCD, of which the data are available from lattice simulations, within a linear sigma model based on approximate Pauli-Gursey $SU(4)$ symmetry. The model describes not only ground-state scalar diquarks and pseudo-scalar mesons but also the excited pseudo-scalar diquarks and scalar mesons; each ground-state diquark (meson) has the corresponding excited diquark (hadron) with opposite parity as a chiral partner. Effects of chiral symmetry breaking and diquark condensates are incorporated by a mean-field treatment. We show that various mixings among the hadrons, which are triggered by the breakdown of baryon number conservation in the superfluid phase, lead to a rich hadron mass spectrum. We discuss the influence of $U(1)_A$ anomaly on the density dependence of the mass spectrum and also manifestations of the chiral partner structures as density increases in the superfluid phase. The predicted hadron masses are expected to provide future lattice simulations with useful information on such symmetry properties in dense two-color QCD.
[ { "created": "Thu, 3 Nov 2022 13:23:25 GMT", "version": "v1" }, { "created": "Fri, 3 Mar 2023 07:08:36 GMT", "version": "v2" } ]
2023-03-06
[ [ "Suenaga", "Daiki", "" ], [ "Murakami", "Kotaro", "" ], [ "Itou", "Etsuko", "" ], [ "Iida", "Kei", "" ] ]
We investigate modifications of hadron masses at finite quark chemical potential in two-flavor and two-color QCD, of which the data are available from lattice simulations, within a linear sigma model based on approximate Pauli-Gursey $SU(4)$ symmetry. The model describes not only ground-state scalar diquarks and pseudo-scalar mesons but also the excited pseudo-scalar diquarks and scalar mesons; each ground-state diquark (meson) has the corresponding excited diquark (hadron) with opposite parity as a chiral partner. Effects of chiral symmetry breaking and diquark condensates are incorporated by a mean-field treatment. We show that various mixings among the hadrons, which are triggered by the breakdown of baryon number conservation in the superfluid phase, lead to a rich hadron mass spectrum. We discuss the influence of $U(1)_A$ anomaly on the density dependence of the mass spectrum and also manifestations of the chiral partner structures as density increases in the superfluid phase. The predicted hadron masses are expected to provide future lattice simulations with useful information on such symmetry properties in dense two-color QCD.
1601.03469
M.I. Vyazovsky
M.A. Braun and M.I. Vyazovsky (Saint-Petersburg State University, Russia)
Reggeon-gluon vertices with Ward identities
19 pages, 7 figures; to be published in Phys. Rev. D
Phys. Rev. D 93, 065026 (2016)
10.1103/PhysRevD.93.065026
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ward identities for reggeons are studied in the framework of effective action approach to the QCD in Regge kinematics. It is shown that they require introduction of new contributions not present in the reggeon diagrams initially. Application to vertices RR$\to$RP and RR$\to$RRP are considered and diagrams which have to be added to the QCD ones are found.
[ { "created": "Thu, 14 Jan 2016 02:51:58 GMT", "version": "v1" }, { "created": "Fri, 12 Feb 2016 17:50:07 GMT", "version": "v2" }, { "created": "Sun, 28 Feb 2016 18:39:29 GMT", "version": "v3" } ]
2016-03-23
[ [ "Braun", "M. A.", "", "Saint-Petersburg State University,\n Russia" ], [ "Vyazovsky", "M. I.", "", "Saint-Petersburg State University,\n Russia" ] ]
Ward identities for reggeons are studied in the framework of effective action approach to the QCD in Regge kinematics. It is shown that they require introduction of new contributions not present in the reggeon diagrams initially. Application to vertices RR$\to$RP and RR$\to$RRP are considered and diagrams which have to be added to the QCD ones are found.
hep-ph/9506421
Mike Seymour
Michael H. Seymour, CERN
Jets in QCD
20 pages, 13 figures, typeset using REVTeX and aipbook.sty, slightly reformatted to improve page breaks. Talk given at the 10th Topical Workshop on Proton-Antiproton Collider Physics, Batavia, IL, May 9-13, 1995. A postscript version of this paper can be obtained from http://surya11.cern.ch/users/seymour/pubs/pbarp.ps.Z
AIP Conf.Proc.357:568-587,1996
10.1063/1.49625
CERN-TH/95-176
hep-ph
null
Many analyses at the collider utilize the hadronic jets that are the footprints of QCD partons. These are used both to study the QCD processes themselves and increasingly as tools to study other physics, for example top mass reconstruction. However, jets are not fundamental degrees of freedom in the theory, so we need an {\em operational jet definition} and {\em reliable methods to calculate their properties}. This talk covers both of these important areas of jet physics.
[ { "created": "Mon, 26 Jun 1995 13:30:52 GMT", "version": "v1" }, { "created": "Wed, 28 Jun 1995 16:29:21 GMT", "version": "v2" } ]
2014-11-17
[ [ "Seymour", "Michael H.", "" ], [ "CERN", "", "" ] ]
Many analyses at the collider utilize the hadronic jets that are the footprints of QCD partons. These are used both to study the QCD processes themselves and increasingly as tools to study other physics, for example top mass reconstruction. However, jets are not fundamental degrees of freedom in the theory, so we need an {\em operational jet definition} and {\em reliable methods to calculate their properties}. This talk covers both of these important areas of jet physics.
1801.07557
Eduard Seifert
Eduard Seifert, Wolfgang Cassing
Baryon-antibaryon dynamics in relativistic heavy-ion collisions
12 pages, 12 figures; Subsection III B added; Phys. Rev. C, in print
Phys. Rev. C 97, 044907 (2018)
10.1103/PhysRevC.97.044907
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The dynamics of baryon-antibaryon annihilation and reproduction ($B{\bar B} \leftrightarrow 3 M$) is studied within the Parton-Hadron-String Dynamics (PHSD) transport approach for Pb+Pb and Au+Au collisions as a function of centrality from lower Super Proton Synchrotron (SPS) up to Large Hadron Collider (LHC) energies on the basis of the quark rearrangement model (QRM). At Relativistic Heavy-Ion Collider (RHIC) energies we find a small net reduction of baryon-antibaryon ($B {\bar B}$) pairs while for the LHC energy of $\sqrt{s_{NN}}$ = 2.76 GeV a small net enhancement is found relative to calculations without annihilation (and reproduction) channels. Accordingly, the sizeable difference between data and statistical calculations in Pb+Pb collisions at $\sqrt{s_{NN}}$= 2.76 TeV for proton and antiproton yields \cite{53}, where a deviation of 2.7 $\sigma$ was claimed by the ALICE Collaboration, should not be attributed to a net antiproton annihilation. This is in line with the observation that no substantial deviation between the data and statistical hadronization model (SHM) calculations is seen for antihyperons, since according to the PHSD analysis the antihyperons should be modified by the same amount as antiprotons. As the PHSD results for particle ratios are in line with the ALICE data (within error bars) this might point towards a deviation from statistical equilibrium in the hadronization (at least for protons/antiprotons). Furthermore, we find that the $B {\bar B} \leftrightarrow 3 M$ reactions are more effective at lower SPS energies where a net suppression for antiprotons and antihyperons up to a factor of 2 -- 2.5 can be extracted from the PHSD calculations for central Au+Au collisions.
[ { "created": "Tue, 23 Jan 2018 14:26:03 GMT", "version": "v1" }, { "created": "Tue, 3 Apr 2018 12:51:26 GMT", "version": "v2" } ]
2018-04-25
[ [ "Seifert", "Eduard", "" ], [ "Cassing", "Wolfgang", "" ] ]
The dynamics of baryon-antibaryon annihilation and reproduction ($B{\bar B} \leftrightarrow 3 M$) is studied within the Parton-Hadron-String Dynamics (PHSD) transport approach for Pb+Pb and Au+Au collisions as a function of centrality from lower Super Proton Synchrotron (SPS) up to Large Hadron Collider (LHC) energies on the basis of the quark rearrangement model (QRM). At Relativistic Heavy-Ion Collider (RHIC) energies we find a small net reduction of baryon-antibaryon ($B {\bar B}$) pairs while for the LHC energy of $\sqrt{s_{NN}}$ = 2.76 GeV a small net enhancement is found relative to calculations without annihilation (and reproduction) channels. Accordingly, the sizeable difference between data and statistical calculations in Pb+Pb collisions at $\sqrt{s_{NN}}$= 2.76 TeV for proton and antiproton yields \cite{53}, where a deviation of 2.7 $\sigma$ was claimed by the ALICE Collaboration, should not be attributed to a net antiproton annihilation. This is in line with the observation that no substantial deviation between the data and statistical hadronization model (SHM) calculations is seen for antihyperons, since according to the PHSD analysis the antihyperons should be modified by the same amount as antiprotons. As the PHSD results for particle ratios are in line with the ALICE data (within error bars) this might point towards a deviation from statistical equilibrium in the hadronization (at least for protons/antiprotons). Furthermore, we find that the $B {\bar B} \leftrightarrow 3 M$ reactions are more effective at lower SPS energies where a net suppression for antiprotons and antihyperons up to a factor of 2 -- 2.5 can be extracted from the PHSD calculations for central Au+Au collisions.
1604.01127
Natsumi Nagata
Tony Gherghetta, Natsumi Nagata, and Mikhail Shifman
A Visible QCD Axion from an Enlarged Color Group
27 pages, 3 figures; v2: minor corrections, an explanatory remark and references added; v3: journal version
Phys. Rev. D 93, 115010 (2016)
10.1103/PhysRevD.93.115010
UMN-TH-3522/16, FTPI-MINN-16/11
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the possibility of an enlarged QCD color group, SU(3+$N^\prime$) spontaneously broken to SU(3)$_c\times$SU($N^\prime$) with extra vector-like quarks transforming in the fundamental representation. When the heavy quarks are integrated out below the PQ-breaking scale, they generate an axion coupling which simultaneously solves the strong CP problem for both gauge groups. However, the axion mass now receives a new nonperturbative contribution from the SU($N^\prime$) confinement scale, which can be substantially larger than the QCD scale. This can increase the axion mass to be at or above the electroweak scale. This visible axion can then decay into gluons and photons giving rise to observable signals at Run-II of the LHC. In particular, if the mass is identified with the 750 GeV diphoton resonance then the new confinement scale is $\sim$ TeV and the PQ-breaking scale is $\sim$ 10 TeV. This predicts vector-like quarks and a PQ scalar resonance in the multi-TeV range, with the possibility that dark matter is an SU($N^\prime$) baryon.
[ { "created": "Tue, 5 Apr 2016 03:44:55 GMT", "version": "v1" }, { "created": "Sat, 7 May 2016 02:54:58 GMT", "version": "v2" }, { "created": "Sat, 11 Jun 2016 16:55:53 GMT", "version": "v3" } ]
2016-06-15
[ [ "Gherghetta", "Tony", "" ], [ "Nagata", "Natsumi", "" ], [ "Shifman", "Mikhail", "" ] ]
We consider the possibility of an enlarged QCD color group, SU(3+$N^\prime$) spontaneously broken to SU(3)$_c\times$SU($N^\prime$) with extra vector-like quarks transforming in the fundamental representation. When the heavy quarks are integrated out below the PQ-breaking scale, they generate an axion coupling which simultaneously solves the strong CP problem for both gauge groups. However, the axion mass now receives a new nonperturbative contribution from the SU($N^\prime$) confinement scale, which can be substantially larger than the QCD scale. This can increase the axion mass to be at or above the electroweak scale. This visible axion can then decay into gluons and photons giving rise to observable signals at Run-II of the LHC. In particular, if the mass is identified with the 750 GeV diphoton resonance then the new confinement scale is $\sim$ TeV and the PQ-breaking scale is $\sim$ 10 TeV. This predicts vector-like quarks and a PQ scalar resonance in the multi-TeV range, with the possibility that dark matter is an SU($N^\prime$) baryon.
hep-ph/9504218
Sasaki Ken
Kuninori Horikawa and Ken Sasaki
Muonium-Antimuonium Conversion in Models with Dilepton Gauge Bosons
12 pages, plain LATEX, 3 figures not included, available upon request from the authors
Phys.Rev. D53 (1996) 560-563
10.1103/PhysRevD.53.560
YNU-HEPTh-107
hep-ph
null
We examine the magnetic field dependence of the muonium($\mu^+ e^-$) - antimuonium($\mu^- e^+$) conversion in the models which accommodate the dilepton gauge bosons. The effective Hamiltonian for the conversion due to dileptons turns out to be in the $(V-A)\times(V+A)$ form and, in consequence, the conversion probability is rather insensitive to the strength of the magnetic field. The reduction is less than $20\%$ for up to $B \approx 300$ G and $33\%$ even in the large $B$ limit.
[ { "created": "Tue, 4 Apr 1995 15:48:35 GMT", "version": "v1" } ]
2009-10-28
[ [ "Horikawa", "Kuninori", "" ], [ "Sasaki", "Ken", "" ] ]
We examine the magnetic field dependence of the muonium($\mu^+ e^-$) - antimuonium($\mu^- e^+$) conversion in the models which accommodate the dilepton gauge bosons. The effective Hamiltonian for the conversion due to dileptons turns out to be in the $(V-A)\times(V+A)$ form and, in consequence, the conversion probability is rather insensitive to the strength of the magnetic field. The reduction is less than $20\%$ for up to $B \approx 300$ G and $33\%$ even in the large $B$ limit.
1201.5702
Shigeru Odaka
Shigeru Odaka
GR@PPA 2.8.3 update
6 pages, 2 figures; minor changes
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
GR@PPA 2.8 is a program package including event generators for single and double weak-boson production processes at hadron collisions, in which a jet matching method is implemented for simulating the weak-boson kinematics in the entire phase space. Since the initial release in November, 2010, several improvements have been applied to the program components. This report describes the improvements and changes applied so far, up to the 2.8.3 release.
[ { "created": "Fri, 27 Jan 2012 05:22:52 GMT", "version": "v1" }, { "created": "Fri, 17 Feb 2012 03:06:07 GMT", "version": "v2" } ]
2012-02-20
[ [ "Odaka", "Shigeru", "" ] ]
GR@PPA 2.8 is a program package including event generators for single and double weak-boson production processes at hadron collisions, in which a jet matching method is implemented for simulating the weak-boson kinematics in the entire phase space. Since the initial release in November, 2010, several improvements have been applied to the program components. This report describes the improvements and changes applied so far, up to the 2.8.3 release.
2307.04236
Peihong Gu
Pei-Hong Gu
Heavy axions from twin dark sectors with $\bar{\theta}$-characterized mirror symmetry
4 pages. arXiv admin note: text overlap with arXiv:2211.11730
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The QCD Lagrangian contains a CP violating gluon density term with a physical coefficient $\bar{\theta}$. The upper bound on the electric dipole moment of neutron implies that the value of $\bar{\theta}$ should be extremely small rather than the theoretically expected order of unity. The tiny $\bar{\theta}$ is commonly known as the strong CP problem. In order to solve this puzzle, we construct a $\bar{\theta}$-characterized mirror symmetry between a pair of twin dark sectors with respective discrete symmetries. By taking a proper phase rotation of dark fields, we can perfectly remove the parameter $\bar{\theta}$ from the full Lagrangian. In our scenario, the discrete symmetry breaking, which are responsible for the mass generation of dark colored fermions and dark matter fermions, can be allowed near the TeV scale. This means different phenomena from the popular axion models with high scale Peccei-Quinn global symmetry breaking.
[ { "created": "Sun, 9 Jul 2023 17:53:32 GMT", "version": "v1" } ]
2023-07-11
[ [ "Gu", "Pei-Hong", "" ] ]
The QCD Lagrangian contains a CP violating gluon density term with a physical coefficient $\bar{\theta}$. The upper bound on the electric dipole moment of neutron implies that the value of $\bar{\theta}$ should be extremely small rather than the theoretically expected order of unity. The tiny $\bar{\theta}$ is commonly known as the strong CP problem. In order to solve this puzzle, we construct a $\bar{\theta}$-characterized mirror symmetry between a pair of twin dark sectors with respective discrete symmetries. By taking a proper phase rotation of dark fields, we can perfectly remove the parameter $\bar{\theta}$ from the full Lagrangian. In our scenario, the discrete symmetry breaking, which are responsible for the mass generation of dark colored fermions and dark matter fermions, can be allowed near the TeV scale. This means different phenomena from the popular axion models with high scale Peccei-Quinn global symmetry breaking.
hep-ph/0606196
Qiang Zhao
Qiang Zhao and Bing-Song Zou
On the near-threshold enhancement in $J/\psi\to \gamma X$ with $X\to\omega\phi$
12 pages, 6 figures; Version to appear in Phys. Rev. D
Phys.Rev.D74:114025,2006
10.1103/PhysRevD.74.114025
null
hep-ph hep-ex nucl-th
null
We investigate the possibility of producing the enhancement observed in $J/\psi\to \gamma X$ with $X\to \omega\phi $ at BES by intermediate meson rescatterings through $f_0(1710)\to PP\to \omega\phi$, $f_0(1710)\to VV\to \omega\phi$, and $f_0(1710)\to SS\to \omega\phi$. We find that intermediate meson rescatterings can produce some enhancement near the $\omega\phi$ threshold. Implications about the property of this enhancement are discussed.
[ { "created": "Mon, 19 Jun 2006 13:14:54 GMT", "version": "v1" }, { "created": "Wed, 6 Dec 2006 19:32:22 GMT", "version": "v2" } ]
2008-11-26
[ [ "Zhao", "Qiang", "" ], [ "Zou", "Bing-Song", "" ] ]
We investigate the possibility of producing the enhancement observed in $J/\psi\to \gamma X$ with $X\to \omega\phi $ at BES by intermediate meson rescatterings through $f_0(1710)\to PP\to \omega\phi$, $f_0(1710)\to VV\to \omega\phi$, and $f_0(1710)\to SS\to \omega\phi$. We find that intermediate meson rescatterings can produce some enhancement near the $\omega\phi$ threshold. Implications about the property of this enhancement are discussed.
1701.02906
Anthony Hartin
A. Hartin
Second Order QED Processes in an Intense Electromagnetic Field
The bulk of this 2006 PhD thesis comes from research performed during 1986-1994. Chapter 8 was added in 2005. Errata has been corrected in the intervening years
British Library, EThOS uk.bl.ethos.436336 2006
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Some non linear, second order QED processes in the presence of intense plane electromagnetic waves are investigated. Analytic expressions with general kinematics are derived for Compton scattering and $e^+e^-$ pair production in a circularly polarised external electromagnetic field. The differential cross sections were investigated numerically for photon energies up to 50 MeV, external field intensity parameter $\nu^2$ to value 2, and all scattering angles. The variation of full cross sections with respect to external field intensity was also established. The presence of the external field led to resonances in the Compton scattering and pair production differential cross sections. These resonances were investigated by calculating the electron self energy in the presence of the external field. At resonance the differential cross sections were enhanced by several orders of magnitude. The resonances occurred for values of external field intensity parameter $\nu^2 <1$, lowering the limit of $\nu^2 \sim 1$ at which point non linear effects in first order external field QED processes become important. Generally, full cross sections increased with increasing external field intensity, though peaking sharply for Compton scattering and levelling off for pair production. An application was made to non linear background studies at $e^+e^-$ linear colliders. The pair production process and electron self energy were studied for the case of a constant crossed electromagnetic field. It was found that previous analytic expressions required the external field to be azimuthally symmetric. New analytic expressions for the more general non azimuthally symmetric case were developed and a numerical parameter range equivalent to that proposed for future linear collider designs was considered.
