PaperPanorama

HEP Phenomenology·hep-ph

Tue·Oct 27, 2020

47 papers35 primary·12 cross-listed·reconstructed*

  1. 01*

    Proton and neutron form factors with quark orbital excitations

    Yu. A. Simonov🇷🇺

    Nucleon form factors play an especially important role in studying the dynamics of nucleons and explicit structure of the wave functions at arbitrary nucleon velocity. The purpose of the paper is to explain theoretically all four nucleon form factors measured experimentally in the cross section measurements (by the Rosenbluth method), yielding almost equal normalized form factors , as well as in the polarization transfer experiments, where a strongly decreasing proton electric form factor has been discovered. It is shown, using relativistic hyperspherical formalism, that the nucleon wave functions in the lowest approximation provide almost equal normalized form factors as seen in the Rosenbluth cross sections, but in the higher components they contain a large admixture of the quark orbital momenta, which strongly decreases and this effect is possibly detected in the polarization transfer method (not seen in the classical cross section experiments). Moreover, the same admixture of the higher components explains the small positive form factor . The resulting form factors, are calculated up to GeV, using the standard and the Lorentz contracted wave functions and shown to be in reasonable agreement with experimental data.

    hep-phhep-exEPJA(2021)·7 citations
  2. 02*

    Gluon dynamics from an ordinary differential equation

    A. C. Aguilar🇧🇷 · M. N. Ferreira🇧🇷 · J. Papavassiliou🇪🇸

    We present a novel method for computing the nonperturbative kinetic term of the gluon propagator from an exactly solvable ordinary differential equation, whose origin is the fundamental Slavnov-Taylor identity satisfied by the three-gluon vertex, evaluated in a special kinematic limit. The main ingredients comprising the solution are a well-known projection of the three-gluon vertex, simulated on the lattice, and a particular derivative of the ghost-gluon kernel, whose approximate form is derived from a standard Schwinger-Dyson equation. Crucially, the physical requirement of a pole-free answer determines completely the form of the initial condition, whose value is calculated from a specific integral containing the same ingredients as the solution itself. This outstanding feature fixes uniquely, at least in principle, the form of the kinetic term, once the ingredients of the differential equation have been accurately evaluated. Furthermore, in the case where the gluon propagator has been independently accessed from the lattice, this property leads to the unambiguous extraction of the momentum-dependent effective gluon mass. The practical implementation of this method is carried out in detail, and the required approximations and theoretical assumptions are duly highlighted. The systematic improvement of this approach through the detailed computation of one of its pivotal components is briefly outlined.

    hep-phhep-lathep-thEPJC(2021)·14 citations
  3. 03*

    Sensitivities of future reactor and long-baseline neutrino experiments to NSI

    Pouya Bakhti🇮🇷 · Meshkat Rajaee🇮🇷

    We investigate the potential of the next generation long-baseline neutrino experiments DUNE and T2HK as well as the upcoming reactor experiment JUNO to constrain Non-Standard Interaction (NSI) parameters. JUNO is going to provide the most precise measurements of solar neutrino oscillation parameters as well as determining the neutrino mass ordering. We study how the results of JUNO combined with those of long-baseline neutrino experiments such as DUNE and T2HK can help to determine oscillation parameters and to constrain NSI parameters. We present excluded regions in NSI parameter space, assuming Standard Model (SM) as the null hypothesis. We further explore the correlations between the NSI parameters and CP-violation phase.

    hep-phhep-exPRD(2021)·17 citations
  4. 04*

    Contributions of the kaon pair from for the three-body decays

    Ai-Jun Ma🇨🇳 · Wen-Fei Wang🇨🇳

    We study the contributions of the kaon pair originating from the resonance for the three-body decays by employing the perturbative QCD approach. According to the predictions in this work, the contributions from the intermediate state are relatively small for the three-body decays such as , , and , while about of the total three-body branching fraction for could possibly come from the subprocess . We also estimate the branching fractions for decay into the kaon pair to be about , and that for the neutral decay into or to be about , which will be tested by future experiments.

    hep-phPRD(2021)·15 citations
  5. 05*

    Mathematical properties of nested residues and their application to multi-loop scattering amplitudes

    J. Jesus Aguilera-Verdugo🇪🇸 · Roger J. Hernandez-Pinto🇲🇽 · German Rodrigo🇪🇸 · German F. R. Sborlini🇩🇪 · William J. Torres Bobadilla🇩🇪

    The computation of multi-loop multi-leg scattering amplitudes plays a key role to improve the precision of theoretical predictions for particle physics at high-energy colliders. In this work, we focus on the mathematical properties of the novel integrand-level representation of Feynman integrals, which is based on the Loop-Tree Duality (LTD). We explore the behaviour of the multi-loop iterated residues and explicitly show, by developing a general formal proof for the first time, that contributions associated to displaced poles are cancelled out. The remaining residues, called nested residues as originally introduced in Ref. \cite{Verdugo:2020kzh}, encode the relevant physical information and are naturally mapped onto physical configurations associated to nondisjoint on-shell states. By going further on the mathematical structure of the nested residues, we prove that unphysical singularities vanish, and show how the final expressions can be written by using only causal denominators. In this way, we provide a mathematical proof for the all-loop formulae presented in Ref. \cite{Aguilera-Verdugo:2020kzc}.

    hep-phhep-thmath-phmath.MPJHEP(2021)·60 citations
  6. 06*

    Chiral symmetry breaking and chemical equilibrium in a heavy-ion collisions

    Sourendu Gupta🇮🇳 · Jajati K. Nayak🇮🇳 · Sushant K. Singh🇮🇳

    We examine the thermalization of an ensemble of the octet of pseudoscalar mesons, in the isospin symmetric limit, whose interactions are constrained through chiral symmetry, unitarity, and measurements. The reaction amplitudes generate all resonances up to masses of about 2 GeV, with twelve input parameters, namely f_pi, three masses, and eight low energy constants (LECs) of chiral perturbation theory. In linear response theory, we find that matter takes an extremely long time to thermalize. These long relaxation times are directly related to the fact that these mesons are pseudo-Goldstone bosons of chiral symmetry breaking. This result indicates that fireballs created with zero baryon number in heavy-ion collisions will drop out of chemical equilibrium once they enter the chiral symmetry broken phase.

