PaperPanorama

HEP Phenomenology·hep-ph

Mon·Nov 1, 2021

36 papers22 primary·14 cross-listed·reconstructed*

  1. 01*

    Phenomenological analysis of multi-pseudoscalar mediated dark matter models

    Shankha Banerjee🇨🇭 · Geneviève Bélanger🇫🇷 · Disha Bhatia🇮🇳 · Benjamin Fuks🇫🇷 · Sreerup Raychaudhuri🇮🇳

    Non-minimal simplified extensions of the Standard Model have gained considerable currency in the context of dark matter searches at the LHC, since they predict enhanced mono-Higgs and mono- signatures over large parts of the parameter space. However, these non-minimal models obviously lack the simplicity and directness of the original simplified models, and are more heavily dependent on the model assumptions. We propose to classify these models generically on the basis of additional mediator(s) and dark matter particles. As an example, we take up a scenario involving multiple pseudoscalar mediators, and a single Dirac dark matter particle, the latter being a popular introduction to ensure ultraviolet completion of theories with multiple pseudoscalar fields. In the chosen scenario, we discuss the viable channels and signatures of relevance at the future runs of the LHC. These are then compared with the minimal simplified scenarios and distinguishing features are pinpointed.

    hep-phhep-exJHEP(2022)·15 citations
  2. 02*

    Study of meson interactions via femtoscopic correlations

    Isabela M. Silvério🇧🇷 · Sandra S. Padula🇧🇷 · Gastão I. Krein🇧🇷

    Femtoscopy is a powerful tool that can be used to investigate the space-time dimensions of the region from which the particles are emitted. When applied to high energy collisions this method is sensitive not only to quantum statistics, but also to final state interactions, such as strong interactions between hadrons and Coulomb interactions when considering charged particles. In particular, this procedure is used to investigate the sensitivity of the strong interaction to different source sizes for mesons correlations.

    hep-phSciPost Phys.Proc.(2022)·1 citation
  3. 03*

    Mixed QCD--EW corrections to at the LHC

    Luca Buonocore🇨🇭

    We discuss about a recent computation of the mixed QCD--EW corrections to the hadroproduction of a massive charged lepton plus the corresponding neutrino through the Drell--Yan mechanism. The calculation, based on an extension of the subtraction formalism for heavy-quark production in next-to-next-to leading order QCD, includes for the first time all the real and virtual contributions due to initial- and final-state radiation, except for the finite part of the two-loop virtual correction, which is approximated in the pole approximation. We report results for the fiducial cross section and the transverse momentum spectrum of the charged lepton.

    hep-ph0 citations
  4. 04*

    Predictions of exclusive photoproduction at the LHC and future colliders

    Chris A. Flett🇫🇮 · Stephen P. Jones🇬🇧 · Alan D. Martin🇬🇧 · Misha G. Ryskin🇬🇧 · Thomas Teubner🇬🇧

    The cross section for exclusive ultraperipheral photoproduction at present and future colliders is determined using the low gluon PDF extracted from an analysis of exclusive measurements performed at HERA and the LHC. Predictions are given at next-to-leading order in collinear factorisation over a wide centre-of-mass energy range, calculated assuming the non-relativistic approximation for the wave function, and with skewing corrections incorporated.

    hep-phPRD(2022)·13 citations
  5. 05*

    The Nonsymmetric Flavor Transition Matrix and the Apparent P violation

    Shu-Jun Rong🇨🇳 · Ding-Hui Xu🇨🇳

    The leptonic mixing parameters of high precision and the next-generation neutrino telescopes make it possible to test new physics in the flavor transition of the high-energy astrophysical neutrinos(HAN). We introduce a nonsymmetric matrix to modify the predictions of the standard flavor transition matrix. It is constructed with the mixing matrix in vacuum and that at the source of the HAN. The mismatch of the mixing matrices results in the new expectation of the flavor ratio of the HAN at Earth. It also leads to a secondary effect called the apparent P violation (APV). The quantitative analyses of the new effects are performed with a moderate setup of the parameters at the source of the HAN. The correlations between the mixing parameters and the new predictions are shown. From the correlations, the dominant parameters determining the new-physics effects are identified.