[ { "created": "Wed, 11 Jan 2017 09:52:12 GMT", "version": "v1" } ]
2017-01-12
[ [ "Hartin", "A.", "" ] ]
Some non linear, second order QED processes in the presence of intense plane electromagnetic waves are investigated. Analytic expressions with general kinematics are derived for Compton scattering and $e^+e^-$ pair production in a circularly polarised external electromagnetic field. The differential cross sections were investigated numerically for photon energies up to 50 MeV, external field intensity parameter $\nu^2$ to value 2, and all scattering angles. The variation of full cross sections with respect to external field intensity was also established. The presence of the external field led to resonances in the Compton scattering and pair production differential cross sections. These resonances were investigated by calculating the electron self energy in the presence of the external field. At resonance the differential cross sections were enhanced by several orders of magnitude. The resonances occurred for values of external field intensity parameter $\nu^2 <1$, lowering the limit of $\nu^2 \sim 1$ at which point non linear effects in first order external field QED processes become important. Generally, full cross sections increased with increasing external field intensity, though peaking sharply for Compton scattering and levelling off for pair production. An application was made to non linear background studies at $e^+e^-$ linear colliders. The pair production process and electron self energy were studied for the case of a constant crossed electromagnetic field. It was found that previous analytic expressions required the external field to be azimuthally symmetric. New analytic expressions for the more general non azimuthally symmetric case were developed and a numerical parameter range equivalent to that proposed for future linear collider designs was considered.
hep-ph/0505183
Joseph Schechter
S. Masood, S. Nasri and J. Schechter
Fine structure of beta decay endpoint spectrum
9 pages, 8 figures
Int.J.Mod.Phys. A21 (2006) 517-532
10.1142/S0217751X06028552
null
hep-ph
null
We note that the fine structure at the endpoint region of the beta decay spectrum is now essentially known using neutrino oscillation data, if the mass of one neutrino is specified. This may help to identify the effects of nonzero neutrino masses in future experiments. An exact treatment of phase space kinematics is used. This work is independent of theoretical models. Additional restrictions due to the assumption of a so-called "complementary ansatz" for the neutrino mass matrix are also discussed.
[ { "created": "Fri, 20 May 2005 19:13:37 GMT", "version": "v1" }, { "created": "Wed, 24 Aug 2005 21:36:42 GMT", "version": "v2" } ]
2009-11-11
[ [ "Masood", "S.", "" ], [ "Nasri", "S.", "" ], [ "Schechter", "J.", "" ] ]
We note that the fine structure at the endpoint region of the beta decay spectrum is now essentially known using neutrino oscillation data, if the mass of one neutrino is specified. This may help to identify the effects of nonzero neutrino masses in future experiments. An exact treatment of phase space kinematics is used. This work is independent of theoretical models. Additional restrictions due to the assumption of a so-called "complementary ansatz" for the neutrino mass matrix are also discussed.
1806.03522
Bowen Xiao
Bo-Wen Xiao and Feng Yuan
On the Threshold Resummation in Forward pA Collisions
11 pages, 1 figure
null
10.1016/j.physletb.2018.10.067
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, using the Higgs production in forward rapidity region in proton-nucleus collisions as an example, we demonstrate that we can construct a systematic formalism for the threshold resummation for forward rapidity particle productions in the saturation formalism. The forward threshold jet function, which satisfies the corresponding renormalization group equation, is introduced into the new factorization formula. This calculation can be easily generalized to other processes, such as single forward hadron productions at forward rapidity region, and have important phenomenological implications.
[ { "created": "Sat, 9 Jun 2018 18:21:22 GMT", "version": "v1" } ]
2018-11-28
[ [ "Xiao", "Bo-Wen", "" ], [ "Yuan", "Feng", "" ] ]
In this paper, using the Higgs production in forward rapidity region in proton-nucleus collisions as an example, we demonstrate that we can construct a systematic formalism for the threshold resummation for forward rapidity particle productions in the saturation formalism. The forward threshold jet function, which satisfies the corresponding renormalization group equation, is introduced into the new factorization formula. This calculation can be easily generalized to other processes, such as single forward hadron productions at forward rapidity region, and have important phenomenological implications.
hep-ph/9902294
Eugene Levin
E. Gotsman, E. Levin and U. Maor (Tel Aviv Un.)
The survival probability of large rapidity gaps in a three channel model
26 pages in latex file,11 figures in eps files
Phys.Rev.D60:094011,1999
10.1103/PhysRevD.60.094011
TAUP 2561 - 99
hep-ph
null
The values and energy dependence for the survival probability $< \mid S\mid^2 >$ of large rapidity gaps (LRG) are calculated in a three channel model. This model includes single and double diffractive production, as well as elastic rescattering. It is shown that $< \mid S \mid^2 >$ decreases with increasing energy, in line with recent results for LRG dijet production at the Tevatron. This is in spite of the weak dependence on energy of the ratio $ (\sigma_{el}+ \sigma_{SD})/\sigma_{tot}$.
[ { "created": "Wed, 10 Feb 1999 07:49:27 GMT", "version": "v1" } ]
2008-11-26
[ [ "Gotsman", "E.", "", "Tel Aviv Un." ], [ "Levin", "E.", "", "Tel Aviv Un." ], [ "Maor", "U.", "", "Tel Aviv Un." ] ]
The values and energy dependence for the survival probability $< \mid S\mid^2 >$ of large rapidity gaps (LRG) are calculated in a three channel model. This model includes single and double diffractive production, as well as elastic rescattering. It is shown that $< \mid S \mid^2 >$ decreases with increasing energy, in line with recent results for LRG dijet production at the Tevatron. This is in spite of the weak dependence on energy of the ratio $ (\sigma_{el}+ \sigma_{SD})/\sigma_{tot}$.
hep-ph/9609268
Kingman Cheung
Kingman Cheung, Wai-Yee Keung, and Tzu Chiang Yuan
Quarkonium Production At $Z^0$ and in $\Upsilon(1S)$ Decay
10 pages and three figures embedded using epsf.tex. Talk given at the UIC Quarkonium Workshop, Chicago IL, June 13-15 1996
Int.J.Mod.Phys.A12:3931-3940,1997
10.1142/S0217751X97002085
UTEXAS-HEP-96-13
hep-ph
null
The conventional color-singlet model was challenged by the recent data on quarkonium production. Discrepancies in production rates were observed at the Tevatron, at LEP, and in fixed-target experiments. The newly advocated color-octet mechanism provides a plausible solution to the anomalous quarkonium production observed at the Tevatron. The color-octet mechanism should also affect other quarkonium production channels. In this paper we will summarize the studies of quarkonium production in $Z^0$ and $\Upsilon$ decays.
[ { "created": "Thu, 5 Sep 1996 17:54:39 GMT", "version": "v1" } ]
2009-09-01
[ [ "Cheung", "Kingman", "" ], [ "Keung", "Wai-Yee", "" ], [ "Yuan", "Tzu Chiang", "" ] ]
The conventional color-singlet model was challenged by the recent data on quarkonium production. Discrepancies in production rates were observed at the Tevatron, at LEP, and in fixed-target experiments. The newly advocated color-octet mechanism provides a plausible solution to the anomalous quarkonium production observed at the Tevatron. The color-octet mechanism should also affect other quarkonium production channels. In this paper we will summarize the studies of quarkonium production in $Z^0$ and $\Upsilon$ decays.
1212.5709
Wei Chao
Wei Chao, Michael J. Ramsey-Musolf
Hidden from View: Neutrino Masses, Dark Matter and TeV-Scale Leptogenesis in a Neutrinophilic 2HDM
23 pages, 5 figures. Minor corrections, reference updated
Phys. Rev. D 89, 033007 (2014)
10.1103/PhysRevD.89.033007
NPAC-12-21
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a simple extension of the Standard Model providing dark matter and a TeV-scale seesaw mechanism that also allows for viable leptogenesis. In addition to the Standard Model degrees of freedom, the model contains a neutrinophilic Higgs doublet, a scalar singlet, and six singlet fermions (including three right-handed Majorana neutrinos) that are charged under a local $U(1)^\prime$ gauge symmetry. We show how the $U(1)^\prime$ charge assignments and the choice of scalar potential can lead to a TeV-scale seesaw mechanism and $\mathcal{O}(1)$ neutrino Yukawa couplings in a straightforward way. While this scenario has all the ingredients one would expect for significant experimental signatures, including several new TeV scale degrees of freedom, we find that most distinctive features associated with neutrino mass generation, leptogenesis and the dark sector are likely to remain inaccessible in the absence of additional lepton flavor symmetries.
[ { "created": "Sat, 22 Dec 2012 17:35:11 GMT", "version": "v1" }, { "created": "Tue, 2 Apr 2013 00:02:11 GMT", "version": "v2" } ]
2014-02-19
[ [ "Chao", "Wei", "" ], [ "Ramsey-Musolf", "Michael J.", "" ] ]
We consider a simple extension of the Standard Model providing dark matter and a TeV-scale seesaw mechanism that also allows for viable leptogenesis. In addition to the Standard Model degrees of freedom, the model contains a neutrinophilic Higgs doublet, a scalar singlet, and six singlet fermions (including three right-handed Majorana neutrinos) that are charged under a local $U(1)^\prime$ gauge symmetry. We show how the $U(1)^\prime$ charge assignments and the choice of scalar potential can lead to a TeV-scale seesaw mechanism and $\mathcal{O}(1)$ neutrino Yukawa couplings in a straightforward way. While this scenario has all the ingredients one would expect for significant experimental signatures, including several new TeV scale degrees of freedom, we find that most distinctive features associated with neutrino mass generation, leptogenesis and the dark sector are likely to remain inaccessible in the absence of additional lepton flavor symmetries.
1409.2372
Sacha Davidson
Assia Bessaa and Sacha Davidson
Estimated constraints on t-channel Leptoquark exchange from LHC contact interaction searches
8 pages,3 figures
null
10.1140/epjc/s10052-015-3313-0
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The t-channel exchange of a first generation leptoquark could contribute to the cross-section for q q-bar to e+e-. The leptoquark is off-shell, so this process can be sensitive to leptoquarks beyond the mass reach of pair production searches at the LHC (currently m_{LQ}> 830 GeV). We attempt to analytically translate ATLAS bounds on $ (\bar{q} \gamma ^\mu q) (\bar{e} \gamma _\mu e) $ contact interactions to the various scalar leptoquarks, and obtain a bound on their quark-lepton coupling of order $\lambda^2 \leq (m_{LQ}/2$ TeV)$^2$. The greatest difficulty in this translation is that the leptoquarks do not induce the contact interaction studied by ATLAS, so the interference with the Standard Model is different. If bounds were quoted on the functional dependance of the cross-section on s-hat, rather than on particular contact interaction models, this difficulty in applying experimental bounds to theoretical models could be circumvented.
[ { "created": "Mon, 8 Sep 2014 14:40:53 GMT", "version": "v1" } ]
2015-06-22
[ [ "Bessaa", "Assia", "" ], [ "Davidson", "Sacha", "" ] ]
The t-channel exchange of a first generation leptoquark could contribute to the cross-section for q q-bar to e+e-. The leptoquark is off-shell, so this process can be sensitive to leptoquarks beyond the mass reach of pair production searches at the LHC (currently m_{LQ}> 830 GeV). We attempt to analytically translate ATLAS bounds on $ (\bar{q} \gamma ^\mu q) (\bar{e} \gamma _\mu e) $ contact interactions to the various scalar leptoquarks, and obtain a bound on their quark-lepton coupling of order $\lambda^2 \leq (m_{LQ}/2$ TeV)$^2$. The greatest difficulty in this translation is that the leptoquarks do not induce the contact interaction studied by ATLAS, so the interference with the Standard Model is different. If bounds were quoted on the functional dependance of the cross-section on s-hat, rather than on particular contact interaction models, this difficulty in applying experimental bounds to theoretical models could be circumvented.
1202.0283
Hai-Bo Yu
Sean Tulin, Hai-Bo Yu, and Kathryn M. Zurek
Oscillating Asymmetric Dark Matter
23 pages, 4 figures, A typo fixed, References added
null
10.1088/1475-7516/2012/05/013
MCTP-12-03
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the dynamics of dark matter (DM) particle-antiparticle oscillations within the context of asymmetric DM. Oscillations arise due to small DM number-violating Majorana-type mass terms, and can lead to recoupling of annihilation after freeze-out and washout of the DM density. We derive the density matrix equations for DM oscillations and freeze-out from first principles using nonequilibrium field theory, and our results are qualitatively different than in previous studies. DM dynamics exhibits particle-vs-antiparticle "flavor" effects, depending on the interaction type, analogous to neutrino oscillations in a medium. "Flavor-sensitive" DM interactions include scattering or annihilation through a new vector boson, while "flavor-blind" interactions include scattering or s-channel annihilation through a new scalar boson, or annihilation to pairs of bosons. In particular, we find that flavor-sensitive annihilation does not recouple when coherent oscillations begin, and that flavor-blind scattering does not lead to decoherence.
[ { "created": "Wed, 1 Feb 2012 21:00:02 GMT", "version": "v1" }, { "created": "Mon, 13 Feb 2012 17:09:24 GMT", "version": "v2" } ]
2015-06-04
[ [ "Tulin", "Sean", "" ], [ "Yu", "Hai-Bo", "" ], [ "Zurek", "Kathryn M.", "" ] ]
We study the dynamics of dark matter (DM) particle-antiparticle oscillations within the context of asymmetric DM. Oscillations arise due to small DM number-violating Majorana-type mass terms, and can lead to recoupling of annihilation after freeze-out and washout of the DM density. We derive the density matrix equations for DM oscillations and freeze-out from first principles using nonequilibrium field theory, and our results are qualitatively different than in previous studies. DM dynamics exhibits particle-vs-antiparticle "flavor" effects, depending on the interaction type, analogous to neutrino oscillations in a medium. "Flavor-sensitive" DM interactions include scattering or annihilation through a new vector boson, while "flavor-blind" interactions include scattering or s-channel annihilation through a new scalar boson, or annihilation to pairs of bosons. In particular, we find that flavor-sensitive annihilation does not recouple when coherent oscillations begin, and that flavor-blind scattering does not lead to decoherence.
1011.1664
Roberto Auzzi
Roberto Auzzi and Amit Giveon
Superpartner spectrum of minimal gaugino-gauge mediation
8 pages, 3 figures; V2: refs and a few comments added; V3 title changed
JHEP 1101:003,2011
10.1007/JHEP01(2011)003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate the sparticle mass spectrum in the minimal four-dimensional construction that interpolates between gaugino and ordinary gauge mediation at the weak scale. We find that even in the hybrid case -- when the messenger scale is comparable to the mass of the additional gauge particles -- both the right-handed as well as the left-handed sleptons are lighter than the bino in the low-scale mediation regime. This implies a chain of lepton production and, consequently, striking signatures that may be probed at the LHC already in the near future.
[ { "created": "Sun, 7 Nov 2010 17:56:10 GMT", "version": "v1" }, { "created": "Sun, 14 Nov 2010 16:04:27 GMT", "version": "v2" }, { "created": "Mon, 27 Dec 2010 13:37:24 GMT", "version": "v3" } ]
2011-01-27
[ [ "Auzzi", "Roberto", "" ], [ "Giveon", "Amit", "" ] ]
We evaluate the sparticle mass spectrum in the minimal four-dimensional construction that interpolates between gaugino and ordinary gauge mediation at the weak scale. We find that even in the hybrid case -- when the messenger scale is comparable to the mass of the additional gauge particles -- both the right-handed as well as the left-handed sleptons are lighter than the bino in the low-scale mediation regime. This implies a chain of lepton production and, consequently, striking signatures that may be probed at the LHC already in the near future.
1912.09616
Bin Yang
Bin Yang, Bo Wang, Lu Meng, Shi-Lin Zhu
Isospin violating decay $D^*_s \to D_s \pi^0$ in chiral perturbation theory
8 pages,5 figures
Phys. Rev. D 101, 054019 (2020)
10.1103/PhysRevD.101.054019
null
hep-ph hep-ex hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We systematically calculate the isospin violating decay, $D_s^*\to D_s\pi^0$, with the heavy meson chiral perturbation theory up to $\mathcal{O}(p^3)$ including the loop diagrams. The $\mathcal{O}(p^3)$ tree level amplitudes contain four undetermined LECs. We use two strategies to estimate them. With the nonanalytic dominance approximation, we get $\Gamma[D_s^\ast\to D_s\pi^0]=(3.38\pm0.12)$ eV. With the naturalness assumption, we give a possible range of the isospin violating decay width, $[1.11-6.88]$ eV. We find that the contribution of the $\mathcal{O}(p^3)$ corrections might be significant.
[ { "created": "Fri, 20 Dec 2019 02:29:43 GMT", "version": "v1" } ]
2020-03-25
[ [ "Yang", "Bin", "" ], [ "Wang", "Bo", "" ], [ "Meng", "Lu", "" ], [ "Zhu", "Shi-Lin", "" ] ]
We systematically calculate the isospin violating decay, $D_s^*\to D_s\pi^0$, with the heavy meson chiral perturbation theory up to $\mathcal{O}(p^3)$ including the loop diagrams. The $\mathcal{O}(p^3)$ tree level amplitudes contain four undetermined LECs. We use two strategies to estimate them. With the nonanalytic dominance approximation, we get $\Gamma[D_s^\ast\to D_s\pi^0]=(3.38\pm0.12)$ eV. With the naturalness assumption, we give a possible range of the isospin violating decay width, $[1.11-6.88]$ eV. We find that the contribution of the $\mathcal{O}(p^3)$ corrections might be significant.
hep-ph/9907501
Guest Anyone
U. Aglietti (Rome1) and G. Ricciardi (Rome1)
Matching of the Shape Function
11 pages, 1 figure added, minor changes in the text
Phys.Lett.B466:313,1999
10.1016/S0370-2693(99)01103-X
preprint Roma1-1257-99
hep-ph
null
The shape function f(k_+) describes Fermi motion effects in inclusive semi-leptonic decays such as B -> X_u+e+nu near the end-point of the lepton spectrum. We compute the leading one-loop corrections to the shape function f(k_+) in the effective theory with a hard cut-off regularization. The matching constant onto full QCD is infrared safe, i.e. the leading infrared singularity represented by the term log^2(k_+) cancels in the difference of integrals. We compare the hard cut-off result with the result in dimensional regularization, the latter containing an additional factor of two in the coefficient of the log^2(k_+) term, and consequently requiring an oversubtraction.
[ { "created": "Mon, 26 Jul 1999 18:02:44 GMT", "version": "v1" }, { "created": "Thu, 29 Jul 1999 19:55:20 GMT", "version": "v2" }, { "created": "Tue, 21 Sep 1999 16:10:53 GMT", "version": "v3" } ]
2011-02-01
[ [ "Aglietti", "U.", "", "Rome1" ], [ "Ricciardi", "G.", "", "Rome1" ] ]
The shape function f(k_+) describes Fermi motion effects in inclusive semi-leptonic decays such as B -> X_u+e+nu near the end-point of the lepton spectrum. We compute the leading one-loop corrections to the shape function f(k_+) in the effective theory with a hard cut-off regularization. The matching constant onto full QCD is infrared safe, i.e. the leading infrared singularity represented by the term log^2(k_+) cancels in the difference of integrals. We compare the hard cut-off result with the result in dimensional regularization, the latter containing an additional factor of two in the coefficient of the log^2(k_+) term, and consequently requiring an oversubtraction.
