Thu·Jan 24, 2019Thursday·January 24, 2019

1. 01*

   The two-loop corrections to lepton MDMs and EDMs in the EBLMSSM

   Xing-Xing Dong🇨🇳 · Shu-Min Zhao🇨🇳 · Hai-Bin Zhang🇨🇳 · Tai-Fu Feng🇨🇳

   Extending BLMSSM with exotic Higgs superfields $({\Phi }_{NL},{\phi }_{NL})$ and superfields ($Y,Y^{\prime }$), one obtains the new model called as EBLMSSM, where exotic leptons are heavy and have tree level couplings with SM lepton. In this model, some new parameters with CP-violating phases are considered, so there are new contributions to lepton anomalous magnetic dipole moments (MDMs) and electric dipole moments (EDMs). Therefore, we study the one-loop, two-loop Barr-Zee and two-loop Rainbow type corrections to lepton MDMs and EDMs in the EBLMSSM. Considering the constraints from the lightest CP-even Higgs mass and decays, we calculate the corresponding numerical results. In our used parameter space, the new physics contributions to lepton MDMs are large, which can remedy the deviation between the SM prediction and experimental result well. New introduced CP-violating phases also affect the lepton EDMs in a certain degree.

   hep-phJ.Phys.G(2020)·13 citations
2. 02*

   The EMC ratios of ${}^{4}He$, ${}^{3}He$ and ${}^{3}H$ nuclei in the $k_t$ factorization framework using the Kimber-Martin-Ryskin unintegrated parton distribution functions

   M. Modarres🇮🇷 · H. Hadian🇮🇷

   The unintegrated parton distribution functions (UPDFs) of ${}^{3}H$, ${}^{3}He$ and ${}^{4}He$ nuclei are generated to calculate their structure functions (SFs) in the $k_t$-factorization approach. The Kimber-Martin-Ryskin (KMR) formalisn is applied to evaluate the double-scale UPDFs of these nuclei from their single-scale parton distribution functions (PDFs), which can be obtained from the constituent quark exchange model (CQEM). Afterwards, these SFs are used to calculate the European Muon Collaboration (EMC) ratios of these nuclei. The resulting EMC ratios are then compared with the available experimental data and good agreement with data is achieved. In comparison with our previous EMC ratios, in which the conventional PDFs were used in the calculations, the accord of the present outcomes with experiment at the small $x$ region becomes impressive. Therefore, it can be concluded that the $k_t$ dependence of partons can reproduce the general form of the shadowing effect at the small $x$ values in above nuclei.

   hep-phNPA(2019)·8 citations
3. 03*

   Extracting the pomeron-pomeron-$f_2(1270)$ coupling in the $pp\to pp{\pi }^{+}{\pi }^{-}$ reaction through angular distributions of the pions

   Piotr Lebiedowicz🇵🇱 · Otto Nachtmann🇩🇪 · Antoni Szczurek🇵🇱

   We discuss how to extract the pomeron-pomeron-$f_2(1270)$ ($\mathbb{PP}{f}_2(1270)$) coupling within the tensor-pomeron model. The general $\mathbb{PP}{f}_2(1270)$ coupling is a combination of seven basic couplings (tensorial structures). To study these tensorial structures we propose to measure the central-exclusive production of a ${\pi }^{+}{\pi }^{-}$ pair in the invariant mass region of the $f_2(1270)$ meson. An analysis of angular distributions in the ${\pi }^{+}{\pi }^{-}$ rest system, using the Collins-Soper (CS) and the Gottfried-Jackson (GJ) frames, turns out to be particularly relevant for our purpose. For both frames the $\cos {\theta }_{{\pi }^{+}}$ and ${\varphi }_{{\pi }^{+}}$ distributions are discussed. We find that the azimuthal angle distributions in these frames are fairly sensitive to the choice of the $\mathbb{PP}{f}_2$ coupling. We show results for the resonance case alone as well as when the dipion continuum is included. We show the influence of the experimental cuts on the angular distributions in the context of dedicated experimental studies at RHIC and LHC energies. Absorption corrections are included for our final distributions.

