Wed·Sep 30, 2015Wednesday·September 30, 2015

1. 01*

   Self-similarity of strangeness production in pp collisions at RHIC

   M. Tokarev (1) · I. Zborovsky (2) ((1) Veksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia (2) Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Rez, Czech Republic)

   New experimental data on transverse momentum spectra of strange particles (KS0, K-, K*, phi,...) produced in pp collisions at sqrt s = 200 GeV obtained by the STAR and PHENIX collaborations at RHIC are analysed in the framework of z-scaling approach. Scaling properties of the data z-presentation are illustrated. Self-similarity of strange particle production is discussed. A microscopic scenario of constituent interactions developed within the z-scaling approach is used to study constituent energy loss, proton momentum fraction and recoil mass in dependence on the transverse momentum, strangeness, and mass of the inclusive particle. The obtained results can be useful for understanding strangeness origin, for searching for new physics with strange probes and can serve as a benchmark for complex analyses of self-similar features of strange production in heavy ion collisions.

   hep-phnucl-exnucl-thJ.Phys.Conf.Ser.(2016)·4 citations
2. 02*

   Theoretical Aspects of Flavour and CP Violation in the Lepton Sector

   Ferruccio Feruglio🇮🇹

   We review flavour and CP violations in the lepton sector as probes of new physics beyond the standard model and its minimal extensions accommodating massive neutrinos. After recalling the main experimental bounds and the future perspectives, we summarize the limits on a set of dimension-six gauge-invariant operators, pointing to a scale of new physics much larger than the electroweak scale. If we insist on having new physics at the TeV scale, as demanded by most of the standard model extensions addressing the gauge hierarchy problem, we should rely on special mechanisms to deplete flavour and CP violations in the charged lepton sector. We comment on the capability of partial compositeness in reconciling the absence of signals with a scale of new physics accessible to the LHC.

   hep-ph11 citations
3. 03*

   A covariant model for the negative parity resonances of the nucleon

   G. Ramalho🇧🇷

   We present a model for the ${\gamma }^{\ast }N\to N^{\ast }$ helicity amplitudes, where $N$ is the nucleon and $N^{\ast }$ is a negative parity nucleon excitation, member of the $SU(6)$-multiplet $[70,1^{-}]$. The model combines the results from the single quark transition model for the helicity amplitudes with the results of the covariant spectator quark model for the ${\gamma }^{\ast }N\to N^{\ast }(1535)$ and ${\gamma }^{\ast }N\to N^{\ast }(1520)$ transitions. With the knowledge of the amplitudes $A_{1/2}$ and $A_{3/2}$ for those transitions we calculate three independent coefficients defined by the single quark transition model and make predictions for the helicity amplitudes associated with the ${\gamma }^{\ast }N\to N^{\ast }(1650)$, ${\gamma }^{\ast }N\to N^{\ast }(1700)$, ${\gamma }^{\ast }N\to \Delta (1620)$, and ${\gamma }^{\ast }N\to \Delta (1700)$ transitions. In order to facilitate the comparison with future experimental data at high $Q^2$, we provide also simple parametrizations for the amplitudes, compatible with the expected falloff at high $Q^2$.

   hep-phhep-exhep-latnucl-ex+1J.Phys.Conf.Ser.(2016)·0 citations
4. 04*

   Flooded Dark Matter and S Level Rise

   Lisa Randall🇺🇸 · Jakub Scholtz🇺🇸 · James Unwin🇺🇸

   Most dark matter (DM) models set the DM relic density by some interaction with Standard Model particles. Such models generally assume the existence of Standard Model particles early on, with the DM relic density a later consequence of those interactions. Perhaps a more compelling assumption is that DM is not part of the Standard Model sector and a population of DM too is generated at the end of inflation. This democratic assumption does not necessarily provide a natural value for the DM relic density, and superficially leads to too much entropy in the dark sector. We address the latter issue by the late decay of heavy particles produced at early times, associating the DM relic density with the lifetime of a long-lived state. We ask what it would take for this scenario to be compatible with observations in what we call Flooded Dark Matter (FDM) and discuss several interesting consequences. One is that DM can be very light and furthermore, light DM is in some sense the most natural scenario in FDM as it is compatible with larger couplings of the decaying particle. Moreover, the decay of the field with the smallest coupling and hence the longest lifetime dominates the entropy and possibly the matter content of the Universe, a principle we refer to as 'Maximum Baroqueness'. We also show that the dark sector should be colder than the ordinary sector, relaxing the free-streaming constraints on light DM. We will discuss the implications for the core-cusp problem in a follow-up paper. FDM also has interesting baryogenesis implications. One possibility is that both DM and baryon asymmetries are simultaneously diluted by a late entropy dump. Alternatively, FDM is compatible with an elegant non-thermal leptogenesis implementation in which decays of a heavy RH neutrino lead to late time reheating of the Standard Model and provide suitable conditions for creation of a lepton asymmetry.