2211.08359
Alessandro Strumia
Alessandro Strumia
Dark Matter from freeze-in and its inhomogeneities
8 pages. Published on JHEP
null
10.1007/JHEP03(2023)042
null
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
We consider generic freeze-in processes for generation of Dark Matter, together with the consequent re-thermalization of the Standard Model fluid. We find that Dark Matter inherits the Standard Model adiabatic inhomogeneities on the cosmological scales probed by current observations, that were super-horizon during freeze-in. Thereby, freeze-in satisfies the bounds on iso-curvature perturbations.
[ { "created": "Tue, 15 Nov 2022 18:07:01 GMT", "version": "v1" }, { "created": "Thu, 18 Jan 2024 10:48:12 GMT", "version": "v2" } ]
2024-01-19
[ [ "Strumia", "Alessandro", "" ] ]
We consider generic freeze-in processes for generation of Dark Matter, together with the consequent re-thermalization of the Standard Model fluid. We find that Dark Matter inherits the Standard Model adiabatic inhomogeneities on the cosmological scales probed by current observations, that were super-horizon during freeze-in. Thereby, freeze-in satisfies the bounds on iso-curvature perturbations.
hep-ph/9409285
null
K.S. Babu and S.M. Barr
Supersymmetric SO(10) Simplified
23 pages, BA-94-45
Phys.Rev.D51:2463-2470,1995
10.1103/PhysRevD.51.2463
null
hep-ph
null
In the context of supersymmetric $SO(10)$ grand unified models, it is shown that the gauge symmetry breaking as well as a natural doublet--triplet splitting can be achieved with a minimal Higgs system consisting of a single adjoint and a pair of vector and spinor multiplets. Such a Higgs spectrum has been shown to arise in the free fermionic formulation of superstrings. Since the symmetry breaking mechanism relies on non--renormalizable operators, some of the Higgs particles of the model turn out to have masses somewhat below the GUT scale. As a consequence, the unification scale is raised to about $2 \times 10^{17}~GeV$ and sin$^2\theta_W$ is predicted to be slightly larger than the minimal SUSY--$SU(5)$ value. Including threshold uncertainties, which turn out to be surprisingly small in the model, we show that sin$^2\theta_W$ prediction is consistent with experiments.
[ { "created": "Mon, 12 Sep 1994 20:36:12 GMT", "version": "v1" } ]
2011-05-12
[ [ "Babu", "K. S.", "" ], [ "Barr", "S. M.", "" ] ]
In the context of supersymmetric $SO(10)$ grand unified models, it is shown that the gauge symmetry breaking as well as a natural doublet--triplet splitting can be achieved with a minimal Higgs system consisting of a single adjoint and a pair of vector and spinor multiplets. Such a Higgs spectrum has been shown to arise in the free fermionic formulation of superstrings. Since the symmetry breaking mechanism relies on non--renormalizable operators, some of the Higgs particles of the model turn out to have masses somewhat below the GUT scale. As a consequence, the unification scale is raised to about $2 \times 10^{17}~GeV$ and sin$^2\theta_W$ is predicted to be slightly larger than the minimal SUSY--$SU(5)$ value. Including threshold uncertainties, which turn out to be surprisingly small in the model, we show that sin$^2\theta_W$ prediction is consistent with experiments.
1408.3013
Antonio Morais
D. J. Miller, A. P. Morais
Supersymmetric SO(10) Grand Unification at the LHC and Beyond
Published version
JHEP 1412 (2014) 132
10.1007/JHEP12(2014)132
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study models of supersymmetric grand unification based on the SO(10) gauge group. We investigate scenarios of non-universal gaugino masses including models containing a mixture of two representations of hidden sector chiral superfields. We analyse the effect of excluding mu from the fine-tuning measure, and confront the results with low energy constraints, including the Higgs boson mass, dark matter relic density and supersymmetry bounds. We also determine high scale Yukawa coupling ratios and confront the results with theoretical predictions. Finally, we present two additional benchmarks that should be explored at the LHC and future colliders.
[ { "created": "Wed, 13 Aug 2014 14:19:06 GMT", "version": "v1" }, { "created": "Tue, 19 Aug 2014 16:41:16 GMT", "version": "v2" }, { "created": "Sat, 27 Dec 2014 13:49:40 GMT", "version": "v3" } ]
2014-12-30
[ [ "Miller", "D. J.", "" ], [ "Morais", "A. P.", "" ] ]
We study models of supersymmetric grand unification based on the SO(10) gauge group. We investigate scenarios of non-universal gaugino masses including models containing a mixture of two representations of hidden sector chiral superfields. We analyse the effect of excluding mu from the fine-tuning measure, and confront the results with low energy constraints, including the Higgs boson mass, dark matter relic density and supersymmetry bounds. We also determine high scale Yukawa coupling ratios and confront the results with theoretical predictions. Finally, we present two additional benchmarks that should be explored at the LHC and future colliders.
hep-ph/9712217
Jose Luis Cortes
Jos\'e Luis Cort\'es, Jorge Gamboa and Luis Vel\'azquez
A Nambu-Jona-Lasinio like model from QCD at low energies
7 pages, Latex file, no figures, revised version to appear in Phys. Lett. B
Phys.Lett. B432 (1998) 397-401
10.1016/S0370-2693(98)00694-7
DFTUZ 97/26, USACH 97/11
hep-ph hep-th
null
A generalization to any dimension of the fermion field transformation which allows to derive the solution of the massless Schwinger model in the path integral framework is identified. New arguments based on this transformation for a Nambu-Jona-Lasinio (NJL) like model as the low energy limit of a gauge theory in dimension greater than two are presented. Our result supports the spontaneous chiral symmetry breaking picture conjectured by Nambu many years ago and the link between QCD, NJL and chiral models.
[ { "created": "Mon, 1 Dec 1997 16:37:21 GMT", "version": "v1" }, { "created": "Thu, 28 May 1998 09:34:15 GMT", "version": "v2" } ]
2009-10-30
[ [ "Cortés", "José Luis", "" ], [ "Gamboa", "Jorge", "" ], [ "Velázquez", "Luis", "" ] ]
A generalization to any dimension of the fermion field transformation which allows to derive the solution of the massless Schwinger model in the path integral framework is identified. New arguments based on this transformation for a Nambu-Jona-Lasinio (NJL) like model as the low energy limit of a gauge theory in dimension greater than two are presented. Our result supports the spontaneous chiral symmetry breaking picture conjectured by Nambu many years ago and the link between QCD, NJL and chiral models.
1011.3372
Wolfgang Lucha
Wolfgang Lucha, Dmitri Melikhov, Silvano Simula
Heavy-Quark Mass and Heavy-Meson Decay Constants from QCD Sum Rules
talk presented at "Quark Confinement and the Hadron Spectrum IX - QCHS IX" (30 August - 3 September 2010, Madrid, Spain), to appear in the proceedings; version 2: minor, purely cosmetic changes, 1 reference added
AIP Conf.Proc.1343:379-381,2011
10.1063/1.3575035
HEPHY-PUB 892/10
hep-ph hep-ex hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a sum-rule extraction of heavy-meson decay constants from the two-point correlator of heavy-light pseudoscalar currents. Our main concern is to control the uncertainties of the decay constants, induced by both input QCD parameters and limited accuracy of the sum-rule method. Gaining this control is possible by applying our novel procedure for the extraction of hadron observables utilizing Borel-parameter-depending dual thresholds. For the charmed mesons, we obtain f_D = 206.2 \pm 7.3 (OPE) \pm 5.1 (syst) MeV and f_{D_s} = 245.3 \pm 15.7 (OPE) \pm 4.5 (syst) MeV. For the beauty mesons, the decay constants prove to be extremely sensitive to the exact value of the b-quark MS-bar mass m_b(m_b). Matching our sum-rule prediction for f_B to the lattice findings, the very accurate b-mass value m_b(m_b) = 4.245 \pm 0.025 GeV is found, which yields f_B = 193.4 \pm 12.3 (OPE) \pm 4.3 (syst) MeV and f_{B_s} = 232.5 \pm 18.6 (OPE) \pm 2.4 (syst) MeV.
[ { "created": "Mon, 15 Nov 2010 13:14:37 GMT", "version": "v1" }, { "created": "Sat, 4 Dec 2010 16:56:11 GMT", "version": "v2" } ]
2011-06-15
[ [ "Lucha", "Wolfgang", "" ], [ "Melikhov", "Dmitri", "" ], [ "Simula", "Silvano", "" ] ]
We present a sum-rule extraction of heavy-meson decay constants from the two-point correlator of heavy-light pseudoscalar currents. Our main concern is to control the uncertainties of the decay constants, induced by both input QCD parameters and limited accuracy of the sum-rule method. Gaining this control is possible by applying our novel procedure for the extraction of hadron observables utilizing Borel-parameter-depending dual thresholds. For the charmed mesons, we obtain f_D = 206.2 \pm 7.3 (OPE) \pm 5.1 (syst) MeV and f_{D_s} = 245.3 \pm 15.7 (OPE) \pm 4.5 (syst) MeV. For the beauty mesons, the decay constants prove to be extremely sensitive to the exact value of the b-quark MS-bar mass m_b(m_b). Matching our sum-rule prediction for f_B to the lattice findings, the very accurate b-mass value m_b(m_b) = 4.245 \pm 0.025 GeV is found, which yields f_B = 193.4 \pm 12.3 (OPE) \pm 4.3 (syst) MeV and f_{B_s} = 232.5 \pm 18.6 (OPE) \pm 2.4 (syst) MeV.
0803.1989
Ruth Britto
Ruth Britto, Bo Feng, Pierpaolo Mastrolia
Closed-Form Decomposition of One-Loop Massive Amplitudes
37 pages
Phys.Rev.D78:025031,2008
10.1103/PhysRevD.78.025031
CERN-PH-TH/2008-050
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present formulas for the coefficients of 2-, 3-, 4- and 5-point master integrals for one-loop massive amplitudes. The coefficients are derived from unitarity cuts in D dimensions. The input parameters can be read off from any unitarity-cut integrand, as assembled from tree-level expressions, after simple algebraic manipulations. The formulas presented here are suitable for analytical as well as numerical evaluation. Their validity is confirmed in two known cases of helicity amplitudes contributing to gg -> gg and gg -> gH, where the masses of the Higgs and the fermion circulating in the loop are kept as free parameters.
[ { "created": "Thu, 13 Mar 2008 15:18:53 GMT", "version": "v1" } ]
2008-11-26
[ [ "Britto", "Ruth", "" ], [ "Feng", "Bo", "" ], [ "Mastrolia", "Pierpaolo", "" ] ]
We present formulas for the coefficients of 2-, 3-, 4- and 5-point master integrals for one-loop massive amplitudes. The coefficients are derived from unitarity cuts in D dimensions. The input parameters can be read off from any unitarity-cut integrand, as assembled from tree-level expressions, after simple algebraic manipulations. The formulas presented here are suitable for analytical as well as numerical evaluation. Their validity is confirmed in two known cases of helicity amplitudes contributing to gg -> gg and gg -> gH, where the masses of the Higgs and the fermion circulating in the loop are kept as free parameters.
hep-ph/0603219
Katsuji Yamamoto
Katsuichi Higuchi, Masato Senami, and Katsuji Yamamoto
Universality of strength for Yukawa couplings with extra down-type quark singlets
Only the title is shortened, accepted for Phys. Lett. B, 10 pages, 1. figure
Phys.Lett. B638 (2006) 492-496
10.1016/j.physletb.2006.06.002
null
hep-ph
null
We investigate the quark masses and mixings by including vector-like down-type quark singlets in universality of strength for Yukawa couplings (USY). In contrast with the standard model with USY, the sufficient $ CP $ violation is obtained for the Cabibbo-Kobayashi-Maskawa matrix through the mixing between the ordinary quarks and quark singlets. The top-bottom mass hierarchy $ m_t \gg m_b $ also appears naturally in the USY scheme with the down-type quark singlets.
[ { "created": "Mon, 27 Mar 2006 03:09:10 GMT", "version": "v1" }, { "created": "Mon, 5 Jun 2006 03:07:08 GMT", "version": "v2" } ]
2009-11-11
[ [ "Higuchi", "Katsuichi", "" ], [ "Senami", "Masato", "" ], [ "Yamamoto", "Katsuji", "" ] ]
We investigate the quark masses and mixings by including vector-like down-type quark singlets in universality of strength for Yukawa couplings (USY). In contrast with the standard model with USY, the sufficient $ CP $ violation is obtained for the Cabibbo-Kobayashi-Maskawa matrix through the mixing between the ordinary quarks and quark singlets. The top-bottom mass hierarchy $ m_t \gg m_b $ also appears naturally in the USY scheme with the down-type quark singlets.
hep-ph/0301019
Mustafa Savci
T. M. Aliev, A. Ozpineci, M. Savci
Explicit expressions of the 'Lambda' baryon polarizations in (Lambda_b -> Lambda l^+ l^-) decay for the massive lepton case
2 pages, LaTeX formatted
null
null
metu-phys-hep-02-36
hep-ph
null
We present the explicit form of the expressions of the 'Lambda' baryon polarizations in (Lambda_b -> Lambda l^+ l^-) decay for the massive lepton case as a complementary to our previous work prep: hep--ph/0211447.
[ { "created": "Sun, 5 Jan 2003 14:58:16 GMT", "version": "v1" } ]
2007-05-23
[ [ "Aliev", "T. M.", "" ], [ "Ozpineci", "A.", "" ], [ "Savci", "M.", "" ] ]
We present the explicit form of the expressions of the 'Lambda' baryon polarizations in (Lambda_b -> Lambda l^+ l^-) decay for the massive lepton case as a complementary to our previous work prep: hep--ph/0211447.
1509.03848
Ning Chen
Ning Chen, Jinmian Li, Yandong Liu
LHC searches for heavy neutral Higgs bosons with a top jet substructure analysis
21 pages, 5 figures; v2: matches the published version
Phys. Rev. D 93, 095013 (2016)
10.1103/PhysRevD.93.095013
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the LHC searches for the heavy $CP$-odd Higgs boson $A$ and $CP$-even Higgs boson $H$ in the context of general two-Higgs-doublet model. Specifically, we consider the decay mode of $A/H\to t \bar t $ through the $b \bar b$ or $t \bar t $ associated production channels. In the so-called "alignment limit" of the two-Higgs-doublet model, this decay mode can be the most dominant one. By employing the HEPTopTagger and the multi-variable-analysis method, we present the search sensitivities for both $CP$-odd Higgs boson $A$ and $CP$-even Higgs boson $H$ via these channels at the high-luminosity LHC runs.
[ { "created": "Sun, 13 Sep 2015 13:54:50 GMT", "version": "v1" }, { "created": "Sun, 15 May 2016 15:41:28 GMT", "version": "v2" } ]
2016-05-25
[ [ "Chen", "Ning", "" ], [ "Li", "Jinmian", "" ], [ "Liu", "Yandong", "" ] ]
We study the LHC searches for the heavy $CP$-odd Higgs boson $A$ and $CP$-even Higgs boson $H$ in the context of general two-Higgs-doublet model. Specifically, we consider the decay mode of $A/H\to t \bar t $ through the $b \bar b$ or $t \bar t $ associated production channels. In the so-called "alignment limit" of the two-Higgs-doublet model, this decay mode can be the most dominant one. By employing the HEPTopTagger and the multi-variable-analysis method, we present the search sensitivities for both $CP$-odd Higgs boson $A$ and $CP$-even Higgs boson $H$ via these channels at the high-luminosity LHC runs.
hep-ph/9406307
Owe Philipsen
O.Philipsen
On the problem of the magnetic mass
4pp., 2figs, uuencoded ps-file; Contribution to the NATO Advanced Research workshop 'Electroweak Physics and the Early Universe', 23-25 March 1994, Sintra, Portugal
null
null
null
hep-ph
null
The dynamical generation of a transverse gauge field mass is studied by means of gap equations for pure gauge theory and the gauged non-linear sigma model in three dimensions. Non-trivial solutions to the gap equations are found indicating that this type of mass generation is a feature of the static sector of finite temperature field theory. In the case of the non-linear sigma model the transverse mass can be defined in a manifestly gauge invariant manner. Its value is determined to be m=0.28g^2.
[ { "created": "Tue, 14 Jun 1994 15:57:21 GMT", "version": "v1" } ]
2007-05-23
[ [ "Philipsen", "O.", "" ] ]
The dynamical generation of a transverse gauge field mass is studied by means of gap equations for pure gauge theory and the gauged non-linear sigma model in three dimensions. Non-trivial solutions to the gap equations are found indicating that this type of mass generation is a feature of the static sector of finite temperature field theory. In the case of the non-linear sigma model the transverse mass can be defined in a manifestly gauge invariant manner. Its value is determined to be m=0.28g^2.
hep-ph/0103240
Ian G. Moss
Ian G Moss, Noriko Shiiki and Takashi Torii
Vacuum energy of CP(1) solitons
16 pages, 6 figures
null
null
null
hep-ph
null
The vacuum energy of two CP(1) solitons on a torus is computed numerically. A numerical technique for zeta-function regularisation is proposed to remove the divergences of the vacuum energy. After performing the numerical regularisation, we observe the effect of the vacuum energy on the two soliton interactions.
[ { "created": "Thu, 22 Mar 2001 14:07:35 GMT", "version": "v1" } ]
2007-05-23
[ [ "Moss", "Ian G", "" ], [ "Shiiki", "Noriko", "" ], [ "Torii", "Takashi", "" ] ]
The vacuum energy of two CP(1) solitons on a torus is computed numerically. A numerical technique for zeta-function regularisation is proposed to remove the divergences of the vacuum energy. After performing the numerical regularisation, we observe the effect of the vacuum energy on the two soliton interactions.
2307.06321
Henri H\"anninen
G. Beuf, H. H\"anninen, T. Lappi, H. M\"antysaari, Y. Mulian
Diffractive Deep Inelastic Scattering in the Dipole Picture at Next-to-Leading Order
DIS2023, talk by HH; 5 pages, 3 figures
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the contribution from the $q \bar q g$ state production to the diffractive cross sections in deep inelastic scattering at high energy. The obtained cross section is finite by itself, and consists a part of the full next-to-leading order result for the diffractive structure functions. Our calculation for the diffractive structure functions is performed using exact kinematics, under the shockwave approximation of the scattering process. Once the calculation is completed, we show that the previously known behaviour at the high-$Q^2$ and large-$M_X^2$ regime can be extracted from our results by taking the appropriate limits. Furthermore, we discuss the steps required to obtain the complete next-to-leading order results for the structure functions in the color glass condensate (CGC) formalism, and the application of these results to phenomenology.
[ { "created": "Wed, 12 Jul 2023 17:33:16 GMT", "version": "v1" } ]
2023-07-13
[ [ "Beuf", "G.", "" ], [ "Hänninen", "H.", "" ], [ "Lappi", "T.", "" ], [ "Mäntysaari", "H.", "" ], [ "Mulian", "Y.", "" ] ]
We calculate the contribution from the $q \bar q g$ state production to the diffractive cross sections in deep inelastic scattering at high energy. The obtained cross section is finite by itself, and consists a part of the full next-to-leading order result for the diffractive structure functions. Our calculation for the diffractive structure functions is performed using exact kinematics, under the shockwave approximation of the scattering process. Once the calculation is completed, we show that the previously known behaviour at the high-$Q^2$ and large-$M_X^2$ regime can be extracted from our results by taking the appropriate limits. Furthermore, we discuss the steps required to obtain the complete next-to-leading order results for the structure functions in the color glass condensate (CGC) formalism, and the application of these results to phenomenology.