   hep-phPRD(2020)·23 citations
4. 04*

   Predictive Scotogenic Model with Flavor Dependent Symmetry

   Zhi-Long Han🇨🇳 · Weijian Wang🇨🇳

   In this paper, we propose a viable approach to realise two texture-zeros in the scotogenic model with flavor dependent $U(1{)}_{B-2L_{\alpha }-L_{\beta }}$ gauge symmetry. These models are extended by two right-handed singlets $N_{Ri}$ and two inert scalar doublets ${\eta }_i$, which are odd under the dark $Z_2$ symmetry. Among all the six constructed textures, texture $A_1$ and $A_2$ are the only two allowed by current experimental limits. Then choosing texture $A_1$ derived from $U(1{)}_{B-2L_e-L_{\tau }}$, we perform a detail analysis on the corresponding phenomenology such as predictions of neutrino mixing parameters, lepton flavor violation, dark matter and collider signatures. One distinct nature of such model is that the structure of Yukawa coupling $\bar{L}\tilde{\eta }{N}_R$ is fixed by neutrino oscillation data, and can be further tested by measuring the branching ratios of charged scalars ${\eta }_{1,2}^{\pm }$.

   hep-phEPJC(2019)·17 citations
5. 05*

   FIRE6: Feynman Integral REduction with Modular Arithmetic

   A.V. Smirnov🇷🇺 · F.S. Chukharev🇷🇺

   FIRE is a program performing reduction of Feynman integrals to master integrals. The C++ version of FIRE was presented in 2014. There have been multiple changes and upgrades since then including the possibility to use multiple computers for one reduction task and to perform reduction with modular arithmetic. The goal of this paper is to present the current version of FIRE.

   hep-phComput.Phys.Commun.(2020)·512 citations
6. 06*

   Transport properties from Charm to Bottom: $p_T$ suppression, anisotropic flow $v_n$ and their correlations to the bulk dynamics

   S. Plumari🇮🇹 · G. Coci🇮🇹 · S.K. Das🇮🇹 · V. Minissale🇮🇹 · V. Greco🇮🇹

   We study the propagation of heavy quarks (HQs) in the quark-gluon plasma (QGP) by means of a relativistic Boltzmann transport (RBT) approach. The non-perturbative interaction between heavy quarks and light quarks is described by means of a quasi-particle approach able to describe simultaneously the experimental data for the nuclear suppression factor $R_{\mathrm{AA}}$ and the elliptic flow $v_2(p_T)$ of D mesons from RHIC to LHC energies. In the same framework we predict the B meson nuclear modification factor at LHC. Finally, we discuss the relevance of initial state fluctuations that allows to extend the analysis to high order anisotropic flows $v_n(p_T)$ as well as to investigate the role of QCD interaction in developing correlations between the light and the heavy flavour anisotropic flows.

   hep-phnucl-thNPA(2019)·3 citations
7. 07*

   Very special relativity induced phase in neutrino oscillation

   Alekha C. Nayak🇮🇳

   In Very Special Relativity (VSR), the neutrino mass term is coupled with the VSR preferred axis, and hence Lorentz violating in nature. Beyond standard model physics predicts neutrino magnetic moment which is linearly proportional to the mass eigenstates of the neutrinos. We report an additive kinematic phase in the neutrino flavor oscillation due to the neutrino magnetic moment in the VSR framework. This phase is proportional to the coupling between the VSR preferred axis with the external magnetic field as well as the spin of the neutrino. Furthermore, we predict time variation in the neutrino oscillation with a period of one sidereal day.

   hep-phInt.J.Mod.Phys.A(2021)·1 citation
8. 08*

   Higher-order corrections to heavy-quark jet quenching

   Boris Blok🇮🇱 · Konrad Tywoniuk🇳🇴

   We calculate higher-order corrections to the quenching factor of heavy-quark jets due to hard, in-medium splittings in the framework of the BDMPS-Z formalism. These corrections turn out to be sensitive to a single mass-scale $m_{\ast }=(\hat{q}L{)}^{1/2}$, where $\hat{q}$ is the medium transport coefficient and $L$ the path length, and allow to draw a distinction between the way light, with $m<m_{\ast }$ (in contrast to massless $m=0$), and genuinely heavy, with $m>m_{\ast }$, quark jets are quenched in the medium. We show that the corrections to the quenching factor at high energies are double-logarithmic and qualitatively of the same order as for the massless quark jet.