    hep-phAdv.High Energy Phys.(2022)·2 citations
  6. 06*

    Suppression of thermal vorticity as an indicator of QCD critical point

    Sushant K. Singh🇮🇳 · Jan-e Alam🇮🇳

    We study the impact of the QCD critical point (CP) on the spin polarization of -hyperon generated by the thermal vorticity in viscous quark gluon plasma (QGP). The equations of the relativistic causal viscous hydrodynamics have been solved numerically in (3+1) dimensions to evaluate the thermal vorticity. The effects of the CP have been incorporated through the equation of state (EoS) and the scaling behavior of the transport coefficients. A significant reduction in the global polarization has been found as the CP is approached. A drastic change induced by the CP in the rapidity dependence of the spin polarization is observed which can be used as a signature of the CP.

    hep-phhep-exnucl-thEPJC(2023)·19 citations
  7. 07*

    Pion superfluid phase transition at finite isospin chemical potential

    Shu-Sheng Xu🇨🇳

    The pion superfluidity phase transition at and planes are studied in the framework of Dyson-Schwinger equations. The rainbow truncation and Gaussian effective gluon propagator are employed to calculate pion condensate, , as a function of at finite and . At ~MeV, the keeps zero when is less than a critical value . The at ~MeV agrees with the lattice QCD result. At the plane, the pion superfluid phase appears at low temperature and high isospin chemical potential region. At finite , varying with almost coincide for ~MeV. At plane, the pion superfluid phase appears at when ~MeV.

    hep-phEPJA(2021)·1 citation
  8. 09*

    Local Unitarity

    Zeno Capatti🇨🇭

    Within the Local Unitarity formalism, any physical cross-section is re-written in such a way that cancellations of infrared singularities between real and virtual contributions are realised locally. Consequently, phase-space and loop integrals are regulated locally without the need of any counter-terms or dimensional regularisation aside from those strictly needed to achieve ultraviolet regularisation. This Local Unitarity representation is especially suitable to direct Monte Carlo integration. As such, it offers a clear and direct path to automate the computation of fixed-order differential observables in Quantum Field Theories.

    hep-phhep-thSciPost Phys.Proc.(2022)·11 citations
  9. 10*

    Exploring the Sun's core with BabyIAXO

    Javier Galan (on behalf of the IAXO Collaboration)🇪🇸

    Axions are a natural consequence of the Peccei-Quinn mechanism, the most compelling solution to the strong-CP problem. Similar axion-like particles (ALPs) also appear in a number of possible extensions of the Standard Model, notably in string theories. Both, axions and ALPs, are very well motivated candidates for Dark Matter (DM), and they would be copiously produced at the suns core. A relevant effort during the last two decades has been the CAST experiment at CERN, the most sensitive axion helioscope to date. The International Axion Observatory (IAXO) is a large-scale 4th generation helioscope, and its primary physics goal is to extend further the search for solar axions or ALPs with a final signal to background ratio of about 5 orders of magnitude higher. We briefly review here the astrophysical hints and models that will be at reach while searching for solar axions within the context of the IAXO helioscope search program, and in particular the physics under reach for BabyIAXO, an intermediate helioscope stage towards the full IAXO.

    hep-phastro-ph.IMastro-ph.SRJ.Phys.Conf.Ser.(2021)·0 citations
  10. 11*

    HEJ 2.1: High-energy Resummation with Vector Bosons and Next-to-Leading Logarithms

    Jeppe R. Andersen🇬🇧 · James Black🇬🇧 · Helen Brooks🇦🇺 · Bertrand Ducloué🇬🇧 · Marian Heil🇬🇧 · Andreas Maier🇩🇪 · Jennifer M. Smillie🇬🇧

    We present version 2.1 of the High Energy Jets (HEJ) event generator for hadron colliders. HEJ is a Monte Carlo generator for processes at high energies with multiple well-separated jets in the final state. To achieve accurate predictions, conventional fixed-order perturbative QCD is supplemented with an all-order resummation of large high-energy logarithms. The new version 2.1 now supports processes with final-state leptons originating from a charged or neutral vector boson together with multiple jets, in addition to processes available in earlier versions. Furthermore, the all-order resummation is extended to include an additional gauge-invariant class of subdominant logarithmic corrections. HEJ 2.1 can be obtained from https://hej.hepforge.org.