1104.2192
Marina Nielsen
R.M. Albuquerque and M. Nielsen
Erratum: QCD sum rules study of the $J^{PC}=1^{--}$ charmonium $Y$ mesons
1 page
Nucl.Phys.A815:53-66,2009; Erratum-ibid.A857:48-49,2011
10.1016/j.nuclphysa.2008.10.015 10.1016/j.nuclphysa.2011.04.001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We correct a mistake in the analytical expression given in Nucl. Phys. {\bf A} 815, 53 (2009) [arXiv:0804.4817] for the $D_{s0}\bar{D}_s^*$ and $D_{0}\bar{D}^*$ molecular currents. As a consequence, the mass obtained for the $D_{0}\bar{D}^*$ molecular current: $m_{D_{0}\bar{D}^*}=(4.96\pm 0.11)$ GeV is no longer compatible with the experimental mass of the meson Y(4260).
[ { "created": "Tue, 12 Apr 2011 12:38:27 GMT", "version": "v1" } ]
2011-04-28
[ [ "Albuquerque", "R. M.", "" ], [ "Nielsen", "M.", "" ] ]
We correct a mistake in the analytical expression given in Nucl. Phys. {\bf A} 815, 53 (2009) [arXiv:0804.4817] for the $D_{s0}\bar{D}_s^*$ and $D_{0}\bar{D}^*$ molecular currents. As a consequence, the mass obtained for the $D_{0}\bar{D}^*$ molecular current: $m_{D_{0}\bar{D}^*}=(4.96\pm 0.11)$ GeV is no longer compatible with the experimental mass of the meson Y(4260).
1804.02519
Kazem Azizi
S. S. Agaev, K. Azizi, H. Sundu
The nonet of the light scalar tetraquarks: the mesons $a_0(980)$ and $K_{0}^{\ast }(800)$
10 Pages and 4 Figures
null
null
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The spectroscopic parameters and partial decay widths of the light mesons $ a_0(980) $ and $K_{0}^{\ast}(800)$ are calculated by treating them as scalar diquark-antidiquark states. The masses and couplings of the mesons are found in the framework of QCD two-point sum rule approach. The widths of the decay channels $a_0(980) \to \eta \pi$ and $a_0(980) \to K \bar{K}$, and $ K_{0}^{\ast}(800) \to K^{+} \pi^{-}$ and $K_{0}^{\ast}(800) \to K^{0} \pi^{0} $ are evaluated using QCD sum rules on the light-cone and technical tools of the soft meson approximation. Our results for the mass of the mesons $m_{a_0}=991^{+29}_{-27} \ \mathrm{MeV}$ and $m_{K^{ \ast}}=767^{+38}_{-29} \ \mathrm{MeV}$, as well as their total width $\Gamma _{\mathrm{a_0}}=62.01\pm 14.37\ \mathrm{MeV}$ and $\Gamma _{\mathrm{ K_0^{\ast}}}=401.1\pm 87.1\ \mathrm{MeV}$ are compared with last experimental data.
[ { "created": "Sat, 7 Apr 2018 07:22:44 GMT", "version": "v1" }, { "created": "Sat, 12 May 2018 08:03:04 GMT", "version": "v2" }, { "created": "Fri, 4 Jan 2019 07:42:11 GMT", "version": "v3" } ]
2019-01-07
[ [ "Agaev", "S. S.", "" ], [ "Azizi", "K.", "" ], [ "Sundu", "H.", "" ] ]
The spectroscopic parameters and partial decay widths of the light mesons $ a_0(980) $ and $K_{0}^{\ast}(800)$ are calculated by treating them as scalar diquark-antidiquark states. The masses and couplings of the mesons are found in the framework of QCD two-point sum rule approach. The widths of the decay channels $a_0(980) \to \eta \pi$ and $a_0(980) \to K \bar{K}$, and $ K_{0}^{\ast}(800) \to K^{+} \pi^{-}$ and $K_{0}^{\ast}(800) \to K^{0} \pi^{0} $ are evaluated using QCD sum rules on the light-cone and technical tools of the soft meson approximation. Our results for the mass of the mesons $m_{a_0}=991^{+29}_{-27} \ \mathrm{MeV}$ and $m_{K^{ \ast}}=767^{+38}_{-29} \ \mathrm{MeV}$, as well as their total width $\Gamma _{\mathrm{a_0}}=62.01\pm 14.37\ \mathrm{MeV}$ and $\Gamma _{\mathrm{ K_0^{\ast}}}=401.1\pm 87.1\ \mathrm{MeV}$ are compared with last experimental data.
hep-ph/9403305
null
R. Casalbuoni, P. Chiappetta, A. Deandrea, S. De Curtis, D. Dominici and R. Gatto
Pseudo Goldstones at Future Colliders from the Extended Bess Model
17 pages and 12 figures (included as a uuencoded tar file), LaTeX (style article), UGVA-DPT 1994/03-845
Z.Phys. C65 (1995) 327-336
10.1007/BF01571890
null
hep-ph
null
We consider the production of the lightest pseudo-Goldstone bosons at future colliders through the vector resonances predicted by the extended BESS model, which consists of an effective lagrangian parametrization with dynamical symmetry breaking, describing scalar, vector and axial-vector bound states in a rather general framework. We find that the detection of pseudo-Goldstone pairs at LHC requires a careful evaluation of backgrounds. For e+e- collisions in the TeV range the backgrounds can be easily reduced and the detection of pseudo-Goldstone pairs is generally easier.
[ { "created": "Thu, 17 Mar 1994 19:45:00 GMT", "version": "v1" } ]
2009-10-28
[ [ "Casalbuoni", "R.", "" ], [ "Chiappetta", "P.", "" ], [ "Deandrea", "A.", "" ], [ "De Curtis", "S.", "" ], [ "Dominici", "D.", "" ], [ "Gatto", "R.", "" ] ]
We consider the production of the lightest pseudo-Goldstone bosons at future colliders through the vector resonances predicted by the extended BESS model, which consists of an effective lagrangian parametrization with dynamical symmetry breaking, describing scalar, vector and axial-vector bound states in a rather general framework. We find that the detection of pseudo-Goldstone pairs at LHC requires a careful evaluation of backgrounds. For e+e- collisions in the TeV range the backgrounds can be easily reduced and the detection of pseudo-Goldstone pairs is generally easier.
2206.01453
Liaofu Luo
Liaofu Luo and Jun Lv
Application of Generalized Quaternion in Physics
21 pages
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The applications of quaternion in physics are discussed with an emphasis on elementary particle symmetry and interaction. Three colours of the quark and the quantum chromodynamics (QCD) can be introduced directly from the invariance of basic equations under the quaternion phase transformation (quaternion gauge invariance). The generalized quaternions obey the SU(3) symmetry. QCD is essentially the quantum quaternion dynamics. The further generalization of SU(3) quaternion to G2 octonion is worked out. We demonstrate that the G2 octonion contains seven tri-generator sets of SU(2) symmetry and three of them form SU(3) subgroup. A model of the elementary particle classification and interaction based on octonion gauge theory is proposed. The model unifies the colour and flavour of all particles. It provides a framework for the unified description of four kinds of elementary particles (quarks, leptons, gauge fields and Higgs bosons) and their interactions.
[ { "created": "Fri, 3 Jun 2022 08:36:20 GMT", "version": "v1" }, { "created": "Tue, 29 Nov 2022 03:41:52 GMT", "version": "v2" } ]
2022-11-30
[ [ "Luo", "Liaofu", "" ], [ "Lv", "Jun", "" ] ]
The applications of quaternion in physics are discussed with an emphasis on elementary particle symmetry and interaction. Three colours of the quark and the quantum chromodynamics (QCD) can be introduced directly from the invariance of basic equations under the quaternion phase transformation (quaternion gauge invariance). The generalized quaternions obey the SU(3) symmetry. QCD is essentially the quantum quaternion dynamics. The further generalization of SU(3) quaternion to G2 octonion is worked out. We demonstrate that the G2 octonion contains seven tri-generator sets of SU(2) symmetry and three of them form SU(3) subgroup. A model of the elementary particle classification and interaction based on octonion gauge theory is proposed. The model unifies the colour and flavour of all particles. It provides a framework for the unified description of four kinds of elementary particles (quarks, leptons, gauge fields and Higgs bosons) and their interactions.
1805.07334
Hiroyuki Nishiura
Yoshio Koide and Hiroyuki Nishiura
Parameter-Independent Quark Mass Relation in the U(3)$\times$U(3)$'$ Model
12 pages, 4 figures, accepted version by MPLA
null
10.1142/S0217732318502309
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, we have proposed a quark mass matrix model based on U(3)$\times$U(3)$'$ family symmetry, in which up- and down-quark mass matrices $M_u$ and $M_d$ are described only by complex parameters $a_u $ and $a_d $, respectively. When we use charged lepton masses as additional input values, we can successfully obtain predictions for quark masses and Cabibbo-Kobayashi-Maskawa mixing. Since we have only one complex parameter $a_q$ for each mass matrix $M_q$, we can obtain a parameter-independent mass relation by using three equations for ${\rm Tr}[H_q]$, ${\rm Tr}[H_q H_q]$ and ${\rm det}H_q$, where $H_q \equiv M_q M_q^\dagger$ ($q=u, d$). In this paper, we investigate its parameter-independent feature of the quark mass relation in the model.
[ { "created": "Fri, 18 May 2018 17:30:47 GMT", "version": "v1" }, { "created": "Sat, 6 Oct 2018 12:45:16 GMT", "version": "v2" } ]
2019-01-30
[ [ "Koide", "Yoshio", "" ], [ "Nishiura", "Hiroyuki", "" ] ]
Recently, we have proposed a quark mass matrix model based on U(3)$\times$U(3)$'$ family symmetry, in which up- and down-quark mass matrices $M_u$ and $M_d$ are described only by complex parameters $a_u $ and $a_d $, respectively. When we use charged lepton masses as additional input values, we can successfully obtain predictions for quark masses and Cabibbo-Kobayashi-Maskawa mixing. Since we have only one complex parameter $a_q$ for each mass matrix $M_q$, we can obtain a parameter-independent mass relation by using three equations for ${\rm Tr}[H_q]$, ${\rm Tr}[H_q H_q]$ and ${\rm det}H_q$, where $H_q \equiv M_q M_q^\dagger$ ($q=u, d$). In this paper, we investigate its parameter-independent feature of the quark mass relation in the model.
hep-ph/0410157
Paul Sutcliffe
Richard Battye and Paul Sutcliffe
Skyrmions and the pion mass
17 pages, including 8 figures. Version to appear in Nucl.Phys.B
Nucl.Phys. B705 (2005) 384-400
10.1016/j.nuclphysb.2004.11.018
null
hep-ph hep-th
null
We present numerical evidence that suggests the introduction of a non-zero pion mass might dramatically affect the structure of minimal energy Skyrmions. It appears that the shell-like Skyrmions which are the minima when the pions are massless can fail to be minimal energy bound states for particular baryon numbers, with a strong dependence upon the value of the pion mass. The effects of a pion mass may include the replacement of shell-like configurations with crystal chunks and the loss of shell-like bound states with baryon numbers five and eight; which is in agreement with expectations based on real nuclei.
[ { "created": "Mon, 11 Oct 2004 23:02:45 GMT", "version": "v1" }, { "created": "Mon, 1 Nov 2004 16:27:50 GMT", "version": "v2" } ]
2010-04-05
[ [ "Battye", "Richard", "" ], [ "Sutcliffe", "Paul", "" ] ]
We present numerical evidence that suggests the introduction of a non-zero pion mass might dramatically affect the structure of minimal energy Skyrmions. It appears that the shell-like Skyrmions which are the minima when the pions are massless can fail to be minimal energy bound states for particular baryon numbers, with a strong dependence upon the value of the pion mass. The effects of a pion mass may include the replacement of shell-like configurations with crystal chunks and the loss of shell-like bound states with baryon numbers five and eight; which is in agreement with expectations based on real nuclei.
1010.5637
Guido Altarelli
Guido Altarelli
Particle Physics at the LHC Start
17 pages. From talks given at the 22nd Rencontres de Blois on Particle Physics and Cosmology, Blois, France, July 15-20, 2010, at the Symposium on High Energy Strong Interactions, Kyoto, Japan, August 9 -13, 2010 and at the LHC days in Split, Split, Croatia, October 4-9, 2010
Prog.Theor.Phys.Suppl.187:305-321,2011
10.1143/PTPS.187.305
RM3-TH/10-10, CERN-PH-TH/2010-249
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I present a concise review of the major issues and challenges in particle physics at the start of the LHC era. After a brief overview of the Standard Model and of QCD, I will focus on the electroweak symmetry breaking problem which plays a central role in particle physics today. The Higgs sector of the minimal Standard Model is so far just a mere conjecture that needs to be verified or discarded by the LHC. Probably the reality is more complicated. I will summarize the motivation for new physics that should accompany or even replace the Higgs discovery and a number of its possible forms that could be revealed by the LHC.
[ { "created": "Wed, 27 Oct 2010 10:17:47 GMT", "version": "v1" } ]
2011-05-27
[ [ "Altarelli", "Guido", "" ] ]
I present a concise review of the major issues and challenges in particle physics at the start of the LHC era. After a brief overview of the Standard Model and of QCD, I will focus on the electroweak symmetry breaking problem which plays a central role in particle physics today. The Higgs sector of the minimal Standard Model is so far just a mere conjecture that needs to be verified or discarded by the LHC. Probably the reality is more complicated. I will summarize the motivation for new physics that should accompany or even replace the Higgs discovery and a number of its possible forms that could be revealed by the LHC.
hep-ph/0102261
V. Gogohia
V. Gogohia
A gauge invariant formulation of intrinsically nonperturbative QCD
26 pages including one Table, some new material and clarifications are introduced, typos corrected as well as a few new references are added
null
null
null
hep-ph
null
Using a system of the corresponding Schwinger-Dyson equations of motion, a pure dynamical theory of quark confinement and spontaneous breakdown of chiral symmetry is formulated. It is based on dominated in the QCD vacuum self-interaction of massless gluons only, i.e., without involving some extra degrees of freedom. This interaction becomes strongly singular in the deep infrared domain leading thus to the enhancement of zero momentum modes in the nonperturbative QCD vacuum. Using theory of distributions, complemented by the dimensional regularization method, we have explicitly shown that strong infrared singularities can be put under control. In this way a new phase in QCD, intrinsically nonperturbative QCD which is manifestly gauge invariant, was discovered. As a result, a highly nontrivial dynamical and topological structure of the QCD vacuum has emerged within our approach. We have also explicitly shown how infrared multiplicative renormalization program should be done in order to self-consistently remove all the strong infrared singularities from the theory. The corresponding convergence conditions play a crucial role in this program. In this theory any physical observables are determined by such correlation functions from which all types of the perturbative contributions should be subtracted, by definition. Theory is not only infrared finite but it is free from the ultraviolet divergences as well. It has a mass gap $\Delta > 0$, i.e., there are no physical states in the interval $(0, \Delta)$. It explains confinement, spontaneous breakdown of chiral symmetry and other nonperturbative effects on a general ground and in self-consistent way.
[ { "created": "Wed, 21 Feb 2001 12:13:30 GMT", "version": "v1" }, { "created": "Thu, 19 Apr 2001 12:44:04 GMT", "version": "v2" }, { "created": "Fri, 1 Jun 2001 13:23:27 GMT", "version": "v3" } ]
2007-05-23
[ [ "Gogohia", "V.", "" ] ]
Using a system of the corresponding Schwinger-Dyson equations of motion, a pure dynamical theory of quark confinement and spontaneous breakdown of chiral symmetry is formulated. It is based on dominated in the QCD vacuum self-interaction of massless gluons only, i.e., without involving some extra degrees of freedom. This interaction becomes strongly singular in the deep infrared domain leading thus to the enhancement of zero momentum modes in the nonperturbative QCD vacuum. Using theory of distributions, complemented by the dimensional regularization method, we have explicitly shown that strong infrared singularities can be put under control. In this way a new phase in QCD, intrinsically nonperturbative QCD which is manifestly gauge invariant, was discovered. As a result, a highly nontrivial dynamical and topological structure of the QCD vacuum has emerged within our approach. We have also explicitly shown how infrared multiplicative renormalization program should be done in order to self-consistently remove all the strong infrared singularities from the theory. The corresponding convergence conditions play a crucial role in this program. In this theory any physical observables are determined by such correlation functions from which all types of the perturbative contributions should be subtracted, by definition. Theory is not only infrared finite but it is free from the ultraviolet divergences as well. It has a mass gap $\Delta > 0$, i.e., there are no physical states in the interval $(0, \Delta)$. It explains confinement, spontaneous breakdown of chiral symmetry and other nonperturbative effects on a general ground and in self-consistent way.
hep-ph/0310182
Ayres Freitas
A. Freitas, A. von Manteuffel, P. M. Zerwas
Slepton Production at e+e- and e-e- Linear Colliders
50 pp, uses amsmath.sty, version to appear in EPJ C. Manuscript with higher resolution figures available at http://theory.fnal.gov/people/afreitas/
Eur.Phys.J. C34 (2004) 487-512
10.1140/epjc/s2004-01744-2
DESY 03-111, FERMILAB-Pub-03/314-T
hep-ph hep-ex
null
High-precision analyses are presented for the production of scalar sleptons, selectrons and smuons in supersymmetric theories, at future e+e- and e-e- linear colliders. Threshold production can be exploited for measurements of the selectron and smuon masses, an essential ingredient for the reconstruction of the fundamental supersymmetric theory at high scales. The production of selectrons in the continuum will allow us to determine the Yukawa couplings in the selectron sector, scrutinizing the identity of the Yukawa and gauge couplings, which is a basic consequence of supersymmetry. The theoretical predictions are elaborated at the one-loop level in the continuum, while at threshold non-zero width effects and Sommerfeld rescattering corrections are included. The phenomenological analyses are performed for e+e- and e-e- linear colliders with energy up to about 1 TeV and with high integrated luminosity up to 1 ab^-1 to cover the individual slepton channels separately with high precision.
[ { "created": "Wed, 15 Oct 2003 15:46:25 GMT", "version": "v1" }, { "created": "Wed, 10 Mar 2004 20:24:23 GMT", "version": "v2" } ]
2007-05-23
[ [ "Freitas", "A.", "" ], [ "von Manteuffel", "A.", "" ], [ "Zerwas", "P. M.", "" ] ]
High-precision analyses are presented for the production of scalar sleptons, selectrons and smuons in supersymmetric theories, at future e+e- and e-e- linear colliders. Threshold production can be exploited for measurements of the selectron and smuon masses, an essential ingredient for the reconstruction of the fundamental supersymmetric theory at high scales. The production of selectrons in the continuum will allow us to determine the Yukawa couplings in the selectron sector, scrutinizing the identity of the Yukawa and gauge couplings, which is a basic consequence of supersymmetry. The theoretical predictions are elaborated at the one-loop level in the continuum, while at threshold non-zero width effects and Sommerfeld rescattering corrections are included. The phenomenological analyses are performed for e+e- and e-e- linear colliders with energy up to about 1 TeV and with high integrated luminosity up to 1 ab^-1 to cover the individual slepton channels separately with high precision.