    hep-phhep-exnucl-thPRD(2021)·4 citations
  7. 07*

    Sudakov effects in central-forward dijet production in high energy factorization

    A. van Hameren🇵🇱 · P. Kotko🇵🇱 · K. Kutak🇵🇱 · S. Sapeta🇵🇱

    We discuss central-forward dijet production at LHC energies within the framework of high energy factorization. In our study, we profit from the recent progress on consistent merging of Sudakov resummation with small- effects, which allows us to compute two different gluon distributions which depend on longitudinal momentum, transverse momentum and the hard scale of the process: one for the quark channel and one for the gluon channel. The small- resummation is included by means of the BK equation supplemented with a kinematic constraint and subleading corrections. We test the new gluon distributions against existing CMS data for transverse momentum spectra in forward-central dijet production. We obtain results which are largely consistent with our earlier predictions based on model implementation of Sudakov form factors. In addition, we study dijet azimuthal decorrelations for the forward-central jets, which are known to be sensitive to the modeling of soft radiation.

    hep-phPLB(2021)·28 citations
  8. 08*

    Five-zero texture in neutrino-dark matter model within the framework of minimal extended seesaw

    Pritam Das🇮🇳 · Mrinal Kumar Das🇮🇳 · Najimuddin Khan🇮🇳

    We study a model of neutrino and dark matter within the framework of a minimal extended seesaw. This model is based on flavour symmetry along with the discrete symmetry to stabilize the dark matter and construct desired mass matrices for neutrino mass. Five-zero textures are imposed in the final active-sterile mass matrix, which significantly reduces free parameter in the model. Three right-handed neutrinos were considered, two of them have nearly degenerate masses which help us to achieve baryogenesis via resonant leptogenesis. A singlet fermion (sterile neutrino) with mass (eV) is also considered, and we are able to put bounds on active-sterile mixing parameters via neutrino oscillation data. Resonant enhancement of lepton asymmetry is studied at TeV scale, where we discuss a few aspects of baryogenesis considering the flavour effects. Possibility of improvement in effective mass from in the presence of a single generation of sterile neutrino flavour is also studied within the fermion sector. In the scalar sector, the imaginary component of the complex singlet scalar is behaving as a potential dark matter candidate and simultaneously the real part of the complex scalar is associated with the fermion sector for sterile mass generation. A broad region of dark matter mass is analyzed from various annihilation processes, and the VEV of the complex scalar plays a pivotal role to achieve the observed relic density at the right ballpark.

    hep-phNPB(2022)·6 citations
  9. 09*

    Mono-top signature from stop decay at the HE-LHC

    Xu-Xu Yang🇨🇳 · Hang Zhou🇨🇳 · Tian-Peng Tang🇨🇳 · Ning Liu🇨🇳

    Searching for the top squark (stop) is a key task to test the naturalness of SUSY. Different from stop pair production, single stop production relies on its electroweak properties and can provide some unique signatures. Following the single production process , the top quark has two decay channels: leptonic channel and hadronic channel. In this paper, we probe the observability of these two channels in a simplified MSSM scenario. We find that, at the 27 TeV LHC with the integrated luminosity of , GeV and GeV can be excluded at through the leptonic mono-top channel, while GeV and GeV can be excluded at through the hadronic channel.

    hep-phCommun.Theor.Phys.(2021)·0 citations
  10. 10*

    The three jewels in the crown of the LHC

    Yosef Nir🇮🇱

    The ATLAS and CMS experiments have made three major discoveries: The discovery of an elementary spin-zero particle, the discovery of the mechanism that makes the weak interactions short-range, and the discovery of the mechanism that gives the third generation fermions their masses. I explain how this progress in our understanding of the basic laws of Nature was achieved.

    hep-phCERN Cour.(2020)·10 citations
  11. 11*

    In-medium mass shift by the meson loop effect

    Rahul Chhabra🇮🇳 · Kazuo Tsushima🇧🇷

    By an effective Lagrangian plus QCD sum-rule approach, we investigate the mass shift of the state in medium, in symmetric nuclear matter with zero and finite temperature, and cold strange matter. The in-medium mass of the state is evaluated through the intermediate pseudoscalar -meson loop for the self-energy. The effect of medium is incorporated through the in-medium mass of meson calculated using chiral SU(3) model plus QCD sum-rule approach. The self energy loop integral is regularized using the phenomenological form factor of the dipole form. We compare our results with some of the results in the literature. The present results should be helpful to understand better the expected data from heavy ion collision experiments, such as CBM and PANDA.

    hep-phJ.Phys.Conf.Ser.(2020)·2 citations
  12. 12*

    Vector mesons spectrum in a medium with a chiral imbalance induced by the vacuum of fermions

    Vladimir Kovalenko🇷🇺 · Alexander Andrianov🇷🇺 · Vladimir Andrianov🇷🇺

    The properties of the light vector mesons in the presence of local parity breaking medium with a chiral imbalance are considered in the vector-meson dominance model. Applying the finite lowest-order radiatively induced local effective Lagrangian, initially developed for the QED, for the vector and mesons, we obtained the mass spectrum as a function of momentum and chiral chemical potential . We showed that in addition to the Chern-Simons term, splitting the transverse polarisations of the mesons, there is another radiatively induced contribution that becomes important at momentum and around a few hundred MeV.