   hep-phastro-ph.COhep-thJHEP(2016)·55 citations
5. 05*

   Self-consistent solitons for vacuum decay in radiatively generated potentials

   Bjorn Garbrecht🇩🇪 · Peter Millington🇩🇪

   We use a Green's function approach in order to develop a method for calculating the tunneling rate between radiatively-generated non-degenerate vacua. We apply this to a model that exhibits spontaneous symmetry breaking via the Coleman-Weinberg mechanism, where we determine the self-consistent tunneling configuration and illustrate the impact of gradient effects that arise from accounting for the underlying space-time inhomogeneity.

   hep-phhep-thPRD(2015)·56 citations
6. 06*

   Fermionic Semi-Annihilating Dark Matter

   Yi Cai🇦🇺 · Andrew Paul Spray🇦🇺

   Semi-annihilation is a generic feature of dark matter theories with symmetries larger than Z2. We investigate two examples with multi-component dark sectors comprised of an SU(2)L singlet or triplet fermion besides a scalar singlet. These are respectively the minimal fermionic semi-annihilating model, and the minimal case for a gauge-charged fermion. We study the relevant dark matter phenomenology, including the interplay of semi-annihilation and the Sommerfeld effect. We demonstrate that semi-annihilation in the singlet model can explain the gamma ray excess from the galactic center. For the triplet model we scan the parameter space, and explore how signals and constraints are modified by semi-annihilation. We find that the entire region where the model comprises all the observed dark matter is accessible to current and planned direct and indirect searches.

   hep-phJHEP(2016)·35 citations
7. 07*

   ChPT parameters from tau-decay data

   A. Rodríguez-Sánchez🇪🇸 · M. González-Alonso🇫🇷 · A. Pich🇪🇸

   Using the updated ALEPH V-A spectral function from tau decays, we determine the lowest spectral moments of the left-right correlator and extract dynamical information on order parameters of the QCD chiral symmetry breaking. Uncertainties associated with violations of quark-hadron duality are estimated from the data, imposing all known short-distance constraints on a resonance-based parametrization. Employing proper pinched weight functions, we obtain an accurate determination of the effective chiral couplings L10 and C87 and the dimension-six and -eight contributions in the Operator Product Expansion.

   hep-phNucl.Part.Phys.Proc.(2016)·0 citations
8. 08*

   Flavors of Supersymmetry Beyond Vanilla

   Jared A. Evans🇺🇸

   This review surveys the territory of supersymmetry beyond the vanilla MSSM. With a viewpoint guided by electroweak naturalness, the review focuses on constructions that weaken or bypass current LHC constraints. Models of SUSY containing Dirac gluinos, compressed spectra, flavor-violating squarks, R-parity violation, stealth sectors, exotic detector objects, and more are discussed. In addition to presenting ways of hiding SUSY, these models highlight a few opportunities to improve LHC coverage.

   hep-ph5 citations
9. 09*

   Discovery potential for the neutral charmoniumlike $Z^0(4200)$ by $\bar{p}p$ annihilation

   Xiao-Yun Wang🇨🇳 · Xu-Rong Chen🇨🇳

   Inspired by the observation of charmoniumlike $Z(4200)$, we explore the discovery potential of the neutral $Z^0(4200)$ production by antiproton-proton annihilation with an effective Lagrangian approach. By investigating the $\bar{p}p\to J/\psi {\pi }^0$ process including the $Z^0(4200)$ signal and background contributions, it is found that the center of mass energy $E_{c.m.}\simeq 4.0-4.5$ GeV is the best energy window for searching the neutral $Z^0(4200)$, where the signal can be clearly distinguished from background. The relevant calculations is not only helpful to search for the neutral $Z^0(4200)$ in the future experiment, but also will promote the understanding the nature and production mechanism of neutral $Z^0(4200)$ better.

   hep-phAdv.High Energy Phys.(2015)·7 citations
10. 10*

    Appearance of novel modes of $\bar{D}$ mesons in the Dual Chiral Density Wave

    Daiki Suenaga🇯🇵 · Masayasu Harada🇯🇵

    We calculate dispersion relations for $\bar{D}(0^{-})$, ${\bar{D}}^{\ast }(1^{-})$, ${\bar{D}}_0^{\ast }(0^{+})$ and ${\bar{D}}_1(1^{+})$ mesons in the Dual Chiral Density Wave (DCDW) where the chiral symmetry is spontaneously broken by inhomogeneous chiral condensate. Employing the Bloch's theorem, we show that all the modes have opposite group velocity to the momentum in the low-momentum region and the energy is minimized at non-zero momentum. Furthermore, the magnitude of momentum which realizes the minimum energy is equal to the wave number of the density wave.

    hep-phnucl-thPRD(2016)·14 citations
11. 11*

    On Extraction of Chemical Potentials of Quarks from Particle Transverse Momentum Spectra in High Energy Collisions