2312.11291
Matthias Wei{\ss}wange
Dominik St\"ockinger and Matthias Wei{\ss}wange
Full three-loop Renormalisation of an abelian chiral Gauge Theory with non-anticommuting $\gamma_5$ in the BMHV Scheme
null
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this work we present a complete three-loop renormalisation of an abelian chiral gauge theory within the Breitenlohner-Maison/'t Hooft-Veltman (BMHV) scheme of dimensional regularisation (DReg). In this scheme the $\gamma_5$-matrix appearing in gauge interactions is a non-anticommuting object, leading to a breaking of gauge and BRST invariance. Employing an efficient method based on the quantum action principle, we obtain the complete three-loop counterterm action which serves both to render the theory finite and to restore gauge and BRST invariance. The UV singular counterterms involve not only higher order $\epsilon$-poles but also new counterterm structures emerging at the three-loop level for the first time; the finite symmetry-restoring counterterms are restricted to the same structures as at lower loop orders, just with different coefficients, aligning with our expectations. Both the singular and the finite counterterms include structures which cannot be obtained by the standard multiplicative renormalisation. Our results demonstrate that a rigorous treatment of chiral gauge theories with $\gamma_5$ defined in the BMHV scheme at the multi-loop level is possible and that the obtained counterterm action is suitable for computer implementations, allowing automated calculations without ambiguities caused by $\gamma_5$.
[ { "created": "Mon, 18 Dec 2023 15:34:27 GMT", "version": "v1" } ]
2023-12-19
[ [ "Stöckinger", "Dominik", "" ], [ "Weißwange", "Matthias", "" ] ]
In this work we present a complete three-loop renormalisation of an abelian chiral gauge theory within the Breitenlohner-Maison/'t Hooft-Veltman (BMHV) scheme of dimensional regularisation (DReg). In this scheme the $\gamma_5$-matrix appearing in gauge interactions is a non-anticommuting object, leading to a breaking of gauge and BRST invariance. Employing an efficient method based on the quantum action principle, we obtain the complete three-loop counterterm action which serves both to render the theory finite and to restore gauge and BRST invariance. The UV singular counterterms involve not only higher order $\epsilon$-poles but also new counterterm structures emerging at the three-loop level for the first time; the finite symmetry-restoring counterterms are restricted to the same structures as at lower loop orders, just with different coefficients, aligning with our expectations. Both the singular and the finite counterterms include structures which cannot be obtained by the standard multiplicative renormalisation. Our results demonstrate that a rigorous treatment of chiral gauge theories with $\gamma_5$ defined in the BMHV scheme at the multi-loop level is possible and that the obtained counterterm action is suitable for computer implementations, allowing automated calculations without ambiguities caused by $\gamma_5$.
1906.11306
Thomas Schaefer
Mauricio Martinez, Thomas Schaefer, Vladimir Skokov
Critical behavior of the bulk viscosity in QCD
18 pages, 3 figures; version to appear in PRD
Phys. Rev. D 100, 074017 (2019)
10.1103/PhysRevD.100.074017
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the behavior of the bulk viscosity $\zeta$ in QCD near a possible critical endpoint in the phase diagram. We verify the expectation that $(\zeta/s)\sim a(\xi/\xi_0)^{x_\zeta}$, where $s$ is the entropy density, $\xi$ is the correlation length, $\xi_0$ is the non-critical correlation length, $a$ is a constant and $x_\zeta\simeq 3$. Using a recently developed equation of state that includes a critical point in the universality class of the Ising model we estimate the constant of proportionality $a$. We find that $a$ is typically quite small, $a\sim O(10^{-4})$. We observe, however, that the result is sensitive to the commonly made assumption that the Ising temperature axis is approximately aligned with the QCD baryon chemical potential axis. If this is not the case, then the critical $\zeta/s$ can approach the non-critical value of $\eta/s$, where $\eta$ is the shear viscosity, even if the enhancement of the correlation length is modest, $\xi/\xi_0\sim 2$.
[ { "created": "Wed, 26 Jun 2019 19:34:35 GMT", "version": "v1" }, { "created": "Fri, 11 Oct 2019 17:21:38 GMT", "version": "v2" } ]
2019-10-23
[ [ "Martinez", "Mauricio", "" ], [ "Schaefer", "Thomas", "" ], [ "Skokov", "Vladimir", "" ] ]
We study the behavior of the bulk viscosity $\zeta$ in QCD near a possible critical endpoint in the phase diagram. We verify the expectation that $(\zeta/s)\sim a(\xi/\xi_0)^{x_\zeta}$, where $s$ is the entropy density, $\xi$ is the correlation length, $\xi_0$ is the non-critical correlation length, $a$ is a constant and $x_\zeta\simeq 3$. Using a recently developed equation of state that includes a critical point in the universality class of the Ising model we estimate the constant of proportionality $a$. We find that $a$ is typically quite small, $a\sim O(10^{-4})$. We observe, however, that the result is sensitive to the commonly made assumption that the Ising temperature axis is approximately aligned with the QCD baryon chemical potential axis. If this is not the case, then the critical $\zeta/s$ can approach the non-critical value of $\eta/s$, where $\eta$ is the shear viscosity, even if the enhancement of the correlation length is modest, $\xi/\xi_0\sim 2$.
2406.07643
Subhojit Roy
Waleed Abdallah, Raj Gandhi, Tathgata Ghosh, Najimuddin Khan, Samiran Roy, and Subhojit Roy
A 17 MeV pseudoscalar and the LSND, MiniBooNE and ATOMKI anomalies
39 pages, 6 figures and 3 tables
null
null
HRI-RECAPP-2024-02
hep-ph hep-ex
http://creativecommons.org/publicdomain/zero/1.0/
In the absence of any new physics signals at the Large Hadron Collider (LHC), anomalous results at low energy experiments have become the subject of increased attention and scrutiny. We focus on three such results from the LSND, MiniBooNE (MB), and ATOMKI experiments. A 17 MeV pseudoscalar mediator ($a'$) can account for the excess events seen in $^8$Be and $^4$He pair creation transitions in ATOMKI. We incorporate this mediator in a gauge invariant extension of the Standard Model (SM) with a second Higgs doublet and three singlet (seesaw) neutrinos ($N_i, i=1,2,3$). $N_{1,2}$ participate in an interaction in MB and LSND which, with $a'$ as mediator, leads to the production of $e^+ e^-$ pairs. The $N_i$ also lead to mass-squared differences for SM neutrinos in agreement with global oscillation data. We first show that such a model offers a clean and natural joint solution to the MB and LSND excesses. We then examine the possibility of a common solution to all three anomalies. Using the values of the couplings to the quarks and electrons which are required to explain pair creation nuclear transition data for $^8$Be and $^4$He in ATOMKI, we show that these values lead to excellent fits for MB and LSND data as well, allowing for a common solution. We obtain a representative solution space for this, in the context of an important constraint that comes from the decay $K^+ \rightarrow \pi^+ a' \, (a'\rightarrow e^+e^-$). We also discuss other constraints on the model from both collider and non-collider experiments as well as those from electroweak precision data, stability and unitarity. We compute the contributions to the electron and muon $g-2$ up to two loops for our model and discuss the results in the context of the current theoretical and empirical scenario vis a vis these parameters. Finally, we discuss future tests of the model in upcoming experiments.
[ { "created": "Tue, 11 Jun 2024 18:17:02 GMT", "version": "v1" } ]
2024-06-13
[ [ "Abdallah", "Waleed", "" ], [ "Gandhi", "Raj", "" ], [ "Ghosh", "Tathgata", "" ], [ "Khan", "Najimuddin", "" ], [ "Roy", "Samiran", "" ], [ "Roy", "Subhojit", "" ] ]
In the absence of any new physics signals at the Large Hadron Collider (LHC), anomalous results at low energy experiments have become the subject of increased attention and scrutiny. We focus on three such results from the LSND, MiniBooNE (MB), and ATOMKI experiments. A 17 MeV pseudoscalar mediator ($a'$) can account for the excess events seen in $^8$Be and $^4$He pair creation transitions in ATOMKI. We incorporate this mediator in a gauge invariant extension of the Standard Model (SM) with a second Higgs doublet and three singlet (seesaw) neutrinos ($N_i, i=1,2,3$). $N_{1,2}$ participate in an interaction in MB and LSND which, with $a'$ as mediator, leads to the production of $e^+ e^-$ pairs. The $N_i$ also lead to mass-squared differences for SM neutrinos in agreement with global oscillation data. We first show that such a model offers a clean and natural joint solution to the MB and LSND excesses. We then examine the possibility of a common solution to all three anomalies. Using the values of the couplings to the quarks and electrons which are required to explain pair creation nuclear transition data for $^8$Be and $^4$He in ATOMKI, we show that these values lead to excellent fits for MB and LSND data as well, allowing for a common solution. We obtain a representative solution space for this, in the context of an important constraint that comes from the decay $K^+ \rightarrow \pi^+ a' \, (a'\rightarrow e^+e^-$). We also discuss other constraints on the model from both collider and non-collider experiments as well as those from electroweak precision data, stability and unitarity. We compute the contributions to the electron and muon $g-2$ up to two loops for our model and discuss the results in the context of the current theoretical and empirical scenario vis a vis these parameters. Finally, we discuss future tests of the model in upcoming experiments.
2403.02099
Wei He
Wei He, De-Shun Zhang, Zhi-Feng Sun
The $Z_b$ states as the mixture of the molecular and diquark-anti-diquark components within the effective field theory
9 pages, 2 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this study, we reconsider the states $Z_b(10610)$ and $Z_b(10650)$ by investigating the presence of diquark-anti-diquark components as well as the hadronic molecule components in the framework of effective field theory. The different masses of pseudoscalar mesons such as $\pi^{0}$, $\eta_{8}$, and $\eta_{0}$, as well as vector mesons like $\rho^{0}$ and $\omega$ violate the OZI rule that is well depicted under the $[U(3)_L\otimes U(3)_R]_{global}\otimes [U(3)_V]_{local}$ symmetry. To account for the contribution of intermediate bosons of heavy masses within the OBE model, we introduce an exponential form factor instead of the commonly used monopole form factor in the past. By solving the coupled-channel Schr\"{o}dinger equation with the Gaussian expansion method, our numerical results indicate that the $Z_b(10610)$ and $Z_b(10650)$ states can be explained as hadronic molecules slightly mixing with diquark-anti-diquark states.
[ { "created": "Mon, 4 Mar 2024 14:56:16 GMT", "version": "v1" }, { "created": "Tue, 26 Mar 2024 06:19:36 GMT", "version": "v2" } ]
2024-03-27
[ [ "He", "Wei", "" ], [ "Zhang", "De-Shun", "" ], [ "Sun", "Zhi-Feng", "" ] ]
In this study, we reconsider the states $Z_b(10610)$ and $Z_b(10650)$ by investigating the presence of diquark-anti-diquark components as well as the hadronic molecule components in the framework of effective field theory. The different masses of pseudoscalar mesons such as $\pi^{0}$, $\eta_{8}$, and $\eta_{0}$, as well as vector mesons like $\rho^{0}$ and $\omega$ violate the OZI rule that is well depicted under the $[U(3)_L\otimes U(3)_R]_{global}\otimes [U(3)_V]_{local}$ symmetry. To account for the contribution of intermediate bosons of heavy masses within the OBE model, we introduce an exponential form factor instead of the commonly used monopole form factor in the past. By solving the coupled-channel Schr\"{o}dinger equation with the Gaussian expansion method, our numerical results indicate that the $Z_b(10610)$ and $Z_b(10650)$ states can be explained as hadronic molecules slightly mixing with diquark-anti-diquark states.
hep-ph/0306064
Tom Steele
V. Elias, D.G.C. McKeon, T.G. Steele
Transmutation of Scale Dependence into Truncation Uncertainty via RG-Improvement of the $R(s)$ Series
11 pages, LateX
Phys.Rev. D69 (2004) 045015
10.1103/PhysRevD.69.045015
null
hep-ph
null
The arbitrariness in how the logarithm is defined within the QCD series for the inclusive electroproduction cross-section is shown to affect the summation to all orders in $\alpha_s$ of leading and successively-subleading logarithms within that perturbative series, even though such summations largely eliminate the residual dependence of the original series on the arbitrary renormalization scale $\mu$. However, given that the original (unimproved) series is known to third-order in $\alpha_s(\mu)$, this logarithm ambiguity is shown not to enter the optimally improved summation-of-logarithms series until the term fourth-order in $\alpha_s(s)$, where $s$ is the physical center-of-mass energy squared. Consequently, the ambiguity in how the logarithm is defined is absorbable in the uncertainty associated with truncating the original perturbative series after its calculationally known terms.
[ { "created": "Fri, 6 Jun 2003 23:07:48 GMT", "version": "v1" }, { "created": "Tue, 9 Dec 2003 18:31:24 GMT", "version": "v2" } ]
2009-11-10
[ [ "Elias", "V.", "" ], [ "McKeon", "D. G. C.", "" ], [ "Steele", "T. G.", "" ] ]
The arbitrariness in how the logarithm is defined within the QCD series for the inclusive electroproduction cross-section is shown to affect the summation to all orders in $\alpha_s$ of leading and successively-subleading logarithms within that perturbative series, even though such summations largely eliminate the residual dependence of the original series on the arbitrary renormalization scale $\mu$. However, given that the original (unimproved) series is known to third-order in $\alpha_s(\mu)$, this logarithm ambiguity is shown not to enter the optimally improved summation-of-logarithms series until the term fourth-order in $\alpha_s(s)$, where $s$ is the physical center-of-mass energy squared. Consequently, the ambiguity in how the logarithm is defined is absorbable in the uncertainty associated with truncating the original perturbative series after its calculationally known terms.
hep-ph/0312025
David London
Veronique Page and David London
CP Violation in B -> rho pi: New Physics Signals
8 pages, 1 figure (included), plain LaTeX. Analysis modified: QCD factorization used instead of naive factorization; larger |P/T| range taken; figure changed; other minor changes; references updated. To be published in PRD: Brief Reports
Phys.Rev. D70 (2004) 017501
10.1103/PhysRevD.70.017501
UdeM-GPP-TH-03-116, McGill/03-27
hep-ph
null
A Dalitz-plot analysis of Bd(t) -> rho pi -> pi+ pi- pi0 decays allows one to obtain the CP-violating phase \alpha. In addition, one can extract the various tree (T) and penguin (P) amplitudes contributing to these decays. By comparing the measured value of |P/T| with the theoretical prediction, one can detect the presence of physics beyond the standard model.
[ { "created": "Tue, 2 Dec 2003 03:26:28 GMT", "version": "v1" }, { "created": "Sat, 12 Jun 2004 12:10:41 GMT", "version": "v2" } ]
2009-11-10
[ [ "Page", "Veronique", "" ], [ "London", "David", "" ] ]
A Dalitz-plot analysis of Bd(t) -> rho pi -> pi+ pi- pi0 decays allows one to obtain the CP-violating phase \alpha. In addition, one can extract the various tree (T) and penguin (P) amplitudes contributing to these decays. By comparing the measured value of |P/T| with the theoretical prediction, one can detect the presence of physics beyond the standard model.
hep-ph/9612424
Ann Heinson
A.P. Heinson (UC Riverside), A.S. Belyaev and E.E. Boos (Moscow State University)
Single top quarks at the Fermilab Tevatron
31 pages including 11 figures
Phys.Rev.D56:3114-3128,1997
10.1103/PhysRevD.56.3114
INP-MSU-96-41/448, UCR/96-25
hep-ph
null
We present a calculation of the single top quark cross section for proton-antiproton interactions with sqrt(s) = 1.8 TeV at the Fermilab Tevatron collider. We examine the effects of top mass, parton distribution functions, QCD scale, and collision energy, on each of the component production mechanisms, and study the kinematic distributions for standard model electroweak production. At the upgraded Tevatron with sqrt(s) = 2.0 TeV and high luminosity, it will be possible to test the nature of the Wtb coupling using single top production. We estimate the sensitivity to measure the single top cross section, and thus to directly measure V_tb and the top quark partial width. We show what happens to the V_tb measurement when an anomalous (V+A) component is added to the Wtb coupling, and how the top quark polarization affects the kinematic distributions.
[ { "created": "Thu, 19 Dec 1996 23:14:10 GMT", "version": "v1" } ]
2009-02-18
[ [ "Heinson", "A. P.", "", "UC Riverside" ], [ "Belyaev", "A. S.", "", "Moscow State\n University" ], [ "Boos", "E. E.", "", "Moscow State\n University" ] ]
We present a calculation of the single top quark cross section for proton-antiproton interactions with sqrt(s) = 1.8 TeV at the Fermilab Tevatron collider. We examine the effects of top mass, parton distribution functions, QCD scale, and collision energy, on each of the component production mechanisms, and study the kinematic distributions for standard model electroweak production. At the upgraded Tevatron with sqrt(s) = 2.0 TeV and high luminosity, it will be possible to test the nature of the Wtb coupling using single top production. We estimate the sensitivity to measure the single top cross section, and thus to directly measure V_tb and the top quark partial width. We show what happens to the V_tb measurement when an anomalous (V+A) component is added to the Wtb coupling, and how the top quark polarization affects the kinematic distributions.
2111.12635
Igor Anikin
I.V. Anikin, L. Szymanowski
Alignment function as a new kind of transverse momentum dependent functions
13 pages, 1 Figure; altered version: explanations and clarifications added
null
10.1140/epja/s10050-022-00794-8
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We argue the existence of new $k_\perp$-dependent functions which can be manifested in the Drell-Yan (SIDIS)-like processes. The presented new functions resemble the well-known Boer-Mulders function associated with the quark spin asymmetry, but in contrast they are sensitive to the transverse motion of partons inside the hadron due to the collective alignment of quark spin vectors.
[ { "created": "Wed, 24 Nov 2021 17:13:41 GMT", "version": "v1" }, { "created": "Thu, 2 Dec 2021 17:26:11 GMT", "version": "v2" }, { "created": "Tue, 15 Feb 2022 15:21:10 GMT", "version": "v3" } ]
2022-09-14
[ [ "Anikin", "I. V.", "" ], [ "Szymanowski", "L.", "" ] ]
We argue the existence of new $k_\perp$-dependent functions which can be manifested in the Drell-Yan (SIDIS)-like processes. The presented new functions resemble the well-known Boer-Mulders function associated with the quark spin asymmetry, but in contrast they are sensitive to the transverse motion of partons inside the hadron due to the collective alignment of quark spin vectors.
hep-ph/0009121
Armin Boehrer
A. Boehrer
Heavy Quark Production in $\gamma\gamma$ Collisions
3 pages, Talk given at the ICHEP'2000, Osaka, To appear in the proceedings
null
null
SI-2000-8
hep-ph
null
New results on inclusive heavy quark production in gamma gamma collisions are presented. Charm and bottom production are investigated at LEP II energies by the experiments ALEPH, DELPHI, L3, and OPAL. The total and differential cross sections for charm quarks are measured. The contributions from the direct and single-resolved processes are separated and their fractions quantified. More detailed studies, such as the dependence of the cross section on the two-photon centre-of-mass energy and the charm structure function F^2_gamma,c, are reported. The inclusive bottom cross section is presented. Measurements are compared to next-to-leading order calculations.
[ { "created": "Mon, 11 Sep 2000 14:58:36 GMT", "version": "v1" } ]
2007-05-23
[ [ "Boehrer", "A.", "" ] ]
New results on inclusive heavy quark production in gamma gamma collisions are presented. Charm and bottom production are investigated at LEP II energies by the experiments ALEPH, DELPHI, L3, and OPAL. The total and differential cross sections for charm quarks are measured. The contributions from the direct and single-resolved processes are separated and their fractions quantified. More detailed studies, such as the dependence of the cross section on the two-photon centre-of-mass energy and the charm structure function F^2_gamma,c, are reported. The inclusive bottom cross section is presented. Measurements are compared to next-to-leading order calculations.