    hep-phComput.Phys.Commun.(2022)·6 citations
  11. 12*

    Neutrino Masses and Hubble Tension via a Majoron in MFV

    Manuel González-López

    The recent tension between local and early measurements of the Hubble constant can be explained in a particle physics context. A mechanism is presented where this tension is alleviated due to the presence of a Majoron, arising from the spontaneous breaking of Lepton Number. The lightness of the active neutrinos is consistently explained. Moreover, this mechanism is shown to be embeddable in the Minimal (Lepton) Flavour Violating context, providing a correct description of fermion masses and mixings, and protecting the flavour sector from large deviations from the Standard Model predictions. A QCD axion is also present to solve the Strong CP problem. The Lepton Number and the Peccei-Quinn symmetries naturally arise in the Minimal (Lepton) Flavour Violating setup and their spontaneous breaking is due to the presence of two extra scalar singlets. The Majoron phenomenology is also studied in detail. Decays of the heavy neutrinos and the invisible Higgs decay provide the strongest constraints in the model parameter space.

    hep-phPoS(2022)·3 citations
  12. 13*

    Theory and phenomenology of Dirac neutrinos

    Salvador Centelles Chuliá🇪🇸

    In this thesis I discuss in some detail the possibility that neutrinos are Dirac. If this is indeed the case, some extra symmetries beyond the Standard Model gauge group need to be enforced in order to protect Diracness and the smallness of neutrino mass. These symmetries may have a deep connection with other physics sectors, like Dark Matter stability. I also review the general seesaw framework applied to Dirac neutrinos in a model-independent way thanks to the analysis of generalized Weinberg operators and give some simple, elegant UV complete examples both for seesaw variants and radiative mass models. Finally I study in some detail two models with very rich phenomenological predictions.

    hep-ph7 citations
  13. 14*

    NLO QCD corrections for off-shell

    Michele Lupattelli🇩🇪

    We present a full off-shell NLO QCD calculation of . Results are obtained using the HELAC-NLO Monte Carlo framework. We discuss a comparison to previous results and to experimental measurements. We also investigate the contribution of the initial states involving -quarks and we introduce two -jet tagging schemes.

    hep-phSciPost Phys.Proc.(2022)·0 citations
  14. 15*

    Prospects for Dark Matter signal discovery and model selection via timing information in a low-threshold experiment

    Riccardo Catena🇸🇪 · Vanessa Zema🇸🇪

    In the recent years, many low-threshold dark matter (DM) direct detection experiments have reported the observation of unexplained excesses of events at low energies. Exemplary for these, the experiment CRESST has detected unidentified events below an energy of about 200 eV - a result hampering the detector performance in the search for GeV-scale DM. In this work, we test the impact of nuclear recoil timing information on the potential for DM signal discovery and model selection on a low-threshold experiment limited by the presence of an unidentified background resembling this population of low-energy events. Among the different targets explored by the CRESST collaboration, here we focus on Al2O3, as a sapphire detector was shown to reach an energy threshold as low as 19.7 eV [1]. We test the ability of a low-threshold experiment to discover a signal above a given background, or to reject the spin-independent (SI) interaction in favour of a magnetic dipole (MD) coupling in terms of p-values. We perform our p-value calculations: 1) taking timing information into account; and 2) assuming that the latter is not available. By comparing the two approaches, we find that under our assumptions timing information has a marginal impact on the potential for DM signal discovery, while provides more significant results for the selection between the two models considered. For the model parameters explored here, we find that the p-value for rejecting SI-interactions in favour of a MD-coupling is about 0.11 when the experimental exposure is 460 g x year and smaller (about 0.06) if timing information is available. The conclusion on the role of timing information remains qualitatively unchanged for exposures as large as 1 kg x year. At the same time, our results show that a 90% C.L. rejection of SI-interactions in favour of a MD-coupling is within reach of an upgrade of the CRESST experiment [2].

    hep-phastro-ph.COJCAP(2022)·0 citations
  15. 16*

    Transverse momentum distributions in low-mass Drell-Yan lepton pair production at NNLO QCD