    Hong Zhao🇨🇳 · Fu-Hu Liu🇨🇳

    We present two methods to extract the chemical potentials of quarks in high energy collisions. The first method is based on the ratios of negatively/positively charged particles, and the temperatures extracted from the transverse momentum spectra of related hadrons are needed. The second method is based on the chemical potentials of some particles, and we also need the transverse momentum spectra of related hadrons. To extract the quark chemical potentials, we would like to propose experimental collaborations to measure simultaneously not only the transverse momentum spectra of anti-p, p, K^-, K^+, pion^-, and pion^+, but also those of D^-, D^+, B^-, and B^+ (even those of Delta^++, Delta^-, and Omega^-) in high energy nuclear collisions

    hep-phhep-exnucl-exnucl-thAdv.High Energy Phys.(2015)·9 citations
12. 12*

    Flavor anomalies at the LHC and the R-parity violating supersymmetric model extended with vectorlike particles

    Weicong Huang🇨🇳 · Yi-Lei Tang🇨🇳

    In this paper, we consider a solution to explain the three discrepancies with the standard model (SM) predictions in flavor observables, i.e. anomalies in $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ and $R_K=\mathcal{B}(B\to K{\mu }^{+}{\mu }^{-})/\mathcal{B}(B\to K{e}^{+}{e}^{-})$ at the LHCb and an excess in $h\to \mu \tau$ at the CMS in the context of R-parity violating (RPV) supersymmetry. We demonstrate that these anomalies can be explained within a unified framework: the minimal supersymmetry model (MSSM) extended with $5+\overline{5}$ vectorlike (VL) particles. The new trilinear RPV couplings involving VL particles in our model can solve the $b\to s$ anomalies , and the mixing between the SM-like Higgs boson and the VL sneutrino can yield the extra $h\to \mu \tau$ decay mode.

    hep-phPRD(2015)·21 citations
13. 13*

    Strong $D_s^{\ast }{D}_s{\eta }^{(\prime )}$ and $B_s^{\ast }{B}_s{\eta }^{(\prime )}$ vertices from QCD light-cone sum rules

    S. S. Agaev🇦🇿 · K. Azizi🇹🇷 · H. Sundu🇹🇷

    The strong $D_s^{\ast }{D}_s{\eta }^{(\prime )}$ and $B_s^{\ast }{B}_s{\eta }^{(\prime )}$ vertices are studied and the relevant couplings are calculated in the context of the light-cone QCD sum rule method with twist-4 accuracy by including the next-to-leading order corrections. In the analysis, both the quark and gluon components of the $\eta$ and ${\eta }^{\prime }$ mesons and the axial anomaly corrected higher twist distributions are included.

    hep-phPRD(2015)·13 citations
14. 14*

    Weak charged and neutral current induced one pion production off the nucleon

    M. Rafi Alam🇮🇳 · M. Sajjad Athar🇮🇳 · S. Chauhan🇮🇳 · S. K. Singh🇮🇳

    We present a study of neutrino/antineutrino induced charged and neutral current single pion production off the nucleon. For this, we have considered $P_{33}(1232)$ resonance, non-resonant background terms, other higher resonances like $P_{11}(1440)$, $S_{11}(1535)$, $D_{13}(1520)$, $S_{11}(1650)$ and $P_{13}(1720)$. For the non-resonant background terms a microscopic approach based on SU(2) non-linear sigma model has been used. The vector form factors for the resonances are obtained by using the relationship between the electromagnetic resonance form factors and helicity amplitudes provided by MAID. Axial coupling $C_5^A(0)$ in the case of $P_{33}(1232)$ resonance is obtained by fitting the ANL and BNL $\nu$-deuteron reanalyzed scattering data. The results are presented with and without deuteron effect for the total scattering cross sections for all possible channels viz. ${\nu }_l({\bar{\nu }}_l)+N\to l^{-}(l^{+})+N^{\prime }+{\pi }^i$; ${\nu }_l({\bar{\nu }}_l)+N\to {\nu }_l({\bar{\nu }}_l)+N^{\prime }+{\pi }^i$, where $N,N^{\prime }=p,n$, ${\pi }^i={\pi }^{\pm }$ or ${\pi }^0$ and $l=e,\mu$.

    hep-phIJMPE(2016)·45 citations
15. 15*

    Dark Matter at the LHC and IceCube - a Simplified Model Interpretation

    Jan Heisig🇩🇪 · Mathieu Pellen🇩🇪

    We present an interpretation of searches for Dark Matter in a simplified model approach. Considering Majorana fermion Dark Matter and a neutral vector mediator with axial-vector interactions we explore mono-jet searches at the LHC and searches for neutrinos from Dark Matter annihilation in the Sun at IceCube and place new limits on model parameter space. Further, we compare the simplified model with its effective field theory approximation and discuss the validity of the latter one.