    hep-phnucl-thJ.Phys.Conf.Ser.(2020)·4 citations
  13. 13*

    Improved Treatment of Dark Matter Capture in Neutron Stars II: Leptonic Targets

    Nicole F. Bell🇦🇺 · Giorgio Busoni🇩🇪 · Sandra Robles🇦🇺 · Michael Virgato🇦🇺

    Neutron stars harbour matter under extreme conditions, providing a unique testing ground for fundamental interactions. We recently developed an improved treatment of dark matter (DM) capture in neutron stars that properly incorporates many of the important physical effects, and outlined useful analytic approximations that are valid when the scattering amplitude is independent of the centre of mass energy. We now extend that analysis to all interaction types. We also discuss the effect of going beyond the zero-temperature approximation, which provides a boost to the capture rate of low mass dark matter, and give approximations for the dark matter up-scattering rate and evaporation mass. We apply these results to scattering of dark matter from leptonic targets, for which a correct relativistic description is essential. We find that the potential neutron star sensitivity to DM-lepton scattering cross sections greatly exceeds electron-recoil experiments, particularly in the sub-GeV regime, with a sensitivity to sub-MeV DM well beyond the reach of future terrestrial experiments.

    hep-phastro-ph.COastro-ph.HEJCAP(2021)·93 citations
  14. 14*

    Detecting anomaly in vector boson scattering

    Jinmian Li🇨🇳 · Shuo Yang🇨🇳 · Rao Zhang🇨🇳

    Measuring the vector boson scattering (VBS) precisely is an important step towards understanding the electroweak symmetry breaking of the standard model (SM) and detecting new physics beyond the SM. We propose a neural network which compress the features of the VBS into three dimensional latent space. The consistency of the SM prediction and the experimental data is tested by the binned log-likelihood analysis in the latent space. We will show that the network is capable of distinguish different polarization modes of production in both dileptonic channel and semi-leptonic channel. The method is also applied to constrain the effective field theory and two Higgs Doublet Model. The results demonstrate that the method is sensitive to generic new physics contributing to the VBS.

    hep-phhep-exCPC(2021)·3 citations
  15. 15*

    The study of two quasi-degenerate heavy sterile neutrinos in rare meson decays

    Jiabao Zhang🇨🇳 · Tianhong Wang🇨🇳 · Geng Li🇨🇳 · Yue Jiang🇨🇳 · Guo-Li Wang🇨🇳

    In this work, we study the lepton-number-violating processes of and mesons. Two quasi-degenerate sterile neutrinos are assumed to induce such processes. Different with the case where only one sterile neutrino involves, here, the CP phases of the mixing parameters could give sizable contribution. This, in turn, would affect the absolute values of the mixing parameters determined by the experimental upper limits of the branching fractions. A general function which express the difference of the mixing parameters for two-generation and one-generation is presented. Special cases with specific relations of the parameters are discussed. Besides, we also thoroughly investigate the CP violation effect of such processes. It is shown that generally is a function of the sterile neutrino mass.

    hep-phPRD(2021)·12 citations
  16. 16*

    The future probe of the light Higgs boson pair production

    Ning Chen🇨🇳 · Tong Li🇨🇳 · Wei Su🇦🇺 · Yongcheng Wu🇨🇦

    In this work we study the light Higgs scenario in the framework of two Higgs doublet model (2HDM). In this case the heavier CP-even Higgs boson in 2HDM is the SM-like Higgs with 125 GeV mass and a CP-even Higgs boson lighter than 125 GeV exhibits in the spectrum. We find that this scenario exists in the alignment limit of and is still allowed by the global fit of the 125 GeV Higgs and the direct searches for and . The case of is highly constrained as the exotic decay mode is kinematically allowed. We focus on the case and simulate the pair production of the light Higgs boson at the LHC. The pair production is sensitive to the soft symmetry breaking term in the 2HDM potential through the Higgs self-couplings. We find that the future high-luminosity LHC can discover the signal in the region of and GeV allowed by the theoretical constraints.

    hep-phhep-ex3 citations
  17. 17*

    Wigner functions and quantum kinetic theory of polarized photons

    Koichi Hattori🇯🇵 · Yoshimasa Hidaka🇯🇵 · Naoki Yamamoto🇯🇵 · Di-Lun Yang🇯🇵

    We derive the Wigner functions of polarized photons in the Coulomb gauge with the expansion applied to quantum field theory, and identify side-jump effects for massless photons. We also discuss the photonic chiral vortical effect for the Chern-Simons current and zilch vortical effect for the zilch current in local thermal equilibrium as a consistency check for our formalism. The results are found to be in agreement with those obtained from different approaches. Moreover, using the real-time formalism, we construct the quantum kinetic theory (QKT) for polarized photons. By further adopting a specific power counting scheme for the distribution functions, we provide a more succinct form of an effective QKT. This photonic QKT involves quantum corrections associated with self-energy gradients in the collision term, which are analogous to the side-jump corrections pertinent to spin-orbit interactions in the chiral kinetic theory for massless fermions. The same theoretical framework can also be directly applied to weakly coupled gluons in the absence of background color fields.

    hep-phastro-ph.HEcond-mat.otherhep-th+1JHEP(2021)·53 citations
  18. 18*

    A Real Triplet-Singlet Extended Standard Model: Dark Matter and Collider Phenomenology

    Nicole F. Bell🇦🇺 · Matthew J. Dolan🇦🇺 · Leon S. Friedrich🇦🇺 · Michael J. Ramsey-Musolf🇨🇳 · Raymond R. Volkas🇦🇺