2003.10631
Zhi-Gang Wang
Zhi-Gang Wang
Analysis of the tetraquark and hexaquark molecular states with the QCD sum rules
22 pages, 18 figures. arXiv admin note: text overlap with arXiv:2002.06202
Commun. Theor. Phys. 73 (2021) 065201
10.1088/1572-9494/abee0d
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this article, we construct the color-singlet-color-singlet type currents and the color-singlet-color-singlet-color-singlet type currents to study the scalar $D^*\bar{D}^*$, $D^*D^*$ tetraquark molecular states and the vector $D^*D^*\bar{D}^*$, $D^*D^*D^*$ hexaquark molecular states with the QCD sum rules in details. In calculations, we choose the pertinent energy scales of the QCD spectral densities with the energy scale formula $\mu=\sqrt{M^2_{T}-(2{\mathbb{M}}_c)^2}$ and $\sqrt{M^2_{H}-(3{\mathbb{M}}_c)^2}$ for the tetraquark and hexaquark molecular states respectively in a consistent way. We obtain stable QCD sum rules for the scalar $D^*\bar{D}^*$, $D^*D^*$ tetraquark molecular states and the vector $D^*D^*\bar{D}^*$ hexaquark molecular state, but cannot obtain stable QCD sum rules for the vector $D^*D^*D^*$ hexaquark molecular state. The connected (nonfactorizable) Feynman diagrams at the tree level (or the lowest order) and their induced diagrams via substituting the quark lines make positive contributions for the scalar $D^*D^*$ tetraquark molecular state, but make negative or destructive contributions for the vector $D^*D^*D^*$ hexaquark molecular state. It is of no use or meaningless to distinguish the factorizable and nonfactorizable properties of the Feynman diagrams in the color space in the operator product expansion so as to interpret them in terms of the hadronic observables, we can only obtain information about the short-distance and long-distance contributions.
[ { "created": "Tue, 24 Mar 2020 03:01:14 GMT", "version": "v1" }, { "created": "Mon, 24 Aug 2020 03:27:15 GMT", "version": "v2" }, { "created": "Tue, 23 Feb 2021 08:13:31 GMT", "version": "v3" } ]
2021-04-13
[ [ "Wang", "Zhi-Gang", "" ] ]
In this article, we construct the color-singlet-color-singlet type currents and the color-singlet-color-singlet-color-singlet type currents to study the scalar $D^*\bar{D}^*$, $D^*D^*$ tetraquark molecular states and the vector $D^*D^*\bar{D}^*$, $D^*D^*D^*$ hexaquark molecular states with the QCD sum rules in details. In calculations, we choose the pertinent energy scales of the QCD spectral densities with the energy scale formula $\mu=\sqrt{M^2_{T}-(2{\mathbb{M}}_c)^2}$ and $\sqrt{M^2_{H}-(3{\mathbb{M}}_c)^2}$ for the tetraquark and hexaquark molecular states respectively in a consistent way. We obtain stable QCD sum rules for the scalar $D^*\bar{D}^*$, $D^*D^*$ tetraquark molecular states and the vector $D^*D^*\bar{D}^*$ hexaquark molecular state, but cannot obtain stable QCD sum rules for the vector $D^*D^*D^*$ hexaquark molecular state. The connected (nonfactorizable) Feynman diagrams at the tree level (or the lowest order) and their induced diagrams via substituting the quark lines make positive contributions for the scalar $D^*D^*$ tetraquark molecular state, but make negative or destructive contributions for the vector $D^*D^*D^*$ hexaquark molecular state. It is of no use or meaningless to distinguish the factorizable and nonfactorizable properties of the Feynman diagrams in the color space in the operator product expansion so as to interpret them in terms of the hadronic observables, we can only obtain information about the short-distance and long-distance contributions.
1103.2334
Emerson Luna
E.G.S. Luna
Diffraction phenomenology with massive gluons: some recent developments
Invited keynote talk at Diffractive and Electromagnetic Processes at the LHC, Trento, Italy, January 2010; invited talk at XI Hadron Physics, Maresias, Brazil, March 2010
AIP Conf.Proc.1296:183-188,2010
10.1063/1.3523165
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this talk we introduce the main features of a QCD-based model in which the coupling $\alpha_{s}$ is constrained by an infrared mass scale. We show recent applications of this model to hadron-hadron collisions, gap survival probability calculations, and soft gluon resummation techniques. These results indicate a smooth transition from non-perturbative to perturbative behaviour of the QCD.
[ { "created": "Fri, 11 Mar 2011 18:34:03 GMT", "version": "v1" } ]
2011-05-12
[ [ "Luna", "E. G. S.", "" ] ]
In this talk we introduce the main features of a QCD-based model in which the coupling $\alpha_{s}$ is constrained by an infrared mass scale. We show recent applications of this model to hadron-hadron collisions, gap survival probability calculations, and soft gluon resummation techniques. These results indicate a smooth transition from non-perturbative to perturbative behaviour of the QCD.
2305.19325
Pablo Sesma
Raffaele Tito D'Agnolo, Florian Nortier, Gabriele Rigo, Pablo Sesma
The Two Scales of New Physics in Higgs Couplings
41 pages + references, 14 figures. v2: JHEP version
JHEP 08 (2023) 019
10.1007/JHEP08(2023)019
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Higgs coupling deviations from Standard Model predictions contain information about two scales of Nature: that of new physics responsible for the deviation, and the scale where new bosons must appear. The two can coincide, but they do not have to. The scale of new bosons can be calculated by going beyond an effective field theory description of the coupling deviation. We compute model-independent upper bounds on the scale of new bosons for deviations in Higgs to $WW$ and $ZZ$ couplings, finding that any measured deviation at present or future colliders requires the existence of new bosons within experimental reach. This has potentially interesting implications for naturalness.
[ { "created": "Tue, 30 May 2023 18:00:06 GMT", "version": "v1" }, { "created": "Thu, 10 Aug 2023 09:23:30 GMT", "version": "v2" } ]
2023-08-11
[ [ "D'Agnolo", "Raffaele Tito", "" ], [ "Nortier", "Florian", "" ], [ "Rigo", "Gabriele", "" ], [ "Sesma", "Pablo", "" ] ]
Higgs coupling deviations from Standard Model predictions contain information about two scales of Nature: that of new physics responsible for the deviation, and the scale where new bosons must appear. The two can coincide, but they do not have to. The scale of new bosons can be calculated by going beyond an effective field theory description of the coupling deviation. We compute model-independent upper bounds on the scale of new bosons for deviations in Higgs to $WW$ and $ZZ$ couplings, finding that any measured deviation at present or future colliders requires the existence of new bosons within experimental reach. This has potentially interesting implications for naturalness.
1602.02380
Evgeny Zhemchugov
S. I. Godunov, A. N. Rozanov, M. I. Vysotsky, E. V. Zhemchugov
New Physics at 1 TeV?
7 pages, 4 figures, 1 table
null
10.1134/S0021364016090101
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If decays of a heavy particle S are responsible for the diphoton excess with invariant mass 750 GeV observed at the 13 TeV LHC run, it can be easily accomodated in the Standard Model. Two scenarios are considered: production in gluon fusion through a loop of heavy isosinglet quark(s) and production in photon fusion through a loop of heavy isosinglet leptons. In the second case many heavy leptons are needed or/and they should have large electric charges in order to reproduce experimental data on $\sigma(pp \to SX) \cdot \mathrm{Br}(S \to \gamma \gamma)$.
[ { "created": "Sun, 7 Feb 2016 15:21:39 GMT", "version": "v1" } ]
2016-08-24
[ [ "Godunov", "S. I.", "" ], [ "Rozanov", "A. N.", "" ], [ "Vysotsky", "M. I.", "" ], [ "Zhemchugov", "E. V.", "" ] ]
If decays of a heavy particle S are responsible for the diphoton excess with invariant mass 750 GeV observed at the 13 TeV LHC run, it can be easily accomodated in the Standard Model. Two scenarios are considered: production in gluon fusion through a loop of heavy isosinglet quark(s) and production in photon fusion through a loop of heavy isosinglet leptons. In the second case many heavy leptons are needed or/and they should have large electric charges in order to reproduce experimental data on $\sigma(pp \to SX) \cdot \mathrm{Br}(S \to \gamma \gamma)$.
hep-ph/0105009
Krishna Rajagopal
Mark Alford (Glasgow University), Krishna Rajagopal (MIT), Sanjay Reddy (INT, University of Washington), Frank Wilczek (MIT)
The Minimal CFL-Nuclear Interface
30 pages, 7 figures
Phys.Rev. D64 (2001) 074017
10.1103/PhysRevD.64.074017
GUTPA/01/04/03, MIT-CTP-3123, DOE/ER/41132-110-INT01
hep-ph astro-ph nucl-th
null
At nuclear matter density, electrically neutral strongly interacting matter in weak equilibrium is made of neutrons, protons and electrons. At sufficiently high density, such matter is made of up, down and strange quarks in the color-flavor locked phase, with no electrons. As a function of increasing density (or, perhaps, increasing depth in a compact star) other phases may intervene between these two phases which are guaranteed to be present. The simplest possibility, however, is a single first order phase transition between CFL and nuclear matter. Such a transition, in space, could take place either through a mixed phase region or at a single sharp interface with electron-free CFL and electron-rich nuclear matter in stable contact. Here we construct a model for such an interface. It is characterized by a region of separated charge, similar to an inversion layer at a metal-insulator boundary. On the CFL side, the charged boundary layer is dominated by a condensate of negative kaons. We then consider the energetics of the mixed phase alternative. We find that the mixed phase will occur only if the nuclear-CFL surface tension is significantly smaller than dimensional analysis would indicate.
[ { "created": "Tue, 1 May 2001 22:52:35 GMT", "version": "v1" } ]
2009-11-07
[ [ "Alford", "Mark", "", "Glasgow University" ], [ "Rajagopal", "Krishna", "", "MIT" ], [ "Reddy", "Sanjay", "", "INT, University of Washington" ], [ "Wilczek", "Frank", "", "MIT" ] ]
At nuclear matter density, electrically neutral strongly interacting matter in weak equilibrium is made of neutrons, protons and electrons. At sufficiently high density, such matter is made of up, down and strange quarks in the color-flavor locked phase, with no electrons. As a function of increasing density (or, perhaps, increasing depth in a compact star) other phases may intervene between these two phases which are guaranteed to be present. The simplest possibility, however, is a single first order phase transition between CFL and nuclear matter. Such a transition, in space, could take place either through a mixed phase region or at a single sharp interface with electron-free CFL and electron-rich nuclear matter in stable contact. Here we construct a model for such an interface. It is characterized by a region of separated charge, similar to an inversion layer at a metal-insulator boundary. On the CFL side, the charged boundary layer is dominated by a condensate of negative kaons. We then consider the energetics of the mixed phase alternative. We find that the mixed phase will occur only if the nuclear-CFL surface tension is significantly smaller than dimensional analysis would indicate.
1211.4850
Jay Tasson
Jay D. Tasson
Lorentz violation, gravitomagnetism, and intrinsic spin
5 pages, accepted for publication in Phys. Rev. D
Phys. Rev. D 86, 124021 (2012)
10.1103/PhysRevD.86.124021
null
hep-ph gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A largely unconstrained set of relativity-violating effects is studied via the gravitomagnetic effect on intrinsic spins. The results of existing comagnetometer experiments are used to place constraints on two new combinations of these effects at the 10% level. We show that planned improvements in these experiments will make them competitive with the best existing sensitivities to this elusive class of relativity-violating effects. Prospects for measuring the conventional General-Relativistic gravitomagnetic effect are also considered.
[ { "created": "Tue, 20 Nov 2012 20:17:36 GMT", "version": "v1" } ]
2013-08-07
[ [ "Tasson", "Jay D.", "" ] ]
A largely unconstrained set of relativity-violating effects is studied via the gravitomagnetic effect on intrinsic spins. The results of existing comagnetometer experiments are used to place constraints on two new combinations of these effects at the 10% level. We show that planned improvements in these experiments will make them competitive with the best existing sensitivities to this elusive class of relativity-violating effects. Prospects for measuring the conventional General-Relativistic gravitomagnetic effect are also considered.
1311.2347
Yuji Kajiyama
Yuji Kajiyama, Akari Sato, Wakako Sato and Aya Suzuki
One-parameter Neutrino Mass Matrix and Symmetry Realization
14pages, 4figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the Majorana neutrino mass matrix $M_{\nu}$ with one parameter in the context of two texture zeros and its symmetry realization by non-Abelian discrete symmetry. From numerical calculation, we confirm that the textures $(M_{\nu})_{11,12}=0$ and $(M_{\nu})_{11,13}=0$ are consistent with the current experimental constraints, and show the correlations between non-zero elements of $M_{\nu}$. The ratios of non-zero elements of $M_{\nu}$ are constrain in small regions, and we find simple examples of $M_{\nu}$ with one real mass parameter. We also discuss symmetry realization of the mass matrix by the type-II seesaw mechanism based on the binary icosahedral symmetry $A_5'$ .
[ { "created": "Mon, 11 Nov 2013 04:09:55 GMT", "version": "v1" } ]
2013-11-12
[ [ "Kajiyama", "Yuji", "" ], [ "Sato", "Akari", "" ], [ "Sato", "Wakako", "" ], [ "Suzuki", "Aya", "" ] ]
We investigate the Majorana neutrino mass matrix $M_{\nu}$ with one parameter in the context of two texture zeros and its symmetry realization by non-Abelian discrete symmetry. From numerical calculation, we confirm that the textures $(M_{\nu})_{11,12}=0$ and $(M_{\nu})_{11,13}=0$ are consistent with the current experimental constraints, and show the correlations between non-zero elements of $M_{\nu}$. The ratios of non-zero elements of $M_{\nu}$ are constrain in small regions, and we find simple examples of $M_{\nu}$ with one real mass parameter. We also discuss symmetry realization of the mass matrix by the type-II seesaw mechanism based on the binary icosahedral symmetry $A_5'$ .
1111.4968
Haitham Zaraket H.
Alaa Dbeyssi, Dima Al Dirani and H. Zaraket
Synchrotron radiation in a chromo-magnetic field
Accepted for publication in Phys. Rev. D
null
10.1103/PhysRevD.84.105033
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the generalization of QED synchrotron radiation to the QCD case with a chromomagnetic field using the Schwinger {\it et al} source method. It is shown that the QED case can be obtained as a special limit. The comparison with the path integral approach of Zakharov has shown consistent results.
[ { "created": "Mon, 21 Nov 2011 18:40:11 GMT", "version": "v1" } ]
2015-06-03
[ [ "Dbeyssi", "Alaa", "" ], [ "Dirani", "Dima Al", "" ], [ "Zaraket", "H.", "" ] ]
We study the generalization of QED synchrotron radiation to the QCD case with a chromomagnetic field using the Schwinger {\it et al} source method. It is shown that the QED case can be obtained as a special limit. The comparison with the path integral approach of Zakharov has shown consistent results.
hep-ph/0505261
Michael Strickland
Anton Rebhan, Paul Romatschke, and Michael Strickland
Dynamics of Quark-Gluon-Plasma Instabilities in Discretized Hard-Loop Approximation
30 pages, 16 figures. v3 typos fixed
JHEP0509:041,2005
10.1088/1126-6708/2005/09/041
TUW-05-09, HIP-2005-25/TH, BI-TP 2005/17
hep-ph
null
Non-Abelian plasma instabilities have been proposed as a possible explanation for fast isotropization of the quark-gluon plasma produced in relativistic heavy-ion collisions. We study the real-time evolution of these instabilities in non-Abelian plasmas with a momentum-space anisotropy using a hard-loop effective theory that is discretized in the velocities of hard particles. We extend our previous results on the evolution of the most unstable modes, which are constant in directions transverse to the direction of anisotropy, from gauge group SU(2) to SU(3). We also present first full 3+1-dimensional simulation results based on velocity-discretized hard loops. In contrast to the effectively 1+1-dimensional transversely constant modes we find subexponential behaviour at late times.
[ { "created": "Tue, 31 May 2005 19:53:36 GMT", "version": "v1" }, { "created": "Wed, 31 Aug 2005 19:33:51 GMT", "version": "v2" }, { "created": "Sun, 25 Sep 2005 21:08:39 GMT", "version": "v3" } ]
2008-11-26
[ [ "Rebhan", "Anton", "" ], [ "Romatschke", "Paul", "" ], [ "Strickland", "Michael", "" ] ]
Non-Abelian plasma instabilities have been proposed as a possible explanation for fast isotropization of the quark-gluon plasma produced in relativistic heavy-ion collisions. We study the real-time evolution of these instabilities in non-Abelian plasmas with a momentum-space anisotropy using a hard-loop effective theory that is discretized in the velocities of hard particles. We extend our previous results on the evolution of the most unstable modes, which are constant in directions transverse to the direction of anisotropy, from gauge group SU(2) to SU(3). We also present first full 3+1-dimensional simulation results based on velocity-discretized hard loops. In contrast to the effectively 1+1-dimensional transversely constant modes we find subexponential behaviour at late times.
0904.4450
Ernest Ma
Ernest Ma (UC Riverside)
Radiative Inverse Seesaw: Verifiable New Mechanism of Neutrino Mass
11 pages, 3 figures
Phys.Rev.D80:013013,2009
10.1103/PhysRevD.80.013013
UCRHEP-T467 (April 2009)
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If the canonical seesaw mechanism alone is responsible for neutrino mass, i.e. m_nu = -m_D^2/m_N, it can neither be proved nor disproved at the TeV energy scale. A new verifiable mechanism of neutrino mass is proposed, using the "inverse" seesaw, with new physics at the TeV scale, such that m_nu = m_D^2 epsilon_L/m_N^2, where epsilon_L is a two-loop effect. Dark-matter candidates also appear naturally.
[ { "created": "Tue, 28 Apr 2009 17:31:50 GMT", "version": "v1" } ]
2009-09-02
[ [ "Ma", "Ernest", "", "UC Riverside" ] ]
If the canonical seesaw mechanism alone is responsible for neutrino mass, i.e. m_nu = -m_D^2/m_N, it can neither be proved nor disproved at the TeV energy scale. A new verifiable mechanism of neutrino mass is proposed, using the "inverse" seesaw, with new physics at the TeV scale, such that m_nu = m_D^2 epsilon_L/m_N^2, where epsilon_L is a two-loop effect. Dark-matter candidates also appear naturally.
1206.4024
Piotr Kotko
Piotr Kotko, Wojciech Slominski
General Mass Scheme for Jet Production in DIS
6 pages, 2 figures
null
10.1103/PhysRevD.86.094008
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a method for calculating DIS jet production cross sections in QCD at NLO accuracy with consistent treatment of heavy quarks. The scheme relies on the dipole subtraction method for jets, which we extend to all possible initial state splittings with heavy partons, so that the Aivazis-Collins-Olness-Tung massive collinear factorization scheme (ACOT) can be applied. As a first check of the formalism we recover the ACOT result for the heavy quark structure function using a dedicated Monte Carlo program.
[ { "created": "Mon, 18 Jun 2012 19:25:59 GMT", "version": "v1" } ]
2013-05-30
[ [ "Kotko", "Piotr", "" ], [ "Slominski", "Wojciech", "" ] ]
We propose a method for calculating DIS jet production cross sections in QCD at NLO accuracy with consistent treatment of heavy quarks. The scheme relies on the dipole subtraction method for jets, which we extend to all possible initial state splittings with heavy partons, so that the Aivazis-Collins-Olness-Tung massive collinear factorization scheme (ACOT) can be applied. As a first check of the formalism we recover the ACOT result for the heavy quark structure function using a dedicated Monte Carlo program.