    hep-ph0 citations
16. 16*

    Higgs and flavour as doors to new physics

    Filippo Sala🇫🇷

    A natural solution to the hierarchy problem of the Fermi scale motivates signals of New Physics at current and near future experiments. After a critical synthesis of this general motivation, we concentrate our attention on the interplay between LHC searches for new resonances, and precision measurements of both Higgs couplings and flavour violating observables. We do so for i) the Higgs sectors of the NMSSM and MSSM, as paradigmatic examples of theories providing extra scalars, and for ii) CKM-like flavour symmetries, with a focus on U(2)^3. This article is mainly based on several papers by the author, but it also reviews other recent related results. Its goal is to provide a synthetic - yet comprehensive orientation on these subjects, at the dawn of several (ATLAS and CMS, LHCb, NA62 etc.) coming experimental results.

    hep-phhep-exEur.Phys.J.Plus(2016)·7 citations
17. 17*

    Complex-mass definition and the structure of unstable particle's propagator

    Vladimir Kuksa🇷🇺

    The propagators of unstable particles are considered in the framework of the convolution representation. Spectral function was found for a special case when the propagator of scalar unstable particle has Breight-Wigner form. The expressions for the dressed propagators of unstable vector and spinor fields are derived in an analytical way for this case. We got the propagators in modified Breit-Wigner forms which correspond to the complex-mass definition.

    hep-phAdv.High Energy Phys.(2015)·8 citations
18. 18*

    The inverse problem for Schwinger pair production

    Florian Hebenstreit🇨🇭

    The production of electron-positron pairs in time-dependent electric fields (Schwinger mechanism) depends non-linearly on the applied field profile. Accordingly, the resulting momentum spectrum is extremely sensitive to small variations of the field parameters. Owing to this non-linear dependence it is so far unpredictable how to choose a field configuration such that a predetermined momentum distribution is generated. We show that quantum kinetic theory along with optimal control theory can be used to approximately solve this inverse problem for Schwinger pair production. We exemplify this by studying the superposition of a small number of harmonic components resulting in predetermined signatures in the asymptotic momentum spectrum. In the long run, our results could facilitate the observation of this yet unobserved pair production mechanism in quantum electrodynamics by providing suggestions for tailored field configurations.

    hep-phquant-phPLB(2016)·16 citations
19. 19*

    Evidence of sub-nucleonic degrees of freedom in J/$\psi$ photoproduction in ultraperipheral collisions at the CERN Large Hadron Collider

    E. Andrade-II🇧🇷 · I. González🇧🇷 · A. Deppman🇧🇷 · C. A. Bertulani🇺🇸

    We present calculations for the incoherent photoproduction of J/$\psi$ vector mesons in ultra-peripheral heavy ion collisions (UPC) in terms of hadronic interactions. This study was carried out using the recently developed Monte Carlo model CRISP extended to include UPCs at LHC energies. A careful study of re-scattering and destruction of the J/$\psi$ particles is presented for PbPb collisions at $\sqrt{s_{NN}}=2.76$ TeV. We have also compared our method to AuAu collisions at $\sqrt{s_{NN}}=200$ GeV measured at RHIC.

    hep-phnucl-thPRC(2015)·9 citations
20. 20*

    Earth's Stopping Effect in Directional Dark Matter Detectors

    Chris Kouvaris🇩🇰

    We explore the stopping effect that results from interactions between dark matter and nuclei as the dark matter particles travel undergound towards the detector. Although this effect is negligible for heavy dark matter particles, there is parameter phase space where the underground interactions of the dark matter particles with the nuclei can create observable differences in the spectrum. Dark matter particles that arrive on the detector from below can have less energy from the ones arriving from above. These differences can be potentially detectable by upcoming directional detectors. This can unveil a large amount of information regarding the type and strength of interactions between nuclei and light dark matter candidates.

    hep-phPRD(2016)·22 citations
21. 21*

    Debye screening mass of hot Yang-Mills theory to three-loop order

    Ioan Ghisoiu🇫🇮 · Jan Moller🇩🇪 · York Schroder🇨🇱

    Building upon our earlier work, we compute a Debye mass of finite-temperature Yang-Mills theory to three-loop order. As an application, we determine a $g^7$ contribution to the thermodynamic pressure of hot QCD.

    hep-phhep-latnucl-thJHEP(2015)·39 citations
22. 22*

    Is the proton radius puzzle evidence of extra dimensions?