   hep-phnucl-thEPJC(2019)·11 citations
9. 09*

   Seesaw mirroring between light and heavy Majorana neutrinos with the help of the $S_3^{}$ reflection symmetry

   Zhi-zhong Xing🇨🇳 · Di Zhang🇨🇳

   In the canonical seesaw mechanism we require the relevant neutrino mass terms to be invariant under the $S_3^{}$ charge-conjugation transformations of left- and right-handed neutrino fields. Then both the Dirac mass matrix $M_{\mathrm{D}}^{}$ and the right-handed neutrino mass matrix $M_{\mathrm{R}}^{}$ are well constrained, so is the effective light Majorana neutrino mass matrix $M_{\nu }^{}$ via the seesaw formula. We find that these mass matrices can be classified into 22 categories, among which some textures respect the well-known $\mu$-$\tau$ permutation or reflection symmetry and flavor democracy. It is also found that there exist remarkable structural equalities or similarities between $M_{\nu }^{}$ and $M_{\mathrm{R}}^{}$, reflecting a seesaw mirroring relationship between light and heavy Majorana neutrinos. We calculate the corresponding light neutrino masses and flavor mixing parameters as well as the CP-violating asymmetries in decays of the lightest heavy Majorana neutrino, and show that only the flavored leptogenesis mechanism is possible to work for three categories of $M_{\mathrm{D}}^{}$ and $M_{\mathrm{R}}^{}$ in the $S_3^{}$ reflection symmetry limit.

   hep-phhep-exJHEP(2019)·18 citations
10. 10*

    Flavor changing in the flipped trinification

    D. N. Dinh🇻🇳 · D. T. Huong🇻🇳 · N. T. Duy🇻🇳 · N. T. Nhuan🇻🇳 · L. D. Thien🇻🇳 · Phung Van Dong🇻🇳

    The flipped trinification, a framework for unifying the 3-3-1 and left-right symmetries, has recently been proposed in order to solve profound questions, the weak parity violation and the number of families, besides the implication for neutrino mass generation and dark matter stability. In this work, we argue that this gauge-completion naturally provides flavor-changing neutral currents in both quark and lepton sectors. The quark flavor changing happens at the tree-level due to the nonuniversal couplings of $Z_{L,R}^{\prime }$, while the lepton flavor changing $l\to l^{\prime }\gamma$ starts from the one loop level contributed significantly by the new charged currents of $Y_{L,R}$, which couple ordinary to exotic leptons. These effects disappear in the minimal left-right model, but are present in the framework characterizing a flipped trinification symmetry.

    hep-phPRD(2019)·16 citations
11. 11*

    Coherent photoproduction of $J/\psi$ in nucleus-nucleus collisions in the color dipole approach

    Agnieszka Łuszczak🇵🇱 · Wolfgang Schäfer🇵🇱

    We investigate the exclusive photoproduction of $J/\psi$-mesons in ultraperipheral heavy ion collisions in the color dipole approach. We first test a number of dipole cross sections fitted to inclusive $F_2$-data against the total cross section of exclusive $J/\psi$-production on the free nucleon. We then use the color-dipole formulation of Glauber-Gribov theory to calculate the diffractive amplitude on the nuclear target. The real part of the free nucleon amplitude is taken into account consistent with the rules of Glauber theory. We compare our results to recent published and preliminary data on exclusive $J/\psi$ corrections in ultraperipheral lead-lead collisions at $\sqrt{s_{NN}}=2.76\mathrm{TeV}$ and $\sqrt{s_{NN}}=5.02\mathrm{TeV}$. Especially at high $\gamma A$ energies there is room for additional shadowing corrections, corresponding to triple-Pomeron terms or shadowing from large mass diffraction.

    hep-phPRC(2019)·41 citations
12. 12*

    Matrix Element Method at NLO for (anti-)${\mathbf{k}}_{\mathbf{t}}$-jet algorithms

    Manfred Kraus🇩🇪 · Till Martini🇩🇪 · Peter Uwer🇩🇪

    In this article, we present a method to calculate a posteriori event weights at next-to-leading-order (NLO) QCD accuracy for a given jet event defined by the (anti-)$k_t$ algorithm relying on the conventional $2\to 1$ recombination. This is an important extension compared to existing Monte-Carlo tools which generate jet events together with the corresponding weight but do not allow one to calculate the weight for a given event. The method can be used to generate unweighted events distributed according to the fixed-order NLO cross section. In addition, the method allows one to calculate NLO accurate weights for events recorded by experiments. The potential of this ability is illustrated by applying the Matrix Element Method (MEM) to single top-quark events generated with POWHEG in combination with Pythia. For the first time, a systematic study of parton shower effects within the MEM is provided. The method is completely general and can be applied to arbitrary LHC processes.