    We examine the collider and dark matter phenomenology of the Standard Model extended by a hypercharge-zero SU(2) triplet scalar and gauge singlet scalar. In particular, we study the scenario where the singlet and triplet are both charged under a single symmetry. We find that such an extension is capable of generating the observed dark matter density, while also modifying the collider phenomenology such that the lower bound on the mass of the triplet is smaller than in minimal triplet scalar extensions to the Standard Model. A high triplet mass is in tension with the parameter space that leads to novel electroweak phase transitions in the early universe. Therefore, the lower triplet masses that are permitted in this extended model are of particular importance for the prospects of successful electroweak baryogenesis and the generation of gravitational waves from early universe phase transitions.

    hep-phJHEP(2020)·16 citations
  19. 19*

    Towards constraining triple gluon operators through tops

    Debjyoti Bardhan🇮🇱 · Diptimoy Ghosh🇮🇳 · Prasham Jain🇮🇳 · Arun M. Thalapillil🇮🇳

    Effective field theory techniques provide us important tools to probe for physics beyond the Standard Model in a relatively model-independent way. In this work, we revisit the CP-even dimension-6 purely gluonic operator to investigate the possible constraints on it by studying its effect on top-pair production at the LHC, in particular the high and tails of the distribution. Cut-based analysis reveals that the scale of New Physics when this operator alone contributes to the production process is greater than 3.4 TeV at 95% C.L., which is a much stronger bound compared to the bound of 850 GeV obtained from Run-I data using the same channel. This is reinforced by an analysis using Machine Learning techniques. Our study complements similar studies that have focussed on other collider channels to study this operator.

    hep-phhep-exPRD(2021)·5 citations
  20. 20*

    Potential linear and angular momentum in the scalar diquark model

    David Arturo Amor-Quiroz🇫🇷 · Matthias Burkardt🇺🇸 · William Focillon🇫🇷 · Cédric Lorcé🇫🇷

    We present an analytic two-loop calculation within the scalar diquark model of the potential linear and angular momenta, defined as the difference between the Jaffe-Manohar and Ji notions of linear and angular momenta. As expected by parity and time-reversal symmetries, a direct calculation confirms that the potential transverse momentum coincides with the Jaffe-Manohar (or canonical) definition of average quark transverse momentum, also known as the quark Sivers shift. We examine whether initial/final-state interactions at the origin of the Sivers asymmetry can also generate a potential angular momentum in the scalar diquark model.

    hep-phEPJC(2021)·4 citations
  21. 21*

    Morphology for Jet Classification

    Sung Hak Lim🇺🇸 · Mihoko M. Nojiri🇯🇵

    We introduce a jet tagger based on a neural network analyzing the Minkowski Functionals (MFs) of pixellated jet images. The MFs are geometric measures of binary images, and they can be regarded as a generalization of the particle multiplicity, which is an important quantity in jet tagging. Their changes by dilation encode the jet constituents' geometric structures that appear at various angular scales. We explicitly show that this analysis using the MFs together with mathematical morphology can be considered a constrained convolutional neural network (CNN). Conversely, CNN could model the MFs in a certain limit, and we show their correlation in the example of tagging semi-visible jets emerging from the strong interaction of a hidden valley scenario. The MFs are independent of the IRC-safe observables commonly used in jet physics. We combine this morphological analysis with an IRC-safe relation network which models two-point energy correlations. While the resulting network uses constrained input parameters, it shows comparable dark jet and top jet tagging performances to the CNN. The architecture has significant computational advantages when the available data is limited. We show that its tagging performance is much better than that of the CNN with a small number of training samples. We also qualitatively discuss their parton-shower model dependency. The results suggest that the MFs can be an efficient parameterization of the IRC-unsafe feature space of jets.

    hep-phhep-exPRD(2022)·17 citations
  22. 22*

    Kinetic and Chemical Equilibration of Quark-Gluon Plasma

    Xiaojian Du🇩🇪 · Sören Schlichting🇩🇪

    We solve a leading-order QCD kinetic theory with light quarks and gluon degrees of freedom to study the non-equilibrium dynamics of the quark-gluon plasma (QGP). By including both elastic and inelastic scatterings for quarks and gluon, the model is proficient to describe kinetic and chemical equilibration of the QGP, and thus connects the initial (semi-) hard production of partons at early times with the hydrodynamic description of a near-thermalized quark-gluon plasma after the first fm/c of the collision. Within this approach, we investigate the time scales and mechanisms for kinetic and chemical equilibration of the QGP at zero and non-zero net-baryon density and elaborate on the connections to jet quenching physics and hydrodynamics.

    hep-phnucl-thPoS(2021)·1 citation
  23. 23*

    Di-lepton production from a single photon in strong magnetic fields: Vacuum dichroism

    Koichi Hattori🇯🇵 · Hidetoshi Taya🇯🇵 · Shinsuke Yoshida🇨🇳

    We study di-lepton production from a single photon in the presence of a strong constant magnetic field. By the use of the Ritus-basis formalism, we analytically evaluate the photon--to--di-lepton conversion vertex with fully taking into account the non-perturbative interactions between the produced fermions and the strong magnetic field. We show that the di-lepton spectrum becomes anisotropic with respect to the magnetic-field direction and depends on the photon polarization as a manifestation of the vacuum dichroism in a strong magnetic field. According to the energy conservation in the presence of the Landau quantization, not only the transverse momentum of the produced fermions but also the longitudinal momentum is discretized, and the di-lepton spectrum exhibits spike structures as functions of the incident photon energy and the magnetic field strength. We also show that the di-lepton production is strictly prohibited for massless fermions in the lowest Landau levels as an analogue of the so-called helicity suppression.