    F. Dahia🇧🇷 · A. S. Lemos🇧🇷

    The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron-proton interaction. The proton's new size was extracted from the 2S-2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon-proton gravitational interaction is stronger than the electron-proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon-proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between 2S and 2P states. In this scenario, the gravitational energy depends on the higher-dimensional Planck mass and indirectly on the brane thickness. Studying the behavior of the gravitational energy with respect to the brane thickness in a realistic range, we find constraints for the fundamental Planck mass that solve the proton radius puzzle and are consistent with previous experimental bounds.

    hep-phgr-qchep-thphysics.atom-phEPJC(2016)·20 citations
23. 23*

    A Precision Determination of the CKM Element |Vcb| and a Review of the Status of Inclusive |Vub|

    Kristopher J. Healey🇮🇹

    In these proceedings for CIPANP2015 we present a brief overview of the current status of the theoretical approaches used by our group for the extraction of $|V_{cb}|$ and $|V_{ub}|$ through inclusive semi-leptonic $B$ decays. We discuss the calculations and implications of the recent perturbative corrections to power-suppressed contributions for $|V_{cb}|$, and present an overview of the major sources of theoretical uncertainty for $|V_{ub}|$.

    hep-ph2 citations
24. 24*

    Electro-weak $\pi \pi$ form factor and $\pi \pi$ scattering: towards a phenomenological tool

    M. R. Robilotta🇧🇷

    The weak two-pion form factor $F_V^{\pi \pi }$ is described as the product of a weak kernel ${\mathcal{K}}_{\mathcal{W}}$ by a strong function ${\Theta }_{\pi \pi }^P$, determined directly from $\pi \pi$ scattering data. As the latter accounts at once for all effects associated with resonances, intermediate $K\bar{K}$ loops, and other possible inelasticities present in $\pi \pi$ scattering, the need of modeling is restricted to ${\mathcal{K}}_{\mathcal{W}}$ only. The procedure proposed allows one to asses the weak kernel directly, which has a dominant cut beginning at the $K\bar{K}$ threshold. Even the simplest vector-meson-dominance choice for ${\mathcal{K}}_{\mathcal{W}}$ already yields a good qualitative description of $F_V^{\pi \pi }$. The energy sector below $0.8$ GeV is quite well reproduced when a precise theoretical chiral perturbation $\pi \pi$ amplitude is used as input, together with the single free parameter $F_V{G}_V/F^2=1.20$. The inclusion of kaon loops, along well established lines and using few parameters, produces a good description of the form factor in the entire energy range allowed by $\tau$ decays. This indicates that the replacement of modeling by direct empirical scattering information can also be useful in the construction of theoretical tools to be used in analysesof hadronic heavy meson decay data.

    hep-ph0 citations
25. 25*

    Beyond the CMSSM without an Accelerator: Proton Decay and Direct Dark Matter Detection

    John Ellis🇬🇧 · Jason L. Evans🇺🇸 · Feng Luo🇨🇭 · Natsumi Nagata🇺🇸 · Keith A. Olive🇺🇸 · Pearl Sandick🇺🇸

    We consider two potential non-accelerator signatures of generalizations of the well-studied constrained minimal supersymmetric standard model (CMSSM). In one generalization, the universality constraints on soft supersymmetry-breaking parameters are applied at some input scale $M_{in}$ below the grand unification (GUT) scale $M_{GUT}$, a scenario referred to as `sub-GUT'. The other generalization we consider is to retain GUT-scale universality for the squark and slepton masses, but to relax universality for the soft supersymmetry-breaking contributions to the masses of the Higgs doublets. As with other CMSSM-like models, the measured Higgs mass requires supersymmetric particle masses near or beyond the TeV scale. Because of these rather heavy sparticle masses, the embedding of these CMSSM-like models in a minimal SU(5) model of grand unification can yield a proton lifetime consistent with current experimental limits, and may be accessible in existing and future proton decay experiments. Another possible signature of these CMSSM-like models is direct detection of supersymmetric dark matter. The direct dark matter scattering rate is typically below the reach of the LUX-ZEPLIN (LZ) experiment if $M_{in}$ is close to $M_{GUT}$, but may lie within its reach if $M_{in}\lesssim 10^{11}$ GeV. Likewise, generalizing the CMSSM to allow non-universal supersymmetry-breaking contributions to the Higgs offers extensive possibilities for models within reach of the LZ experiment that have long proton lifetimes.

    hep-phastro-ph.COEPJC(2016)·80 citations
26. 26*

    Self-similarity of proton spin and z-scaling

    M.Tokarev (1)🇷🇺 · I.Zborovsky (2) ((1) Veksler and Baldin Laboratory of High Energy Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia, (2) Nuclear Physics Institute, Academy of Sciences of the Czech Republic, Rez, Czech Republic)🇨🇿

    The concept of z-scaling previously developed for analysis of inclusive reactions in proton-proton collisions is applied for description of processes with polarized particles. Hypothesis of self-similarity of the proton spin structure is discussed. The possibility of extracting information on spin-dependent fractal dimensions of hadrons and fragmentation process from the cross sections and asymmetries is justified. The double longitudinal spin asymmetry A_{LL} of jet and pi0-meson production and the coefficient of polarization transfer D_{LL} measured in proton-proton collisions at sqrt s = 200 GeV at RHIC are analyzed in the framework of z-scaling. The spin-dependent fractal dimension of proton is estimated.

    hep-phJ.Phys.Conf.Ser.(2016)·2 citations
27. 27*

    A Vision of Nuclear and Particle Physics

    Hugh E. Montgomery🇺🇸

    This paper will consist of a selected, personal view of some of the issues associated with the intersections of nuclear and particle physics. As well as touching on the recent developments we will attempt to look at how those aspects of the subject might evolve over the next few years.