    hep-phhep-exPRD(2019)·18 citations
13. 13*

    Confronting Scherk-Schwarz orbifold models with LHC data

    Dumitru Dan Smaranda🇬🇧 · David J Miller🇬🇧

    We will outline our recent efforts aimed at analysing a class of models known as orbifold GUTs and their phenomenology in a variety of minimal and non-minimal settings. We examine the minimal SU(5) models, rule them out, and proceed by extending them with an additional scalar field along with a gauge extension via SU(5)xU(1) models. We end up by commenting on the future improvements needed to more accurately handle exclusions along with tracing the U(1) gauge extensions to more complete 6D theories.

    hep-phPoS(2019)·0 citations
14. 14*

    The $O({\alpha }^2)$ Initial State QED Corrections to $e^{+}{e}^{-}$ Annihilation to a Neutral Vector Boson Revisited

    J. Blümlein🇩🇪 · A. De Freitas🇩🇪 · C.G. Raab🇦🇹 · K. Schönwald🇩🇪

    We calculate the non-singlet, the pure singlet contribution, and their interference term, at $O({\alpha }^2)$ due to electron-pair initial state radiation to $e^{+}{e}^{-}$ annihilation into a neutral vector boson in a direct analytic computation without any approximation. The correction is represented in terms of iterated incomplete elliptic integrals. Performing the limit $s\gg m_e^2$ we find discrepancies with the earlier results of Ref.~\cite{Berends:1987ab} and confirm results obtained in Ref.~\cite{Blumlein:2011mi} where the effective method of massive operator matrix elements has been used, which works for all but the power corrections in $m^2/s$. In this way, we also confirm the validity of the factorization of massive partons in the Drell-Yan process. We also add non-logarithmic terms at $O({\alpha }^2)$ which have not been considered in \cite{Berends:1987ab}. The corrections are of central importance for precision analyzes in $e^{+}{e}^{-}$ annihilation into ${\gamma }^{\ast }/Z^{\ast }$ at high luminosity.

    hep-phhep-exPLB(2019)·32 citations
15. 15*

    Improved bounds on ${\mathbb{Z}}_3$ singlet dark matter

    Andi Hektor🇪🇪 · Andrzej Hryczuk🇵🇱 · Kristjan Kannike🇪🇪

    We reconsider complex scalar singlet dark matter stabilised by a ${\mathbb{Z}}_3$ symmetry. We refine the stability bounds on the potential and use constraints from unitarity on scattering at finite energy to place a stronger lower limit on the direct detection cross section. In addition, we improve the treatment of the thermal freeze-out by including the evolution of the dark matter temperature and its feedback onto relic abundance. In the regions where the freeze-out is dominated by resonant or semi-annihilation, the dark matter decouples kinetically from the plasma very early, around the onset of the chemical decoupling. This results in a modification of the required coupling to the Higgs, which turns out to be at most few per cent in the semi-annihilation region, thus giving credence to the standard approach to the relic density calculation in this regime. In contrast, for dark matter mass just below the Higgs resonance, the modification of the Higgs invisible width and direct and indirect detection signals can be up to a factor $6.7$. The model is then currently allowed at $56.8$ GeV to $58.4$ GeV (depending on the details of early kinetic decoupling) $\lesssim M_S\lesssim 62.8$ GeV and at $M_S\gtrsim 122$ GeV if the freeze-out is dominated by semi-annihilation. We show that the whole large semi-annihilation region will be probed by the near-future measurements at the XENONnT experiment.

    hep-phJHEP(2019)·43 citations
16. 16*

    Heavy ion jet physics studies using precision jet substructure and quark-gluon jet classification

    Yang-Ting Chien🇺🇸

    In the first talk I discuss the usefulness of jet grooming for testing jet quenching mechanisms, and I present a calculation of soft-drop jet mass distribution in proton-proton and heavy ion collisions. In the second talk I discuss the comprehensive studies of quark and gluon jet substructure as a way to search for qualitatively new jet modification signatures. I emphasize the importance of precise understanding of jet substructure as well as powerful analysis tools in future heavy ion jet physics studies, with direct applications to hard probes using heavy flavors and hadronically-decaying electroweak bosons.