    hep-phastro-ph.HEnucl-thJHEP(2021)·41 citations
  24. 24*

    Viscous damping of chiral dynamos in the early universe

    A.Neronov🇫🇷 · D.Semikoz🇫🇷

    Chiral dynamo converting asymmetry between right and left-handed leptons in the early universe into helical magnetic field has been proposed as a possible cosmological magnetogenesis scenario. We show that this mechanism is strongly affected by viscous damping of primordial plasma motions excited by the dynamo. This effect modifies the expected range of strength and correlation length of the chiral dynamo field which could have survived till present epoch in the voids of the Large Scale Structure. We show the range of parameters of chiral dynamo field that may have survived in the voids is still consistent with existing lower bounds on intergalactic magnetic field from gamma-ray observations, but only if the right-left lepton asymmetry at the temperature T~80 TeV is very high, close to the maximal possible value.

    hep-phastro-ph.COastro-ph.HEhep-th5 citations
  25. 25*

    Condensates and pressure of two-flavor chiral perturbation theory at nonzero isospin and temperature

    Prabal Adhikari🇺🇸 · Jens O. Andersen🇳🇴 · Martin A. Mojahed🇳🇴

    We consider two-flavor chiral perturbation theory (PT) at finite isospin chemical potential and finite temperature . We calculate the effective potential and the quark and pion condensates as functions of and to next-to-leading order in the low-energy expansion in the presence of a pionic source. We map out the phase diagram in the -- plane. Numerically, we find that the transition to the pion-condensed phase is second order in the region of validity of PT, which is in agreement with model calculations and lattice simulations. Finally, we calculate the pressure to two-loop order in the symmetric phase for nonzero and find that PT seems to be converging very well.

    hep-phnucl-thEPJC(2021)·25 citations
  26. 26*

    New physics of strong interaction and Dark Universe

    V. Beylin🇷🇺 · M. Khlopov🇷🇺 · V. Kuksa🇷🇺 · N. Volchanskiy🇷🇺

    The history of dark universe physics can be traced from processes in the very early universe to the modern dominance of dark matter and energy. Here, we review the possible nontrivial role of strong interactions in cosmological effects of new physics. In the case of ordinary QCD interaction, the existence of new stable colored particles such as new stable quarks leads to new exotic forms of matter, some of which can be candidates for dark matter. New QCD-like strong interactions lead to new stable composite candidates bound by QCD-like confinement. We put special emphasis on the effects of interaction between new stable hadrons and ordinary matter, formation of anomalous forms of cosmic rays and exotic forms of matter, like stable fractionally charged particles. The possible correlation of these effects with high energy neutrino and cosmic ray signatures opens the way to study new physics of strong interactions by its indirect multi-messenger astrophysical probes.

    hep-phUniverse(2020)·49 citations
  27. 27*

    QGP modification to single inclusive jets in a calibrated transport model

    Weiyao Ke🇺🇸 · Xin-Nian Wang🇨🇳

    We study inclusive jet suppression and modifications in the quark-gluon plasma (QGP) with a transport-based model. The model includes vacuum-like parton shower evolution at high-virtuality, a linearized transport for jet-medium interactions, and a simple ansatz for the jet-induced hydrodynamic response of the medium. Model parameters are calibrated to nuclear modification factors for inclusive hadron and single inclusive jets with cone size in 0-10% central Au-Au and Pb-Pb collisions measured at the RHIC and LHC. The calibrated model consistently describes the cone-size dependent , modifications to inclusive jet fragmentation functions and jet shape. We discuss the origin of these modifications by analyzing the medium-induced jet energy flow in this model and elucidate the interplay of hard parton evolution and jet-induced medium response. In particular, we demonstrate that the excess of soft hadrons at GeV/ in jet fragmentation function and jet shape at large are consequences of both soft medium-induced gluon radiation and jet-induced medium excitation.

    hep-phnucl-thJHEP(2021)·73 citations
  28. 28*

    Variations on the SU(5) axion

    Jérémie Quevillon🇫🇷 · Christopher Smith🇫🇷

    The simultaneous embeddings of an axion state and a seesaw mechanism within the SU(5) Grand Unification Theory, both minimal and flipped, are systematically studied. It is shown that whenever B-L is active as a global symmetry, the PQ charges of the fermions are ambiguous. Various realizations of the seesaw mechanism are then found to differ only in the way this ambiguity is resolved. But since the ambiguity is unphysical, all these models are thereby predicted to be equivalent, in the sense that the axion phenomenology is identical at the low energy scale.

    hep-phhep-thEur.Phys.J.Plus(2022)·9 citations
  29. 29*

    Spontaneous chiral symmetry breaking in the massive Landau gauge: realistic running coupling

    Marcela Peláez🇺🇾 · Urko Reinosa🇫🇷 · Julien Serreau🇫🇷 · Matthieu Tissier🇫🇷 · Nicolás Wschebor🇺🇾

    We investigate the spontaneous breaking of chiral symmetry in QCD by means of a recently proposed approximation scheme in the Landau-gauge Curci-Ferrari model, which combines an expansion in the Yang-Mills coupling and in the inverse number of colors, without expanding in the quark-gluon coupling. The expansion allows for a consistent treatment of ultraviolet tails via renormalization group techniques. At leading order, it leads to the resummation of rainbow diagrams for the quark propagator, with, however, a trivial running of both the gluon mass and the quark-gluon coupling. In a previous work, by using a simple model for a more realistic running of these parameters, we could reproduce the known phenomenology of chiral symmetry breaking, including a satisfactory description of the lattice data for the quark mass function. Here, we get rid of this model-dependence by taking our approximation scheme to next-to-leading order. This allows us to consistently include the realistic running of the parameters and to access the unquenched gluon and ghost propagators to first nontrivial order, which we can compare to available lattice data for an even more stringent test of our approach. In particular, our results for the various two-point functions compare well with lattice data while the parameters of the model are strongly constrained.