    ↳ hep-exhep-ph1 citation
28. 28*

    Limiting SUSY compressed spectra scenarios

    A. Nelson🇺🇸 · P. Tanedo🇺🇸 · D. Whiteson🇺🇸

    Typical searches for supersymmetry cannot test models in which the two lightest particles have a small ("compressed") mass splitting, due to the small momentum of the particles produced in the decay of the second-to-lightest particle. However, datasets with large missing transverse momentum ($E_{\mathrm{T}}^{\mathrm{miss}}$) can generically search for invisible particle production and therefore provide constraints on such models. We apply data from the ATLAS mono-jet (jet+$E_{\mathrm{T}}^{\mathrm{miss}}$) and vector-boson-fusion (forward jets and $E_{\mathrm{T}}^{\mathrm{miss}}$) searches to such models. The two datasets have complementary sensitivity, but in all cases experimental limits are at least five times weaker than theoretical predictions.

    ↳ hep-exhep-phPRD(2016)·6 citations
29. 29*

    Renormalization-Group Evolution and Nonperturbative Behavior of Chiral Gauge Theories with Fermions in Higher-Dimensional Representations

    Yan-Liang Shi🇺🇸 · Robert Shrock🇺🇸

    We study the ultraviolet to infrared evolution and nonperturbative behavior of a simple set of asymptotically free chiral gauge theories with an SU($N$) gauge group and an anomaly-free set of $n_{S_k}$ copies of chiral fermions transforming as the symmetric rank-$k$ tensor representation, $S_k$, and $n_{{\bar{A}}_{\ell }}$ copies of fermions transforming according to the conjugate antisymmetric rank-$\ell$ tensor representation, ${\bar{A}}_{\ell }$, of this group with $k,\ell \ge 2$. As part of our study, we prove a general theorem guaranteeing that a low-energy effective theory resulting from the dynamical breaking of an anomaly-free chiral gauge theory is also anomaly-free. We analyze the theories with $k=\ell =2$ in detail and show that there are only a finite number of these. Depending on the specific theory, the ultraviolet to infrared evolution may lead to a non-Abelian Coulomb phase, or may involve confinement with massless composite fermions, or fermion condensation with dynamical gauge and global symmetry breaking. We show that $S_k{\bar{A}}_k$ chiral gauge theories with $k\ge 3$ are not asymptotically free. We also analyze theories with fermions in $S_k$ and ${\bar{A}}_{\ell }$ representations of SU($N$) with $k\ne \ell$ and $k,\ell \ge 2$.

    ↳ hep-thhep-phPRD(2015)·27 citations
30. 30*

    Nucleon Resonance Transition Formfactors

    I. G. Aznauryan🇦🇲 · V. D. Burkert🇺🇸 · V. I. Mokeev🇺🇸

    We discuss recent results from CLAS on electromagnetic resonance transition amplitudes and their dependence on the distance scale ($Q^2$). From the comparison of these results with most advanced theoretical calculations within QCD-based approaches there is clear evidence that meson-baryon contributions are present and important at large distances, i.e. small $Q^2$, and that quark core contributions dominate the short distance behavior.

    ↳ nucl-exhep-lathep-phnucl-th1 citation
31. 31*

    A GeV source in the direction of Supernova Remnant CTB 37B

    Yu-Liang Xin🇨🇳 · Yun-Feng Liang🇨🇳 · Xiang Li🇨🇳 · Qiang Yuan🇨🇳 · Si-Ming Liu🇨🇳 · Da-Ming Wei🇨🇳

    Supernova remnants (SNRs) are the most attractive candidates for the acceleration sites of Galactic cosmic rays. We report the detection of GeV $\gamma$-ray emission with the Pass 8 events recorded by Fermi Large Area Telescope (Fermi-LAT) in the vicinity of the shell type SNR CTB 37B that is likely associated with the TeV $\gamma -$ray source HESS J1713-381. The photon spectrum of CTB 37B is consistent with a power-law with an index of $1.89\pm 0.08$ in the energy range of $0.5-500$ GeV, and the measured flux connects smoothly with that of HESS J1713-381 at a few hundred GeV. No significant spatial extension and time variation are detected. The multi-wavelength data can be well fitted with either a leptonic model or a hadronic one. However, parameters of both models suggest more efficient particle acceleration than typical SNRs. Meanwhile, the X-ray and $\gamma$-ray spectral properties of CTB 37B show that it is an interesting source bridging young SNRs dominated by non-thermal emission and old SNRs interacting with molecular clouds.