    hep-phhep-exnucl-exnucl-thPoS(2019)·1 citation
17. 17*

    Probing the high-x content of the nuclei in the fixed-target mode at the LHC

    A. Kusina🇵🇱 · C. Hadjidakis🇫🇷 · D. Kikola🇵🇱 · J.P. Lansberg🇫🇷 · L. Massacrier🇫🇷 · M.G. Echevarria🇮🇹 · I. Schienbein🇫🇷 · J. Seixas🇵🇹 · H.S. Shao🇫🇷 · A. Signori🇺🇸 · B. Trzeciak🇳🇱 · S.J. Brodsky🇺🇸 and 21 other authors

    Using the LHCb and ALICE detectors in the fixed-target mode at the LHC offers unprecedented possibilities to study the quark, gluon and heavy-quark content of the proton and nuclei in the poorly known region of the high-momentum fractions. We review our projections for studies of Drell-Yan, charm, beauty and quarkonium production with both detector set-ups used with various nuclear targets and the LHC proton beams. Based on this, we show the expected improvement in the determination of the quark, charm and gluon proton and nuclear PDFs as well as discuss the implication for a better understanding of the cold-nuclear-matter effects in hard-probe production in proton-nucleus collisions.

    ↳ hep-exhep-phPoS(2019)·3 citations
18. 18*

    The LHCSpin Project

    C.A. Aidala🇺🇸 · A. Bacchetta🇮🇹 · M. Boglione🇮🇹 · G. Bozzi🇮🇹 · V. Carassiti🇮🇹 · M. Chiosso🇮🇹 · R. Cimino🇮🇹 · G. Ciullo🇮🇹 · M. Contalbrigo🇮🇹 · U. D'Alesio🇮🇹 · P. Di Nezza🇮🇹 · R. Engels🇩🇪 and 19 other authors

    LHCSpin aims at installing a polarized gas target in front of the LHCb spectrometer, bringing, for the first time, polarized physics to the LHC. The project will benefit from the experience achieved with the installation of an unpolarized gas target at LHCb during the LHC Long Shutdown 2. LHCb will then become the first experiment simultaneously running in collider and fixed-target mode with polarized targets, opening a whole new range of explorations to its exceptional spectrometer. LHCSpin will offer a unique opportunity to probe polarized quark and gluon parton distributions in nucleons and nuclei, especially at high $x$ and intermediate $Q^2$, where experimental data are still largely missing. Beside standard collinear parton distribution functions (PDFs), LHCSpin will make it possible to study multidimensional polarized parton distributions that depend also on parton transverse momentum. The study of the multidimensional partonic structure of the nucleon, particularly including polarization effects, can test our knowledge of QCD at an unprecedented level of sophistication, both in the perturbative and nonperturbative regime. At the same time, an accurate knowledge of hadron structure is necessary for precision measurements of Standard Model (SM) observables and discovery of physics beyond the SM. Due to the intricate nature of the strong interaction, it is indispensable to perform the widest possible suite of experimental measurements. It will be ideal to have two new projects complementing each other: a new facility for polarized electron-proton collisions and a new facility for polarized proton-proton collisions. LHCSpin stands out at the moment as the most promising candidate for the second type of project, going beyond the kinematic coverage and the accuracy of the existent experiments, especially on the heavy-quark sector.

    ↳ hep-exhep-ph69 citations
19. 19*

    On the photon mass in Very Special Relativity

    Jorge Alfaro🇨🇱 · Alex Soto🇨🇱

    In Very Special Relativity (VSR) a gauge invariant photon mass is allowed. We explore some consequences of keeping this parameter not zero. VSR-Maxwell equations are presented. In addition, we show modifications to the Feynman rules keeping the photon mass and we apply it in the computation of the electron self energy, whose result is free from infrared divergences. A computation of the Coulomb scattering is developed and a small signal of the privileged direction predicted in the theory is present at tree level. Radiative corrections are computed and the photon mass cancels due to soft photon emission as in the standard case.

    ↳ hep-thhep-phPRD(2019)·33 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.