    hep-phhep-lathep-thPRD(2021)·25 citations
  30. 30*

    Symmetries of the 2HDM: an invariant formulation and consequences

    P. M. Ferreira🇵🇹 · B. Grzadkowski🇵🇱 · O. M. Ogreid🇳🇴 · P. Osland🇳🇴

    Symmetries of the Two-Higgs-Doublet Model (2HDM) potential that can be extended to the whole Lagrangian, i.e. the CP-symmetries CP1, CP2, CP3 and the Higgs-family symmetries Z2, U(1) and SO(3) are discussed. Sufficient and necessary conditions in terms of constraints on masses and physical couplings for the potential to respect each of these symmetries are found. Each symmetry can be realized through several alternative cases, each case being a set of relations among physical parameters. We will show that some of those relations are invariant under the renormalization group, but others are not. The cases corresponding to each symmetry group are illustrated by analyzing the interplay between the potential and the vacuum expectation values.

    hep-phJHEP(2021)·19 citations
  31. 31*

    Chiral phase structure and critical end point in QCD

    Fei Gao🇩🇪 · Jan M. Pawlowski🇩🇪

    We map out the QCD phase structure at finite temperature and chemical potential for 2-flavour and 2 + 1-flavour QCD. This is done within a generalised functional approach to QCD put forward in arXiv:2002.07500 [hep-ph]. Specifically we compute the quark propagator and the finite-temperature and density fluctuations of the gluon propagator and the quark-gluon vertex on the basis of precision data for vacuum correlation functions. The novel ingredient is the direct self-consistent computation of the DSEs for the dressings of the quark-gluon vertex, in contrast to the common use of STI-inspired vertices. For small densities the results for the chiral order parameter agree with the respective lattice and functional renormalisation group results, for large densities the present results are in a quantitative agreement with the latter, including the location of the critical end point.

    hep-phhep-thPLB(2021)·202 citations
  32. 32*

    Systematizing and addressing theory uncertainties of unitarization with the Inverse Amplitude Method

    Alexandre Salas-Bernárdez🇪🇸 · Felipe J. Llanes-Estrada🇪🇸 · Juan Escudero-Pedrosa (Univ. Complutense Madrid)🇪🇸 · Jose Antonio Oller (Univ. Murcia)🇪🇸

    Effective Field Theories (EFTs) constructed as derivative expansions in powers of momentum, in the spirit of Chiral Perturbation Theory (ChPT), are a controllable approximation to strong dynamics as long as the energy of the interacting particles remains small, as they do not respect exact elastic unitarity. This limits their predictive power towards new physics at a higher scale if small separations from the Standard Model are found at the LHC or elsewhere. Unitarized chiral perturbation theory techniques have been devised to extend the reach of the EFT to regimes where partial waves are saturating unitarity, but their uncertainties have hitherto not been addressed thoroughly. Here we take one of the best known of them, the Inverse Amplitude Method (IAM), and carefully following its derivation, we quantify the uncertainty introduced at each step. We compare its hadron ChPT and its electroweak sector Higgs EFT applications. We find that the relative theoretical uncertainty of the IAM at the mass of the first resonance encountered in a partial-wave is of the same order in the counting as the starting uncertainty of the EFT at near-threshold energies, so that its unitarized extension should \textit{a priori} be expected to be reasonably successful. This is so provided a check for zeroes of the partial wave amplitude is carried out and, if they appear near the resonance region, we show how to modify adequately the IAM to take them into account.

    hep-phnucl-thSciPost Phys.(2021)·29 citations
  33. 33*

    Hunting for CP-violating axionlike particle interactions

    Luca Di Luzio🇩🇪 · Ramona Gröber🇮🇹 · Paride Paradisi🇮🇹

    The impact of axion-like particles (ALPs) on the search of permanent electric dipole moments (EDMs) of molecules, atoms, nuclei and nucleons is systematically investigated. We classify first the full set of CP-violating Jarlskog invariants emerging in the ALP effective field theory (EFT) containing operators up to dimension-5. Then, we evaluate the leading short-distance effects to the EDMs up to two-loop order. The high sensitivity of EDMs to CP-violating ALP interactions is emphasised exploiting both the current and projected experimental sensitivities.

    hep-phhep-exPRD(2021)·64 citations
  34. 34*

    Comprehensive analysis of beta decays within and beyond the Standard Model

    Adam Falkowski🇫🇷 · Martín González-Alonso🇪🇸 · Oscar Naviliat-Cuncic🇫🇷

    Precision measurements in allowed nuclear beta decays and neutron decay are reviewed and analyzed both within the Standard Model and looking for new physics. The analysis incorporates the most recent experimental and theoretical developments. The results are interpreted in terms of Wilson coefficients describing the effective interactions between leptons and nucleons (or quarks) that are responsible for beta decay. New global fits are performed incorporating a comprehensive list of precision measurements in neutron decay, superallowed transitions, and other nuclear decays that include, for the first time, data from mirror beta transitions. The results confirm the - character of the interaction and translate into updated values for and at the level. We also place new stringent limits on exotic couplings involving left-handed and right-handed neutrinos, which benefit significantly from the inclusion of mirror decays in the analysis.

    hep-phnucl-exnucl-thJHEP(2021)·123 citations
  35. 35*

    Anomalous Dimensions of Effective Theories from Partial Waves

    Pietro Baratella🇩🇪 · Clara Fernandez🇪🇸 · Benedict von Harling🇪🇸 · Alex Pomarol🇪🇸

    On-shell amplitude methods have proven to be extremely efficient for calculating anomalous dimensions. We further elaborate on these methods to show that, by the use of an angular momentum decomposition, the one-loop anomalous dimensions can be reduced to essentially a sum of products of partial waves. We apply this to the SM EFT, and show how certain classes of anomalous dimensions have their origin in the same partial-wave coefficients. We also use our result to obtain a generic formula for the one-loop anomalous dimensions of nonlinear sigma models at any order in the energy expansion, and apply our method to gravity, where it proves to be very advantageous even in the presence of IR divergencies.