    ↳ astro-ph.HEhep-phApJ(2016)·18 citations
32. 32*

    A study of transverse momentum distributions of jets produced in p-p, p-\bar p, d-Au, Au-Au, and Pb-Pb collisions at high energies

    Hua-Rong Wei🇨🇳 · Fu-Hu Liu🇨🇳

    The transverse momentum distributions of jets produced in p-p, p-\bar p, d-Au, Au-Au, and Pb-Pb collisions at high energies with different selected conditions are analyzed by using a multi-source thermal model. The multi-component (mostly two-component) Erlang distribution used in our description is in good agreement with the experimental data measured by the STAR, D0, CDF II, ALICE, ATLAS, and CMS Collaborations. Related parameters are extracted from the transverse momentum distributions and some information on different interacting systems are obtained. In the two-component Erlang distribution, the first component has usually two or more sources which are contributed by strong scattering interactions between two quarks or more quarks and gluons, while the second component has mostly two sources which are contributed by harder head-on scattering between two quarks.

    ↳ nucl-exhep-exhep-phnucl-thAdv.High Energy Phys.(2015)·1 citation
33. 33*

    Transverse momentum and pseudorapidity distributions of final-state particles and spatial structure pictures of interacting system in p-Pb collisions at \sqrt{s_{NN}}=5.02 TeV

    Fu-Hu Liu🇨🇳 · Hua-Rong Wei🇨🇳 · Roy A. Lacey🇺🇸

    The transverse momentum and pseudorapidity distributions of final-state particles produced in proton-lead (p-Pb) collisions at center-of-mass energy per nucleon pair \sqrt{s_{NN}}=5.02 TeV are studied in the framework of a multisource thermal model. Experimental results measured by the ALICE and CMS Collaborations are described by the Tsallis transverse momentum distribution and the two-cylinder pseudorapidity distribution. Based on the parameter values extracted from the transverse momentum and pseudorapidity distributions, some other quantities are extracted. Then, the structure pictures of interacting system at the stage of kinetic freeze-out in some spaces are obtained.

    ↳ nucl-thhep-exhep-phnucl-exEPJA(2015)·4 citations
34. 34*

    On pseudorapidity distribution and speed of sound in high energy heavy ion collisions based on a new revised Landau hydrodynamic model

    Li-Na Gao🇨🇳 · Fu-Hu Liu🇨🇳

    We propose a new revised Landau hydrodynamic model to study systematically the pseudorapidity distributions of charged particles produced in heavy ion collisions over an energy range from a few GeV to a few TeV per nucleon pair. The interacting system is divided into three sources namely the central, target, and projectile sources respectively. The large central source is described by the Landau hydrodynamic model and further revised by the contributions of the small target/projectile sources. In the calculation, to avoid the errors caused by an unapt conversion or non-division, the rapidity and pseudorapidity distributions are obtained respectively. The modeling results are in agreement with the available experimental data at relativistic heavy ion collider (RHIC), large hadron collider (LHC), and other energies for different centralities. The value of square speed of sound parameter in different collisions has been extracted by us from the widths of rapidity distributions. Our results show that, in heavy ion collisions at RHIC and LHC energies, the central source undergoes through a phase transition from hadronic gas to quark-gluon plasma (QGP) liquid phase; meanwhile, the target/projectile sources remain in the state of hadronic gas. The present work confirms that the QGP is of liquid type rather than that of a gas. The whole region of participants undergoes through a mixed phase consisting of a large quantity of (>90%) QGP liquid and a small quantity of (<10%) hadronic gas.

    ↳ nucl-exhep-exhep-phnucl-thAdv.High Energy Phys.(2015)·18 citations
35. 35*

    On Productions of Net-baryons in Central Au-Au Collisions at RHIC Energies

    Ya-Hui Chen🇨🇳 · Guo-Xing Zhang🇨🇳 · Fu-Hu Liu🇨🇳

    The transverse momentum and rapidity distributions of net-baryons (baryons minus anti-baryons) produced in central gold-gold (Au-Au) collisions at 62.4 and 200 GeV are analyzed in the framework of a multisource thermal model. Each source in the model is described by the Tsallis statistics to extract the effective temperature and entropy index from the transverse momentum distribution. The two parameters are used as input to describe the rapidity distribution and to extract the rapidity shift and contribution ratio. Then, the four types of parameters are used to structure some scatter plots of the considered particles in some three-dimensional (3D) spaces at the stage of kinetic freeze-out, which are expected to show different characteristics for different particles and processes. The related methodology can be used in the analyzes of particle production and event holography, which are useful for us to better understand the interacting mechanisms.