    R. Gauld🇳🇱 · A. Gehrmann-De Ridder🇨🇭 · T. Gehrmann🇨🇭 · E. W. N. Glover🇬🇧 · A. Huss🇨🇭 · I. Majer🇨🇭 · A. Rodriguez Garcia🇨🇭

    The production of lepton pairs at low invariant mass and finite transverse momentum resolves QCD dynamics at the boundary between the perturbative and non-perturbative domains. We investigate the impact of NNLO QCD corrections on these observables at energies corresponding to the BNL RHIC collider and to fixed-target experiments. Satisfactory perturbative convergence is observed in both cases. Only the collider data are found to be well-described by perturbative QCD, thus indicating the importance of non-perturbative effects in lepton-pair transverse momentum distributions at fixed target energies.

    hep-phhep-exPLB(2022)·17 citations
  16. 17*

    SMEFT analysis of the electroweak sector: challenges beyond dimension 6

    Raquel Gomez-Ambrosio🇮🇹 · Giacomo Magni🇳🇱

    In these proceedings we present the latest developments in our effort to include vector boson scattering (VBS) measurements into global SMEFT fits of LHC data. We present some updates to our initial study of arXiv:2101.03180 as well as comment on a possible road map for the inclusion of higher orders beyond dimension 6 in the SMEFT and on the interpretation of VBS data in other EFT frameworks.

    hep-phPoS(2022)·2 citations
  17. 18*

    Master integrals contributing to two-loop leading colour QCD helicity amplitudes for top-quark pair production in the gluon fusion channel

    Ekta Chaubey🇮🇹

    We present the master integrals relevant for computing the complete set of leading-colour analytic helicity amplitudes for top-quark pair production via gluon fusion at two-loops in QCD. We include corrections due to massive fermion loops which give rise to integrals involving elliptic curves. We also elaborate on the structure of singularities that play an important role in the numerical evaluation of the iterated integrals and their analytic continuation.

    hep-phhep-thSciPost Phys.Proc.(2022)·6 citations
  18. 19*

    Dark matter dilution scenarios in the early universe

    Arnab Chaudhuri🇷🇺 · Maxim Yu. Khlopov🇷🇺

    When the vacuum like energy of the Higgs potential within the standard model undergoes electroweak phase transition, an influx of entropy into the primordial plasma can lead to a significant dilution of frozen out dark matter density that was already present before the onset of the phase transition. The same effect can take place, if the early Universe was dominated by primordial black holes of small mass, evaporating before the period of Big Bang Nucleosynthesis. In this paper we calculate the dilution factor for the above mentioned scenarios.

    hep-phastro-ph.COInt.J.Mod.Phys.D(2021)·2 citations
  19. 20*

    Hadronic structure on the light-front I.\ Instanton effects and quark-antiquark effective potentials

    Edward Shuryak🇺🇸 · Ismail Zahed🇺🇸

    This is the first of a sequence of papers that address the non-perturbative origin of the central, and spin-dependent forces between quarks. Its main thrust is a focus on meson spectroscopy in the center of mass frame. We suggest a "dense instanton ensemble" model for the QCD vacuum, to explain the interquark forces in mesons, from quarkonia to heavy-light and light-light ones, to the extent it is possible. The sequels will show how to export these interactions to the light front, and derive the corresponding Hamiltonians and mesonic wavefunctions.

    hep-phPRD(2023)·32 citations
  20. 21*

    pySecDec as a tool for expansion by regions and loop amplitude evaluation

    Emilio Villa🇩🇪

    We present the new release of pySecDec, a toolbox for the evaluation of dimensionally regulated parameter integrals. The main new features consist of an automated way to perform expansions, based on the geometric approach to the method of expansion by regions, and a new algorithm to efficiently evaluate linear combinations of integrals as needed for the calculation of scattering amplitudes. The other new features are also summarised briefly.