    hep-phhep-thJHEP(2021)·45 citations
  36. 36*

    Constraining Mirror Dark Matter Inside Neutron Stars

    Raul Ciancarella🇮🇹 · Francesco Pannarale🇮🇹 · Andrea Addazi🇨🇳 · Antonino Marciano🇨🇳

    We inspect the possibility that neutron star interiors are a mixture of ordinary matter and mirror dark matter. This is a scenario that can be naturally envisaged according to well studied accretion mechanisms, including the Bondi-Hoyle one. We show that the inclusion of mirror dark matter in neutron star models lowers the maximum neutron star mass for a given equation of state, and that it decreases the tidal deformability of a given neutron star. These general features imply that, given an equation of state, one can constrain the maximum viable amount of mirror dark matter in neutron stars in order to consistently fulfill existing maximum mass and tidal deformability constraints. Conversely, using tidal deformability measurements to rule out equations of state requires making assumptions on the amount of mirror dark matter contained in neutron stars. Finally, the presence of mirror dark matter also modifies the universal relation that links the tidal deformability of a neutron star to its compactness. Therefore, caution is mandatory when considering exotic models, such as the ones discussed in this paper.

    astro-ph.HEgr-qchep-phPhys.Dark Univ.(2021)·31 citations
  37. 37*

    Searching for new physics with a levitated-sensor-based gravitational-wave detector

    Nancy Aggarwal🇺🇸 · George P. Winstone🇺🇸 · Mae Teo🇺🇸 · Masha Baryakhtar🇺🇸 · Shane L. Larson🇺🇸 · Vicky Kalogera🇺🇸 · Andrew A. Geraci🇺🇸

    The Levitated Sensor Detector (LSD) is a compact resonant gravitational-wave (GW) detector based on optically trapped dielectric particles that is under construction. The LSD sensitivity has more favorable frequency scaling at high frequencies compared to laser interferometer detectors such as LIGO. We propose a method to substantially improve the sensitivity by optically levitating a multi-layered stack of dielectric discs. These stacks allow the use of a more massive levitated object while exhibiting minimal photon recoil heating due to light scattering. Over an order of magnitude of unexplored frequency space for GWs above 10 kHz is accessible with an instrument 10 to 100 meters in size. Particularly motivated sources in this frequency range are gravitationally bound states of QCD axions with decay constant near the grand unified theory (GUT) scale that form through black hole superradiance and annihilate to GWs. The LSD is also sensitive to GWs from binary coalescence of sub-solar-mass primordial black holes and as-yet unexplored new physics in the high-frequency GW window.

    gr-qchep-phquant-phPRL(2022)·142 citations
  38. 38*

    Loop-Level Double-Copy for Massive Quantum Particles

    John Joseph M. Carrasco🇺🇸 · Ingrid A. Vazquez-Holm🇫🇷

    We find that scattering amplitudes in massive scalar QCD can manifest the duality between color and kinematics at loop-level. Specifically we construct the one-loop integrands for four-point scattering between two distinct massive scalars, and the five-point process encoding the first correction to massive scalar scattering with gluonic radiation. We find that factorization and the color-kinematics duality are sufficient principles to entirely bootstrap these calculations, allowing us to construct all contributions ultimately from the three-point tree-level amplitudes which are themselves entirely constrained by symmetry. Double-copy construction immediately provides the associated predictions for massive scalars scattering in the so called N=0 supergravity theory.

    hep-thgr-qchep-phPRD(2021)·65 citations
  39. 39*

    Distribution of Energy-Momentum Tensor around a Static Quark in the Deconfined Phase of SU(3) Yang-Mills Theory

    Ryosuke Yanagihara🇯🇵 · Masakiyo Kitazawa🇯🇵 · Masayuki Asakawa🇯🇵 · Tetsuo Hatsuda🇯🇵

    Energy momentum tensor (EMT) characterizes the response of the vacuum as well as the thermal medium under the color electromagnetic fields. We define the EMT by means of the gradient flow formalism and study its spatial distribution around a static quark in the deconfined phase of SU(3) Yang-Mills theory on the lattice. Although no significant difference can be seen between the EMT distributions in the radial and transverse directions except for the sign, the temporal component is substantially different from the spatial ones near the critical temperature . This is in contrast to the prediction of the leading-order thermal perturbation theory. The lattice data of the EMT distribution also indicate the thermal screening at long distance and the perturbative behavior at short distance.

    hep-lathep-phnucl-thPRD(2020)·14 citations
  40. 40*

    Probing Oscillons of Ultra-Light Axion-like Particle by 21cm Forest

    Masahiro Kawasaki🇯🇵 · Wakutaka Nakano🇯🇵 · Hiromasa Nakatsuka🇯🇵 · Eisuke Sonomoto🇯🇵

    Ultra-Light Axion-like Particle (ULAP) is motivated as one of the solutions to the small scale problems in astrophysics. When such a scalar particle oscillates with an amplitude in a potential shallower than quadratic, it can form a localized dense object, oscillon. Because of its longevity due to the approximate conservation of the adiabatic invariant, it can survive up to the recent universe as redshift . The scale affected by these oscillons is determined by the ULAP mass and detectable by observations of 21cm line. In this paper, we examine the possibility to detect ULAP by 21cm line and find that the oscillon can enhance the signals of 21cm line observations when and the fraction of ULAP to dark matter is much larger than depending on the form of the potential.

    astro-ph.COhep-phJCAP(2021)·17 citations
  41. 41*

    Curvature bounce in general relativity: background and primordial spectrum

    Cyril Renevey🇫🇷 · Aurélien Barrau🇫🇷 · Killian Martineau🇫🇷 · Selim Touati🇫🇷

    Recent data suggest that the Universe could be positively curved. Combined with an inflationary stage, this might lead to a curvature bounce instead of the Big Bang. The background evolution is presented, as a function of the parameters controlling the cosmic evolution. The primordial tensor spectrum is also calculated and possible observational footprints of the model are underlined. Several potentials are considered and general remarks are made about "naturalness" in this context.