1512.08172
Yachao Qian
Yachao Qian and Ismail Zahed
Spin Physics through QCD Instantons
19 pages, 14 figures
Annals Phys. 374, 314 (2016)
10.1016/j.aop.2016.09.002
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review some aspects of spin physics where QCD instantons play an important role. In particular, their large contributions in semi-inclusive deep-inelastic scattering and polarized proton on proton scattering. We also review their possible contribution in the $\mathcal{P}$-odd pion azimuthal charge correlations in peripheral $AA$ scattering at collider energies.
[ { "created": "Sun, 27 Dec 2015 05:34:17 GMT", "version": "v1" } ]
2021-02-10
[ [ "Qian", "Yachao", "" ], [ "Zahed", "Ismail", "" ] ]
We review some aspects of spin physics where QCD instantons play an important role. In particular, their large contributions in semi-inclusive deep-inelastic scattering and polarized proton on proton scattering. We also review their possible contribution in the $\mathcal{P}$-odd pion azimuthal charge correlations in peripheral $AA$ scattering at collider energies.
hep-ph/0609276
Rumin Wang
Ru-Min Wang, G. R. Lu, En-Ke Wang and Ya-Dong Yang
Probe the R-parity Violating Supersymmetry Effects in the $B^0_s-\bar{B}^0_s$ Mixing
11 pages, 4 figures, to appear in High Energy Physics And Nuclear Physcis
High Energy Phys.Nucl.Phys.31:332,2007
null
null
hep-ph
null
The recent measurements of the $B_s$ mass difference $\Delta M_s$ by the CDF and D{\O} collaborations are roughly consistent with the Standard Model predictions, therefore, these measurements will afford an opportunity to constrain new physics scenarios beyond the Standard Model. We consider the impact of the R-parity violating supersymmetry in the $B^0_s-\bar{B}^0_s$ mixing, and use the latest experimental results of $\Delta M_s$ to constrain the size of the R-parity violating tree level couplings in the $B^0_s-\bar{B}^0_s$ mixing. Then, using the constrained R-parity violating parameter space from $\Delta M_s$, we show the R-parity violating effects on the $B_s$ width difference $\Delta\Gamma_{s}$.
[ { "created": "Wed, 27 Sep 2006 07:34:05 GMT", "version": "v1" }, { "created": "Tue, 14 Nov 2006 12:15:46 GMT", "version": "v2" } ]
2011-03-23
[ [ "Wang", "Ru-Min", "" ], [ "Lu", "G. R.", "" ], [ "Wang", "En-Ke", "" ], [ "Yang", "Ya-Dong", "" ] ]
The recent measurements of the $B_s$ mass difference $\Delta M_s$ by the CDF and D{\O} collaborations are roughly consistent with the Standard Model predictions, therefore, these measurements will afford an opportunity to constrain new physics scenarios beyond the Standard Model. We consider the impact of the R-parity violating supersymmetry in the $B^0_s-\bar{B}^0_s$ mixing, and use the latest experimental results of $\Delta M_s$ to constrain the size of the R-parity violating tree level couplings in the $B^0_s-\bar{B}^0_s$ mixing. Then, using the constrained R-parity violating parameter space from $\Delta M_s$, we show the R-parity violating effects on the $B_s$ width difference $\Delta\Gamma_{s}$.
hep-ph/9506396
Fawzi Boudjema
M. Baillargeon, F.Boudjema, E. Chopin, V. Lafage
New Physics with three-photon events at LEP
No changes made from previous version, 34 pages, LateX, uses epsf, 11 .eps figs., full paper (including figs) is also available via WWW at http://lapphp0.in2p3.fr/preplapp/psth/lastee3g.ps.gz or via anonymous ftp at ftp:///lapphp0.in2p3.fr/pub/preprints-theorie/ftpee3g.uu
Z.Phys.C71:431-442,1996
10.1007/s002880050188
ENSLAPP-A-518/95 and FISIST/6-95/CFIF
hep-ph
null
The effect of the most general \z3gt vertex in the reaction $e^+e^- \ra 3\gamma$ is studied with a particular attention to LEP searches. We give exact analytical expressions including realistic cuts for the signal and present a detailed analysis based on a Monte Carlo that includes the effect of the irreducible $3\gamma$ QED cross section. As special applications we discuss the effect of heavy scalars, fermions and gauge bosons and comment on the ``monopole" connection.
[ { "created": "Thu, 22 Jun 1995 16:16:02 GMT", "version": "v1" }, { "created": "Fri, 8 Mar 1996 16:27:43 GMT", "version": "v2" } ]
2019-08-15
[ [ "Baillargeon", "M.", "" ], [ "Boudjema", "F.", "" ], [ "Chopin", "E.", "" ], [ "Lafage", "V.", "" ] ]
The effect of the most general \z3gt vertex in the reaction $e^+e^- \ra 3\gamma$ is studied with a particular attention to LEP searches. We give exact analytical expressions including realistic cuts for the signal and present a detailed analysis based on a Monte Carlo that includes the effect of the irreducible $3\gamma$ QED cross section. As special applications we discuss the effect of heavy scalars, fermions and gauge bosons and comment on the ``monopole" connection.
hep-ph/0411053
Dan Hooper
Edward A. Baltz and Dan Hooper
Kaluza-Klein Dark Matter, Electrons and Gamma Ray Telescopes
10 pages, 2 figures
JCAP 0507:001,2005
10.1088/1475-7516/2005/07/001
null
hep-ph astro-ph
null
Kaluza-Klein dark matter particles can annihilate efficiently into electron-positron pairs, providing a discrete feature (a sharp edge) in the cosmic $e^+ e^-$ spectrum at an energy equal to the particle's mass (typically several hundred GeV to one TeV). Although this feature is probably beyond the reach of satellite or balloon-based cosmic ray experiments (those that distinguish the charge and mass of the primary particle), gamma ray telescopes may provide an alternative detection method. Designed to observe very high-energy gamma-rays, ACTs also observe the diffuse flux of electron-induced electromagnetic showers. The GLAST satellite, designed for gamma ray astronomy, will also observe any high energy showers (several hundred GeV and above) in its calorimeter. We show that high-significance detections of an electron-positron feature from Kaluza-Klein dark matter annihilations are possible with GLAST, and also with ACTs such as HESS, VERITAS or MAGIC.
[ { "created": "Wed, 3 Nov 2004 17:53:00 GMT", "version": "v1" } ]
2011-03-23
[ [ "Baltz", "Edward A.", "" ], [ "Hooper", "Dan", "" ] ]
Kaluza-Klein dark matter particles can annihilate efficiently into electron-positron pairs, providing a discrete feature (a sharp edge) in the cosmic $e^+ e^-$ spectrum at an energy equal to the particle's mass (typically several hundred GeV to one TeV). Although this feature is probably beyond the reach of satellite or balloon-based cosmic ray experiments (those that distinguish the charge and mass of the primary particle), gamma ray telescopes may provide an alternative detection method. Designed to observe very high-energy gamma-rays, ACTs also observe the diffuse flux of electron-induced electromagnetic showers. The GLAST satellite, designed for gamma ray astronomy, will also observe any high energy showers (several hundred GeV and above) in its calorimeter. We show that high-significance detections of an electron-positron feature from Kaluza-Klein dark matter annihilations are possible with GLAST, and also with ACTs such as HESS, VERITAS or MAGIC.
0805.4267
Jan Nemchik
J. Nemchik (IEP SAS, Kosice & CTU, FNSPE, Prague), V. Petracek (CTU, FNSPE, Prague), I.K. Potashnikova (Santa Maria U., Valparaiso & Dubna, JINR), M. Sumbera (NPI, Rez)
Study of Nuclear Suppression at Large Forward Rapidities in d-Au Collisions at Relativistic and Ultrarelativistic Energies
Revised version (6 pages, 4 figures) to appear in Physical Review C
Phys.Rev.C78:025213,2008
10.1103/PhysRevC.78.025213
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study a strong suppression of the relative production rate (d-Au)/(p-p) for inclusive high-pT hadrons of different species at large forward rapidities (large Feynman xF). The model predictions calculated in the light-cone dipole approach are in a good agreement with the recent measurements by the BRAHMS and STAR Collaborations at the BNL Relativistic Heavy Ion Collider. We predict a similar suppression at large pT and large xF also at lower energies, where no effect of coherence is possible. It allows to exclude the saturation models or the models based on Color Glass Condensate from interpretation of nuclear effects.
[ { "created": "Wed, 28 May 2008 06:47:15 GMT", "version": "v1" }, { "created": "Tue, 15 Jul 2008 06:43:39 GMT", "version": "v2" }, { "created": "Wed, 6 Aug 2008 06:42:56 GMT", "version": "v3" } ]
2008-11-26
[ [ "Nemchik", "J.", "", "IEP SAS, Kosice & CTU, FNSPE, Prague" ], [ "Petracek", "V.", "", "CTU,\n FNSPE, Prague" ], [ "Potashnikova", "I. K.", "", "Santa Maria U., Valparaiso & Dubna, JINR" ], [ "Sumbera", "M.", "", "NPI, Rez" ] ]
We study a strong suppression of the relative production rate (d-Au)/(p-p) for inclusive high-pT hadrons of different species at large forward rapidities (large Feynman xF). The model predictions calculated in the light-cone dipole approach are in a good agreement with the recent measurements by the BRAHMS and STAR Collaborations at the BNL Relativistic Heavy Ion Collider. We predict a similar suppression at large pT and large xF also at lower energies, where no effect of coherence is possible. It allows to exclude the saturation models or the models based on Color Glass Condensate from interpretation of nuclear effects.
hep-ph/9909406
Alaa Abd El-Hady
A. Abd El-Hady, J. H. Mu\~noz, J.P. Vary
Semileptonic and non-leptonic B_c decays
11 Pages, 1 Postscript figure
Phys.Rev.D62:014019,2000
10.1103/PhysRevD.62.014019
ISU-NP-99-08, IITAP-99-010
hep-ph
null
We make predictions for the exclusive semileptonic and the non-leptonic decay widths of the B_c meson. We evaluate the B_c semileptonic form factors for different decay channels in a relativistic model, and use factorization to obtain the non-leptonic decay widths.
[ { "created": "Thu, 16 Sep 1999 19:50:04 GMT", "version": "v1" } ]
2011-07-18
[ [ "El-Hady", "A. Abd", "" ], [ "Muñoz", "J. H.", "" ], [ "Vary", "J. P.", "" ] ]
We make predictions for the exclusive semileptonic and the non-leptonic decay widths of the B_c meson. We evaluate the B_c semileptonic form factors for different decay channels in a relativistic model, and use factorization to obtain the non-leptonic decay widths.
1007.4328
German Rodrigo
German Rodrigo and Paola Ferrario
Charge asymmetry: a theory appraisal
Presented at 3rd International Workshop on Top Quark Physics (TOP 2010), Bruges, Belgium, 31 May - 4 Jun 2010. 8 pages
Nuovo Cim.C33:04,2010
10.1393/ncc/i2010-10646-5
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The most recent measurements at Tevatron of the charge asymmetry in top-antitop quark pair production reduce the discrepancy with the Standard Model from 2sigma to 1.7sigma, and open a little window, at 95% C.L., for negative contributions to the charge asymmetry beyond the SM. We update our analysis for colour octet gauge bosons or axigluons in flavour universal and flavour non universal scenarios. We review other possible models and make an educated guess on their parameter space allowed by the new measurements. Finally, we comment on the prospects to measure the charge asymmetry at the LHC.
[ { "created": "Sun, 25 Jul 2010 16:02:29 GMT", "version": "v1" } ]
2022-03-02
[ [ "Rodrigo", "German", "" ], [ "Ferrario", "Paola", "" ] ]
The most recent measurements at Tevatron of the charge asymmetry in top-antitop quark pair production reduce the discrepancy with the Standard Model from 2sigma to 1.7sigma, and open a little window, at 95% C.L., for negative contributions to the charge asymmetry beyond the SM. We update our analysis for colour octet gauge bosons or axigluons in flavour universal and flavour non universal scenarios. We review other possible models and make an educated guess on their parameter space allowed by the new measurements. Finally, we comment on the prospects to measure the charge asymmetry at the LHC.
2012.09813
Lu Meng
Lu Meng, Bo Wang and Shi-Lin Zhu
Predicting the $\bar{D}_s^{(*)} D_s^{(*)}$ bound states as the partners of $X(3872)$
9 pages, 5 figures; add the coupled-channel discussions in EFT; to be published in Science Bulletin
Sci.Bull. 66 (2021) 1288-1295
10.1016/j.scib.2021.03.016
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we investigate the SU(3) flavor symmetry, heavy quark spin symmetry and their breaking effects in the di-meson systems. We prove the existence of the $[\bar{D}_{s}^{*}D_{s}^{*}]^{0^{++}}$, $[\bar{D}_{s}^{*}D_{s}/\bar{D}_{s}^{}D_{s}^*]^{1^{+-}}$, and $[\bar{D}_{s}^{*}D_{s}^{*}]^{1^{+-}}$ bound states as the consequence of two prerequisites in the SU(3) flavor symmetry and heavy quark spin symmetry. The first prerequisite, the $X(3872)$ as the weakly $\bar{D}^{*}D/\bar{D} D^{*}$ bound state is supported by its mass and decay branching ratios. The second prerequisite, the existence of the $[\bar{D}_{s}D_{s}]^{0^{++}}$ bound state is supported by the lattice QCD calculation [arXiv:2011.02542(hep-lat)] and the observation of $\chi_{c0}(3930)$ by the LHCb Collaboration[Phys.Rev.Lett.125,242001, Phys.Rev.D102,112003]. We hope the future experimental analyses can search for these bound states in the $B\to D_{(s)}^{(*)}\bar{D}^{(*)}_{(s)}h$ processes ($h$ denotes the light hadrons). The $[\bar{D}_{s}^{*}D_{s}^{*}]^{0^{++}}$ bound state is also expected to be reconstructed in the $J/\psi \phi$ final state in the $B\to J/\psi \phi K$ decay.
[ { "created": "Thu, 17 Dec 2020 18:29:08 GMT", "version": "v1" }, { "created": "Mon, 21 Dec 2020 10:25:53 GMT", "version": "v2" }, { "created": "Tue, 9 Mar 2021 19:29:46 GMT", "version": "v3" } ]
2021-07-02
[ [ "Meng", "Lu", "" ], [ "Wang", "Bo", "" ], [ "Zhu", "Shi-Lin", "" ] ]
In this work, we investigate the SU(3) flavor symmetry, heavy quark spin symmetry and their breaking effects in the di-meson systems. We prove the existence of the $[\bar{D}_{s}^{*}D_{s}^{*}]^{0^{++}}$, $[\bar{D}_{s}^{*}D_{s}/\bar{D}_{s}^{}D_{s}^*]^{1^{+-}}$, and $[\bar{D}_{s}^{*}D_{s}^{*}]^{1^{+-}}$ bound states as the consequence of two prerequisites in the SU(3) flavor symmetry and heavy quark spin symmetry. The first prerequisite, the $X(3872)$ as the weakly $\bar{D}^{*}D/\bar{D} D^{*}$ bound state is supported by its mass and decay branching ratios. The second prerequisite, the existence of the $[\bar{D}_{s}D_{s}]^{0^{++}}$ bound state is supported by the lattice QCD calculation [arXiv:2011.02542(hep-lat)] and the observation of $\chi_{c0}(3930)$ by the LHCb Collaboration[Phys.Rev.Lett.125,242001, Phys.Rev.D102,112003]. We hope the future experimental analyses can search for these bound states in the $B\to D_{(s)}^{(*)}\bar{D}^{(*)}_{(s)}h$ processes ($h$ denotes the light hadrons). The $[\bar{D}_{s}^{*}D_{s}^{*}]^{0^{++}}$ bound state is also expected to be reconstructed in the $J/\psi \phi$ final state in the $B\to J/\psi \phi K$ decay.
1403.7415
Gustavo A. Contrera
Gustavo A. Contrera, William Spinella, Milva Orsaria and Fridolin Weber
Hadron-Quark Phase Transition in Quark-Hybrid Stars
7 pages, 2 figures. Contribution to VI International Workshop on Astronomy and Relativistic Astrophysics (IWARA 2013)
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The recent discovery of the two-solar mass neutron stars $J1614-2230~(1.97 \pm 0.04 M_{\odot})$ and $J0348+0432~(2.01 \pm 0.04 M_{\odot})$ allows to consider the possible existence of deconfined quarks in the cores of neutron stars. Based on a non-local extension of the $SU(3)$ Nambu Jona-Lasinio model with vector interactions to describe the quark matter phase, and a non-linear Walecka model to represent the hadronic phase, a phase transition between these two phases can be constructed via the Gibbs conditions and imposing global electric charge neutrality condition. Depending on the strength of quark vector repulsion, we find that an extended region made of a mixed phase of quarks and hadrons may exist in high-mass neutron stars with masses up to $2.0-2.4 M_{\odot}$. The radii of these objects are between $12$ and $13$ km, as expected for neutron stars.
[ { "created": "Fri, 28 Mar 2014 15:17:51 GMT", "version": "v1" } ]
2014-03-31
[ [ "Contrera", "Gustavo A.", "" ], [ "Spinella", "William", "" ], [ "Orsaria", "Milva", "" ], [ "Weber", "Fridolin", "" ] ]
The recent discovery of the two-solar mass neutron stars $J1614-2230~(1.97 \pm 0.04 M_{\odot})$ and $J0348+0432~(2.01 \pm 0.04 M_{\odot})$ allows to consider the possible existence of deconfined quarks in the cores of neutron stars. Based on a non-local extension of the $SU(3)$ Nambu Jona-Lasinio model with vector interactions to describe the quark matter phase, and a non-linear Walecka model to represent the hadronic phase, a phase transition between these two phases can be constructed via the Gibbs conditions and imposing global electric charge neutrality condition. Depending on the strength of quark vector repulsion, we find that an extended region made of a mixed phase of quarks and hadrons may exist in high-mass neutron stars with masses up to $2.0-2.4 M_{\odot}$. The radii of these objects are between $12$ and $13$ km, as expected for neutron stars.
2006.09443
Artem Lipatov
S.J. Brodsky, G.I. Lykasov, A.V. Lipatov, J. Smiesko
Novel Heavy-Quark Physics Phenomena
80 pages, 32 figures. review article
null
null
SLAC-PUB-17538
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review the current understanding of heavy quark parton distributions in nucleons and their impact on deep inelastic scattering, collider physics, and other processes at high energies. The determination of the heavy-quark parton distribution functions is particularly significant for the analysis of hard processes at LHC energies, including the forward rapidity high $x_\mathrm{F}$ domain. The contribution of "intrinsic" heavy quarks, which are multiply connected to the valence quarks of nucleons, is reviewed within non-perturbative physics which provides new information on the fundamental structure of hadrons in QCD. A new prediction for the non-perturbative intrinsic charm-anticharm asymmetry of the proton eigenstate has recently been obtained from a QCD lattice gauge theory calculation of the proton's $G_\mathrm{E}^p(Q^2)$ form factor. This form factor only arises from non-valence quarks and anti-quarks if they have different contributions in the proton's eigenstate. This result, together with the exclusive and inclusive connection and analytic constraints on the form of hadronic structure functions from Light-Front Holographic QCD (LFHQCD) predicts a significant non-perturbative $c(x,Q) - \bar{c}(x,Q)$ asymmetry in the proton structure function at high $x$, consistent with the dynamics predicted by intrinsic charm models. Recent ATLAS data on the associated production of prompt photons and charm-quark jets in $pp$ collisions at $\sqrt{s} = 8$ TeV has provided new constraints on non-perturbative intrinsic charm and tests of the LGTH predictions. We also focus on other experimental observables which have high sensitivity to the intrinsic heavy contributions to PDFs.