    hep-phSciPost Phys.Proc.(2022)·0 citations
  21. 22*

    The as the dressed meson in a coupled-channels calculation

    Pablo G. Ortega🇪🇸 · Jorge Segovia🇪🇸 · David R. Entem🇪🇸 · Francisco Fernandez🇪🇸

    The recent discovery of the meson by the LHCb Collaboration has stimulated the analysis of meson-meson channels effects in the two-body quark-antiquark meson spectrum. This resonance, assigned to the radial excitation of the pseudoscalar meson, has a mass much lower than the predictions of naive quark models, which could indicate a non-negligible coupling which reduces its mass. Based on the importance of nearby meson-meson thresholds in the dynamics of P-wave mesons such as the and , in this work we perform a coupled-channels calculation including the , and channels, and study the impact of incorporating those channels in the mass of the bare . The coupling between two and four-quark sectors is done by means of the mechanism, with all the parameters constrained from previous studies of the heavy meson spectroscopy. The masses, widths and production line shapes of the resulting state are analyzed.

    hep-phPLB(2022)·22 citations
  22. 23*

    Scale Invariance and Dilaton Mass

    Ichiro Oda🇯🇵

    We consider a generic scale invariant scalar quantum field theory and its symmetry breakdown. Based on the dimension counting identity, we give a concise proof that dilaton is exactly massless at the classical level if scale invariance is broken spontaneously. On the other hand, on the basis of the generalized dimension counting identity, we prove that the dilaton becomes massive at the quantum level if scale invariance is explicitly broken by quantum anomaly. It is pointed out that a subtlety occurs when scale invariance is spontaneously broken through a scale invariant regularization method where the renormalization scale is replaced with the dilaton field. In this case, the dilaton remains massless even at the quantum level after spontaneous symmetry breakdown of scale symmetry, but when the massless dilaton couples non-minimally to the Einstein-Hilbert term and is applied for cosmology, it is phenomenologically ruled out by solar system tests unless its coupling to matters is much suppressed compared to the gravitational interaction.

    hep-thgr-qchep-ph4 citations
  23. 24*

    High resolution calibration of string network evolution

    J. R. C. C. C. Correia🇵🇹 · C. J. A. P. Martins🇵🇹

    The canonical velocity-dependent one-scale (VOS) model for cosmic string evolution contains a number of free parameters which cannot be obtained ab initio. Therefore it must be calibrated using high resolution numerical simulations. We exploit our state of the art graphically accelerated implementation of the evolution of local Abelian-Higgs string networks to provide a statistically robust calibration of this model. In order to do so, we will make use of the largest set of high resolution simulations carried out to date, for a variety of cosmological expansion rates, and explore the impact of key numerical choices on model calibration, including the dynamic range, lattice spacing, and the choice of numerical estimators for the mean string velocity. This sensitivity exploration shows that certain numerical choices will indeed have consequences for observationally crucial parameters, such as the loop chopping parameter. To conclude, we will also briefly illustrate how our results impact observational constraints on cosmic strings.

    astro-ph.COhep-phphysics.comp-ph1 citation
  24. 25*

    Ultralight dark matter or dark radiation cosmologically produced from infrared dressing

    Daniel Boyanovsky🇺🇸 · Mudit Rai🇺🇸 · Lisong Chen🇺🇸

    Infrared dressing of bosonic or fermionic heavy particles by a cloud of massless particles to which they couple is studied as a possible production mechanism of ultra light dark matter or dark radiation in a radiation dominated cosmology. We implement an adiabatic expansion valid for wavelengths much smaller than the Hubble radius combined with a non-perturbative and manifestly unitary dynamical resummation method to study the time evolution of an initial single heavy particle state. We find a striking resemblance to the process of particle decay: the initial amplitude of the single particle decays in time, not exponentially but with a power law with anomalous dimension featuring a crossover to as the heavy particle becomes non-relativistic in both bosonic and fermionic cases suggesting certain universality. At long time the asymptotic state is an entangled state of the heavy and massless particles. The entanglement entropy is shown to grow under time evolution describing the flow of information from the initial single particle to the final multiparticle state. The expectation value of the energy momentum tensor in the asymptotic state is described by two indpendent fluids each obeying covariant conservation, one of heavy particles and the other of relativistic (massless) particles (dark radiation). Both fluids share the same frozen distribution function and entropy as a consequence of entanglement.

    gr-qcastro-ph.COhep-phhep-th+1PRD(2021)·5 citations
  25. 26*

    Cosmic-Ray-Related Signals from Detectors in Space: the Spitzer/IRAC Si:As IBC Devices