    gr-qcastro-ph.COhep-phJCAP(2021)·12 citations
  42. 42*

    Gradient expansion formalism for magnetogenesis in the kinetic coupling model

    O.O. Sobol🇨🇭 · A.V. Lysenko🇺🇦 · E.V. Gorbar🇺🇦 · S.I. Vilchinskii🇨🇭

    In order to describe magnetogenesis during inflation in the kinetic coupling model, we utilize a gradient expansion which is based on the fact that only long-wavelength (superhorizon) modes undergo amplification. For this purpose, we introduce a set of functions (bilinear combinations of electromagnetic fields with an arbitrary number of spatial curls) satisfying an infinite chain of equations. Apart from the usual mode enhancement due to interaction with the inflaton, these equations also take into account the fact that the number of relevant modes constantly grows during inflation. Truncating this chain, we show that even with a relatively small number of equations, it is possible to describe the electric and magnetic energy densities with a few percent accuracy during the whole inflation stage. We arrive at this conclusion for different types of coupling functions (increasing, decreasing, and nonmonotonic) in the regime with strong backreaction and its absence.

    astro-ph.COgr-qchep-phPRD(2020)·19 citations
  43. 43*

    Energy budget and the gravitational wave spectra beyond the bag model

    Xiao Wang🇨🇳 · Fa Peng Huang🇺🇸 · Xinmin Zhang🇨🇳

    The energy budget of cosmological first-order phase transition is essential for the gravitational wave spectra. Most of the previous studies are based on the bag model with same sound velocity in the symmetric and broken phase. We study the energy budget and the corresponding gravitational wave spectra beyond the bag model, where the sound velocities could be different in the symmetric and broken phase. Taking the Higgs sextic effective model as a representative model, we calculate the sound velocities in different phase, the gravitational wave spectra and the signal-to-noise ratio for different combinations of phase transition parameters beyond the bag model. We compare these new results with the ones obtained from the bag model.The proper sound velocities and phase transition parameters at the appropriate temperature are important to obtain more precise predictions.

    astro-ph.COhep-phPRD(2021)·42 citations
  44. 44*

    Non-planar cusp and transcendental anomalous dimension at four loops in N=4 supersymmetric Yang-Mills theory

    B.A. Kniehl🇩🇪 · V.N. Velizhanin🇷🇺

    We compute the nonplanar contribution to the universal anomalous dimension of the SU(4)-singlet twist-two operators in N=4 supersymmetric Yang-Mills theory at four loops through Lorentz spin 18. From this, we numerically evaluate the nonplanar contribution to the four-loop lightlike cusp anomalous dimension and derive the transcendental and parts of the universal anomalous dimension for arbitrary Lorentz spin in analytic form. As for the lightlike cusp anomalous dimension and the part of the universal anomalous dimension, we confirm previous results.

    hep-thhep-phPRL(2021)·12 citations
  45. 45*

    Multi-particle Representations of the Poincaré Group

    Csaba Csáki🇺🇸 · Sungwoo Hong🇺🇸 · Yuri Shirman🇺🇸 · Ofri Telem🇺🇸 · John Terning🇺🇸

    In this work we extend the definition of asymptotic multi-particle states of the -matrix, beyond the direct products of one-particle states. We identify new quantum numbers which we call pairwise helicities, or , associated with asymptotically separated pairs of particles. These signal the appearance of a new source of angular momentum, beyond the orbital and spin contributions. The essence of our construction is to first treat all single particles as well as all particle pairs independently, ultimately projecting onto the physical states. The resulting representations reproduce the usual direct product states for vanishing , while for vanishing spins they reproduce Zwanziger's electric-magnetic multi-particle states. Pairwise helicity then appears as a label for the extra little group phase for our quantum states, in addition to their standard little group transformation. Our newly defined multi-particle states are the correct asymptotic states for the scattering of electric and magnetic charges, with pairwise helicity identified as .

    hep-thhep-phPRL(2021)·29 citations
  46. 46*

    Eclectic flavor scheme from ten-dimensional string theory -- II. Detailed technical analysis

    Hans Peter Nilles🇩🇪 · Saúl Ramos-Sánchez🇲🇽 · Patrick K.S. Vaudrevange🇩🇪

    String theory leads to a flavor scheme where modular symmetries play a crucial role. Together with the traditional flavor symmetries they combine to an eclectic flavor group, which we determine via outer automorphisms of the Narain space group. Unbroken flavor symmetries are subgroups of this eclectic group and their size depends on the location in moduli space. This mechanism of local flavor unification allows a different flavor structure for different sectors of the theory (such as quarks and leptons) and also explains the spontaneous breakdown of flavor- and CP-symmetries (via a motion in moduli space). We derive the modular groups, including CP and R-symmetries, for different sub-sectors of six-dimensional string compactifications and determine the general properties of the allowed flavor groups from this top-down perspective. It leads to a very predictive flavor scheme that should be confronted with the variety of existing bottom-up constructions of flavor symmetry in order to clarify which of them could have a consistent top-down completion.

    hep-thhep-phNPB(2021)·79 citations
  47. 47*

    Fully developed relativistic turbulence

    Esteban Calzetta🇦🇷

    We use a simple model consisting of energy-momentum tensor conservation and a Maxwell-Cattaneo equation for its viscous part to study nonlinear phenomena in a real relativistic fluid. We focus on new types of behavior without nonrelativistic equivalents, such as an entropy cascade driven by fluctuations in the tensor degrees of freedom of the theory. We write down the von Kármán-Howarth equations for this kind of turbulence, and consider the correlations corresponding to fully developed turbulence.

    gr-qchep-phPRD(2021)·17 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.