[ { "created": "Tue, 16 Jun 2020 18:39:48 GMT", "version": "v1" }, { "created": "Mon, 29 Jun 2020 08:45:55 GMT", "version": "v2" } ]
2020-06-30
[ [ "Brodsky", "S. J.", "" ], [ "Lykasov", "G. I.", "" ], [ "Lipatov", "A. V.", "" ], [ "Smiesko", "J.", "" ] ]
We review the current understanding of heavy quark parton distributions in nucleons and their impact on deep inelastic scattering, collider physics, and other processes at high energies. The determination of the heavy-quark parton distribution functions is particularly significant for the analysis of hard processes at LHC energies, including the forward rapidity high $x_\mathrm{F}$ domain. The contribution of "intrinsic" heavy quarks, which are multiply connected to the valence quarks of nucleons, is reviewed within non-perturbative physics which provides new information on the fundamental structure of hadrons in QCD. A new prediction for the non-perturbative intrinsic charm-anticharm asymmetry of the proton eigenstate has recently been obtained from a QCD lattice gauge theory calculation of the proton's $G_\mathrm{E}^p(Q^2)$ form factor. This form factor only arises from non-valence quarks and anti-quarks if they have different contributions in the proton's eigenstate. This result, together with the exclusive and inclusive connection and analytic constraints on the form of hadronic structure functions from Light-Front Holographic QCD (LFHQCD) predicts a significant non-perturbative $c(x,Q) - \bar{c}(x,Q)$ asymmetry in the proton structure function at high $x$, consistent with the dynamics predicted by intrinsic charm models. Recent ATLAS data on the associated production of prompt photons and charm-quark jets in $pp$ collisions at $\sqrt{s} = 8$ TeV has provided new constraints on non-perturbative intrinsic charm and tests of the LGTH predictions. We also focus on other experimental observables which have high sensitivity to the intrinsic heavy contributions to PDFs.
2306.04002
Ahmad Moursy ElSayed
Anish Ghoshal, Ahmad Moursy and Qaisar Shafi
Cosmological probes of Grand Unification: Primordial Blackholes & scalar-induced Gravitational Waves
In the revised version any inadvertent text overlap with other papers has been removed, the appendix is removed, and previous sections 5 and 6 have been merged. All results including figures and conclusions remain intact
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the inflationary cosmology involving an SU(5) GUT (grand unified theory) singlet scalar with non-minimal coupling to the Ricci scalar. In this scenario the scale of grand unification is set by the inflaton vev when the inflaton rolls down its potential towards its minimum $v$, thereby relating inflationary dynamics to GUT symmetry breaking with a prediction $r \simeq 0.025$ for the tensor-to-scalar ratio to be tested by the next generation CMB experiments. We show in this inflationary framework involving inflection-point how a suitable choice of parameters in $SU(5)$ leads to a bump in the scalar power spectrum with production of Primordial Blackholes (PBH) of masses $10^{17}-10^{18}$g ($ 10 - 100 M_\odot$). We derive the constraints on the self quartic and mixed quartic couplings of the inflaton in SU(5) that are consistent with the inflationary analysis. Moreover, we also show that this scenario leads to large amplitude induced second-order tensor perturbations propagating as Gravitational Waves (GW) with amplitude $\Omega_{\rm GW}h^2 \sim 10^{-17}$ and peak frequency $f_{\rm peak} \sim$ (0.1 - 1) Hz, which can be detected in the next generation GW observatories like LISA, BBO, ET, etc. Thus, we unify the $SU(5)$ framework with PBH via inflection-point inflation showing how the upcoming measurements of PBH and GW will enable us to probe the scale of $SU(5)$ symmetry breaking, and thereby complementing the laboratory based experiments. We also discuss scenarios involving the Pati-Salam and Trinification gauge groups and its impact on quartic and mixed-quartic couplings that may lead to PBH and detectable GW signals.
[ { "created": "Tue, 6 Jun 2023 20:29:19 GMT", "version": "v1" }, { "created": "Mon, 12 Jun 2023 15:33:15 GMT", "version": "v2" } ]
2023-06-13
[ [ "Ghoshal", "Anish", "" ], [ "Moursy", "Ahmad", "" ], [ "Shafi", "Qaisar", "" ] ]
We investigate the inflationary cosmology involving an SU(5) GUT (grand unified theory) singlet scalar with non-minimal coupling to the Ricci scalar. In this scenario the scale of grand unification is set by the inflaton vev when the inflaton rolls down its potential towards its minimum $v$, thereby relating inflationary dynamics to GUT symmetry breaking with a prediction $r \simeq 0.025$ for the tensor-to-scalar ratio to be tested by the next generation CMB experiments. We show in this inflationary framework involving inflection-point how a suitable choice of parameters in $SU(5)$ leads to a bump in the scalar power spectrum with production of Primordial Blackholes (PBH) of masses $10^{17}-10^{18}$g ($ 10 - 100 M_\odot$). We derive the constraints on the self quartic and mixed quartic couplings of the inflaton in SU(5) that are consistent with the inflationary analysis. Moreover, we also show that this scenario leads to large amplitude induced second-order tensor perturbations propagating as Gravitational Waves (GW) with amplitude $\Omega_{\rm GW}h^2 \sim 10^{-17}$ and peak frequency $f_{\rm peak} \sim$ (0.1 - 1) Hz, which can be detected in the next generation GW observatories like LISA, BBO, ET, etc. Thus, we unify the $SU(5)$ framework with PBH via inflection-point inflation showing how the upcoming measurements of PBH and GW will enable us to probe the scale of $SU(5)$ symmetry breaking, and thereby complementing the laboratory based experiments. We also discuss scenarios involving the Pati-Salam and Trinification gauge groups and its impact on quartic and mixed-quartic couplings that may lead to PBH and detectable GW signals.
0710.3346
Stefan Hesselbach
David Eriksson, Stefan Hesselbach, Johan Rathsman
Associated charged Higgs and W boson production in the MSSM at the LHC
Submitted for the SUSY07 proceedings, 4 pages, LaTeX, 7 eps figures
null
null
SHEP-07-42
hep-ph
null
We investigate the associated production of charged Higgs bosons (H^\pm) and W bosons at the CERN Large Hadron Collider, using the leptonic decay H^+ -> tau^+ nu_tau and hadronic W decay, within different scenarios of the Minimal Supersymmetric Standard Model (MSSM) with both real and complex parameters. Performing a parton level study we show how the irreducible Standard Model background from W + 2 jets can be controlled by applying appropriate cuts. In the standard m_h^max scenario we find a viable signal for large tan beta and intermediate H^\pm masses (~ m_t). In MSSM scenarios with large mass-splittings among the heavy Higgs bosons the cross-section can be resonantly enhanced by factors up to one hundred, with a strong dependence on the CP-violating phases.
[ { "created": "Wed, 17 Oct 2007 16:29:11 GMT", "version": "v1" } ]
2007-10-18
[ [ "Eriksson", "David", "" ], [ "Hesselbach", "Stefan", "" ], [ "Rathsman", "Johan", "" ] ]
We investigate the associated production of charged Higgs bosons (H^\pm) and W bosons at the CERN Large Hadron Collider, using the leptonic decay H^+ -> tau^+ nu_tau and hadronic W decay, within different scenarios of the Minimal Supersymmetric Standard Model (MSSM) with both real and complex parameters. Performing a parton level study we show how the irreducible Standard Model background from W + 2 jets can be controlled by applying appropriate cuts. In the standard m_h^max scenario we find a viable signal for large tan beta and intermediate H^\pm masses (~ m_t). In MSSM scenarios with large mass-splittings among the heavy Higgs bosons the cross-section can be resonantly enhanced by factors up to one hundred, with a strong dependence on the CP-violating phases.
1011.5342
Guido Altarelli
Guido Altarelli
Status of Neutrino Masses and Mixing in 2010
15 pages, 2 figures. Talk given at the Quarks, Strings and the Cosmos - Hector Rubinstein Memorial Symposium, August 09-11, 2010, AlbaNova, Stockholm, Sweden
null
null
RM3-TH/10-12, CERN-PH-TH/2010-280
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a short summary of our present knowledge and understanding of neutrino masses and mixing.
[ { "created": "Wed, 24 Nov 2010 11:31:34 GMT", "version": "v1" } ]
2010-11-25
[ [ "Altarelli", "Guido", "" ] ]
We present a short summary of our present knowledge and understanding of neutrino masses and mixing.
hep-ph/0104208
Massimo Di Pierro
Massimo Di Pierro and Estia Eichten
Excited Heavy-Light Systems and Hadronic Transitions
41 pages (figures included)
Phys.Rev. D64 (2001) 114004
10.1103/PhysRevD.64.114004
Fermilab Pub-01/033-T
hep-ph hep-ex hep-lat
null
A detailed study of orbital and radial excited states in D, Ds, B and B_s systems is performed. The chiral quark model provides the framework for the calculation of pseudoscalar meson (pi, K, ...) hadronic transitions among heavy-light excited and ground states. To calculate the excited states masses and wavefunctions, we must resort to a relativistic quark model. Our model includes the leading order corrections in 1/m_(c,b) (e.g. mixing). Numerical results for masses and light hadronic transition rates are compared to existing experimental data. The effective coupling of the chiral quark model can be determined by comparing with independent results from lattice simulations (g^8_A = 0.53 +-/- 0.11) or fitting to known widths (g^8_A = 0.82 +-/- 0.09).
[ { "created": "Fri, 20 Apr 2001 19:20:28 GMT", "version": "v1" }, { "created": "Mon, 23 Apr 2001 15:28:41 GMT", "version": "v2" }, { "created": "Tue, 14 Aug 2001 21:21:20 GMT", "version": "v3" } ]
2009-11-07
[ [ "Di Pierro", "Massimo", "" ], [ "Eichten", "Estia", "" ] ]
A detailed study of orbital and radial excited states in D, Ds, B and B_s systems is performed. The chiral quark model provides the framework for the calculation of pseudoscalar meson (pi, K, ...) hadronic transitions among heavy-light excited and ground states. To calculate the excited states masses and wavefunctions, we must resort to a relativistic quark model. Our model includes the leading order corrections in 1/m_(c,b) (e.g. mixing). Numerical results for masses and light hadronic transition rates are compared to existing experimental data. The effective coupling of the chiral quark model can be determined by comparing with independent results from lattice simulations (g^8_A = 0.53 +-/- 0.11) or fitting to known widths (g^8_A = 0.82 +-/- 0.09).
hep-ph/0106219
Scott Thomas
Steven B. Giddings and Scott Thomas
High Energy Colliders as Black Hole Factories: The End of Short Distance Physics
Latex, 28 pages. v4: minor changes, largely to agree with published version; appendix added comparing conventions
Phys.Rev. D65 (2002) 056010
10.1103/PhysRevD.65.056010
null
hep-ph gr-qc hep-ex hep-th
null
If the fundamental Planck scale is of order a TeV, as the case in some extra-dimensions scenarios, future hadron colliders such as the Large Hadron Collider will be black hole factories. The non-perturbative process of black hole formation and decay by Hawking evaporation gives rise to spectacular events with up to many dozens of relatively hard jets and leptons, with a characteristic ratio of hadronic to leptonic activity of roughly 5:1. The total transverse energy of such events is typically a sizeable fraction of the beam energy. Perturbative hard scattering processes at energies well above the Planck scale are cloaked behind a horizon, thus limiting the ability to probe short distances. The high energy black hole cross section grows with energy at a rate determined by the dimensionality and geometry of the extra dimensions. This dependence therefore probes the extra dimensions at distances larger than the Planck scale.
[ { "created": "Tue, 19 Jun 2001 22:58:46 GMT", "version": "v1" }, { "created": "Wed, 20 Jun 2001 22:53:17 GMT", "version": "v2" }, { "created": "Thu, 28 Jun 2001 22:58:26 GMT", "version": "v3" }, { "created": "Wed, 26 Jun 2002 02:27:54 GMT", "version": "v4" } ]
2009-11-07
[ [ "Giddings", "Steven B.", "" ], [ "Thomas", "Scott", "" ] ]
If the fundamental Planck scale is of order a TeV, as the case in some extra-dimensions scenarios, future hadron colliders such as the Large Hadron Collider will be black hole factories. The non-perturbative process of black hole formation and decay by Hawking evaporation gives rise to spectacular events with up to many dozens of relatively hard jets and leptons, with a characteristic ratio of hadronic to leptonic activity of roughly 5:1. The total transverse energy of such events is typically a sizeable fraction of the beam energy. Perturbative hard scattering processes at energies well above the Planck scale are cloaked behind a horizon, thus limiting the ability to probe short distances. The high energy black hole cross section grows with energy at a rate determined by the dimensionality and geometry of the extra dimensions. This dependence therefore probes the extra dimensions at distances larger than the Planck scale.
hep-ph/9808230
Gaston Krein
D. Drechsel and G. Krein
The Gerasimov-Drell-Hearn sum rule and the single-pion photoproduction multipole E0+ close to threshold
9 pages, latex, 1 figure, to appear in Phys. Rev. D
Phys.Rev. D58 (1998) 116009
10.1103/PhysRevD.58.116009
null
hep-ph nucl-ex nucl-th
null
The long-standing discrepancy between the Gerasimov-Drell-Hearn sum rule and the analysis of pion photoproduction multipoles is greatly diminished by use of s-wave multipoles that are in accord with the predictions of chiral perturbation theory and describe the experimental data in the threshold region. The remaining difference may be due to contributions of channels with more pions and/or heavier mesons whose contributions to the sum rule remain to be investigated by a direct measurement of the photoabsorption cross sections.
[ { "created": "Wed, 5 Aug 1998 09:28:31 GMT", "version": "v1" } ]
2009-10-31
[ [ "Drechsel", "D.", "" ], [ "Krein", "G.", "" ] ]
The long-standing discrepancy between the Gerasimov-Drell-Hearn sum rule and the analysis of pion photoproduction multipoles is greatly diminished by use of s-wave multipoles that are in accord with the predictions of chiral perturbation theory and describe the experimental data in the threshold region. The remaining difference may be due to contributions of channels with more pions and/or heavier mesons whose contributions to the sum rule remain to be investigated by a direct measurement of the photoabsorption cross sections.
2109.03248
Taewook Youn
Can Kilic, Christopher B. Verhaaren and Taewook Youn
Twin Quark Dark Matter From Cogenesis
32 pages, 11 figures; v3: Minor changes. Matches published version
null
10.1103/PhysRevD.104.116018
UTTG 16-2021
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend the fraternal twin Higgs scenario to include a novel dark matter candidate as well as a mechanism for generating a matter/antimatter asymmetry in both sectors. A spontaneous breaking of twin color results in quark degrees of freedom that are singlets under the residual twin color group. These twin-color-singlet quarks, along with a subdominant component of twin leptons, constitute the asymmetric dark matter. The asymmetry between matter in antimatter in both sectors is co-generated from the decay of singlet fermions that provide an additional portal between the visible and twin sectors. We discuss the phenomenological aspects of this model, evaluating constraints on the parameter space and highlighting promising discovery channels in future experiments. We briefly discuss how the discovery of signals in multiple experiments may help establish the connection between the mechanisms that address the naturalness, dark matter and matter/antimatter asymmetry puzzles.
[ { "created": "Tue, 7 Sep 2021 18:00:02 GMT", "version": "v1" }, { "created": "Wed, 15 Sep 2021 04:22:00 GMT", "version": "v2" }, { "created": "Thu, 6 Jan 2022 09:45:38 GMT", "version": "v3" } ]
2022-01-07
[ [ "Kilic", "Can", "" ], [ "Verhaaren", "Christopher B.", "" ], [ "Youn", "Taewook", "" ] ]
We extend the fraternal twin Higgs scenario to include a novel dark matter candidate as well as a mechanism for generating a matter/antimatter asymmetry in both sectors. A spontaneous breaking of twin color results in quark degrees of freedom that are singlets under the residual twin color group. These twin-color-singlet quarks, along with a subdominant component of twin leptons, constitute the asymmetric dark matter. The asymmetry between matter in antimatter in both sectors is co-generated from the decay of singlet fermions that provide an additional portal between the visible and twin sectors. We discuss the phenomenological aspects of this model, evaluating constraints on the parameter space and highlighting promising discovery channels in future experiments. We briefly discuss how the discovery of signals in multiple experiments may help establish the connection between the mechanisms that address the naturalness, dark matter and matter/antimatter asymmetry puzzles.
hep-ph/0401048
Schweizer Julia
J. Schweizer (Bern University)
Decay widths and energy shifts of pi pi and pi K atoms
Version to be published in Phys. Lett. B. Four references added, correlation matrix for pi K scattering lengths updated, uncertainty of Delta E^h_1 in table 2 adapted. 14 pages, 1 figure
Phys.Lett. B587 (2004) 33-40
10.1016/j.physletb.2004.03.007
null
hep-ph
null
We calculate the S-wave decay widths and energy shifts for pi pi and pi K atoms in the framework of QCD+QED. The evaluation - valid at next-to-leading order in isospin symmetry breaking - is performed within a non-relativistic effective field theory. The results are of interest for future hadronic atom experiments.
[ { "created": "Fri, 9 Jan 2004 13:02:28 GMT", "version": "v1" }, { "created": "Wed, 31 Mar 2004 09:20:19 GMT", "version": "v2" } ]
2009-11-10
[ [ "Schweizer", "J.", "", "Bern University" ] ]
We calculate the S-wave decay widths and energy shifts for pi pi and pi K atoms in the framework of QCD+QED. The evaluation - valid at next-to-leading order in isospin symmetry breaking - is performed within a non-relativistic effective field theory. The results are of interest for future hadronic atom experiments.
hep-ph/0203037
Shoichi Ichinose
Shoichi Ichinose
CP-Violation in Kaluza-Klein and Randall-Sundrum Theories
3 pages, 2 figures, Proceedings of the Fifth KEK Topical Conference -Frontiers in Flavor Physics-
Nucl.Phys.Proc.Suppl. 111 (2002) 297-299
10.1016/S0920-5632(02)01727-9
US-02-03
hep-ph hep-th
null
The Kaluza-Klein theory and Randall-Sundrum theory are examined comparatively, with focus on the five dimensional (Dirac) fermion and the dimensional reduction to four dimensions. They are treated in the Cartan formalism. The chiral property, localization, anomaly phenomena are examined. The electric and magnetic dipole moment terms naturally appear. The order estimation of the couplings is done. This is a possible origin of the CP-violation.
[ { "created": "Tue, 5 Mar 2002 08:32:47 GMT", "version": "v1" } ]
2009-11-07
[ [ "Ichinose", "Shoichi", "" ] ]
The Kaluza-Klein theory and Randall-Sundrum theory are examined comparatively, with focus on the five dimensional (Dirac) fermion and the dimensional reduction to four dimensions. They are treated in the Cartan formalism. The chiral property, localization, anomaly phenomena are examined. The electric and magnetic dipole moment terms naturally appear. The order estimation of the couplings is done. This is a possible origin of the CP-violation.