    ↳ nucl-thhep-exhep-phnucl-exAdv.High Energy Phys.(2015)·5 citations
36. 36*

    Early-time cosmological solutions in scalar-Gauss-Bonnet theory

    Panagiota Kanti🇬🇷

    We consider a gravitational theory that contains the Einstein term, a scalar field and the quadratic Gauss-Bonnet term. We focus on the early-universe dynamics, and demonstrate that the Ricci scalar does not affect the cosmological solutions at early times, when the curvature is strong. We then consider a pure scalar-GB theory with a quadratic coupling function: for a negative coupling parameter, we obtain solutions that contain always an inflationary, de Sitter phase, while for a positive coupling function, we find instead expanding singularity-free solutions.

    ↳ hep-thastro-ph.COgr-qchep-ph3 citations
37. 37*

    Prospects for Higgs properties measurements at future colliders

    Flavia de Almeida Dias🇬🇧

    The LHC Run-1 was very successful and included the discovery of a new particle with mass of about 125 GeV compatible with the Higgs boson predicted by the Standard Model. The prospects for Higgs physics at the high-luminosity LHC and at future colliders are presented. In particular, the ultimate precision attainable for the couplings measurements of the 125 GeV particle with elementary fermions and bosons is discussed along with prospects for self-coupling measurements, for the ATLAS and CMS detectors at the upgraded LHC.

    ↳ hep-exhep-ph2 citations
38. 38*

    The Heterotic Superpotential and Moduli

    Xenia de la Ossa🇬🇧 · Edward Hardy🇮🇹 · Eirik Eik Svanes🇫🇷

    We study the four-dimensional effective theory arising from ten-dimensional heterotic supergravity compactified on manifolds with torsion. In particular, given the heterotic superpotential appropriately corrected at $\mathcal{O}({\alpha }^{\prime })$ to account for the Green-Schwarz anomaly cancellation mechanism, we investigate properties of four-dimensional Minkowski vacua of this theory. Considering the restrictions arising from F-terms and D-terms we identify the infinitesimal massless moduli space of the theory. We show that it agrees with the results that have recently been obtained from a ten-dimensional perspective where supersymmetric Minkowski solutions including the Bianchi identity correspond to an integrable holomorphic structure, with infinitesimal moduli calculated by its first cohomology. As has recently been noted, interplay of complex structure and bundle deformations through holomorphic and anomaly constraints can lead to fewer moduli than may have been expected. We derive a relation between the number of complex structure and bundle moduli removed from the low energy theory in this way, and give conditions for there to be no complex structure moduli or bundle moduli remaining in the low energy theory. The link between Yukawa couplings and obstruction theory is also briefly discussed.

    ↳ hep-thhep-phmath.DGJHEP(2016)·42 citations
39. 39*

    Neutrino mass hierarchy determination at reactor antineutrino experiments

    Guang Yang🇺🇸

    After the neutrino mixing angle ${\theta }_{13}$ has been precisely measured by the reactor antineutrino experiments, one of the most important open questions left in neutrino physics is the neutrino mass hierarchy. Jiangmen Underground Neutrino Observatory (JUNO) is designed to determine the neutrino mass hierarchy (MH) without exploring the matter effect. The JUNO site location is optimized to have the best sensitivity for the mass hierarchy determination. JUNO will employ a 20 kton liquid scintillator detector located in a laboratory 700 meters underground. The excellent energy resolution and PMT coverage will give us an unprecedented opportunity to reach a 3-4 $\sigma$ precision. In this paper, the JUNO detector design and simulation work will be presented. Also, RENO-50, another medium distance reactor antineutrino experiment, will do a similar measurement. With the efforts of these experiments, it is very likely that the neutrino mass hierarchy will be determined in the next 10 years.

    ↳ physics.ins-dethep-exhep-ph5 citations
40. 40*

    How strange is pion electroproduction?

    Mikhail Gorchtein🇩🇪 · Hubert Spiesberger🇩🇪 · Xilin Zhang🇺🇸

    We consider pion production in parity-violating electron scattering (PVES) in the presence of nucleon strangeness in the framework of partial wave analysis with unitarity. Using the experimental bounds on the strange form factors obtained in elastic PVES, we study the sensitivity of the parity-violating asymmetry to strange nucleon form factors. For forward kinematics and electron energies above 1 GeV, we observe that this sensitivity may reach about 20\% in the threshold region. With parity-violating asymmetries being as large as tens p.p.m., this study suggests that threshold pion production in PVES can be used as a promising way to better constrain strangeness contributions. Using this model for the neutral current pion production, we update the estimate for the dispersive $\gamma Z$-box correction to the weak charge of the proton. In the kinematics of the Qweak experiment, our new prediction reads Re${\square }_{\gamma Z}^V(E=1.165\mathrm{GeV})=(5.58\pm 1.41)\times 10^{-3}$, an improvement over the previous uncertainty estimate of $\pm 2.0\times 10^{-3}$. Our new prediction in the kinematics of the upcoming MESA/P2 experiment reads Re${\square }_{\gamma Z}^V(E=0.155\mathrm{GeV})=(1.1\pm 0.2)\times 10^{-3}$.

    ↳ nucl-thhep-phnucl-exPLB(2016)·12 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.