    Brendan Hagan🇺🇸 · George Rieke🇺🇸 · Ori D. Fox🇺🇸 · Alberto Noriega-Crespo🇺🇸 · Dean C. Hines🇺🇸 · Misty Cracraft🇺🇸 · Macarena Garcia Marin🇺🇸

    We evaluate the hit rate of cosmic rays and their daughter particles on the Si:As IBC detectors in the IRAC instrument on the Spitzer Space Telescope. The hit rate follows the ambient proton flux closely, but the hits occur at more than twice the rate expected just from this flux. Toward large amplitudes, the size distribution of hits by single-charge particles (muons) follows the Landau Distribution. The amplitudes of the hits are distributed to well below the energy loss of a traditional ``average minimum-ionizing proton'' as a result of statistical fluctuations in the ionization loss within the detectors. Nonetheless, hits with amplitudes less than a few hundred electrons are rare; this places nearly all hits in an amplitude range that is readily identified given the read noises of modern solid-state detectors. The spread of individual hits over multiple pixels is dominated by geometric effects, i.e., the range of incident angles, but shows a modest excess probably due to: (1) showering and scattering of particles; (2) the energy imparted on the ionization products by the energetic protons; and (3) interpixel capacitance. Although this study is focused on a specific detector type, it should have general application to operation of modern solid-state detectors in space.

    astro-ph.IMhep-phPubl.Astron.Soc.Pac.(2021)·2 citations
  26. 27*

    Multigravity and the cosmological constant

    E. T. Tomboulis🇺🇸

    The possibility of flat metric solutions in the presence of arbitrary, in particular, Planck mass sized cosmological constants is investigated within multigravity theory, the ghost-free theory of rank-2 tensor fields comprising one massless and massive spin-2 fields. It is found that, indeed, for any , no matter how large, no flat solutions exist without fine-tuning parameters in the potential. For an infinite number of fields, however, flat solutions exist within an infinite-dimensional parameter space. Such a ground state may be viewed as a collective state that cannot be approximated by any finite .

    hep-thgr-qchep-ph0 citations
  27. 28*

    Anomalous spin polarization from turbulent color fields

    Berndt Müller🇺🇸 · Di-Lun Yang🇹🇼

    We study the important, yet widely overlooked, role of gluons for spin transport with a connection to local parity violation in quark gluon plasmas. We employ the formalism of quantum kinetic theory to quarks in weakly coupled quantum chromodynamics to derive the source terms for quark spin polarization. These source terms involve parity-odd correlators of dynamically generated color fields in near-equilibrium quark gluon plasmas and give rise to locally fluctuating axial charge currents. Our results provide a possible explanation for the spin alignment of vector mesons measured in high-energy nuclear collisions.

    nucl-thhep-phhep-thPRD(2022)·74 citations
  28. 29*

    Feynman integrals for binary systems of black holes

    Philipp Alexander Kreer🇩🇪 · Robert Runkel🇩🇪 · Stefan Weinzierl🇩🇪

    The initial phase of the inspiral process of a binary black-hole system can be described by perturbation theory. At the third post-Minkowskian order a two-loop double box graph, known as H-graph, contributes. In this talk we report how all master integrals of the H-graph with equal masses can be expressed up to weight four in terms of multiple polylogarithms. We also discuss techniques for the unequal mass case. The essential complication (and the focus of the talk) is the occurrence of several square roots.

    hep-thgr-qchep-phSciPost Phys.Proc.(2022)·3 citations
  29. 30*

    The electroweak Hamiltonian in the gradient flow formalism

    Robert Harlander🇩🇪 · Fabian Lange🇩🇪

    Over the last decade the gradient flow formalism has become an important tool for lattice simulations of Quantum Chromodynamics. It offers remarkable renormalization properties which pave the way for cross-fertilization between perturbative and lattice calculations. In this contribution we report on the construction of the flowed operator product expansion for the current-current operators of the electroweak Hamiltonian at NNLO QCD. This allows for simpler transformations between lattice and perturbative schemes and might reduce the uncertainties of theoretical predictions for low-energy flavor observables.

    hep-lathep-phPoS(2022)·1 citation
  30. 31*

    Structure-Dependent Electromagnetic Finite-Size Effects

    Matteo Di Carlo🇬🇧 · Maxwell T. Hansen🇬🇧 · Nils Hermansson-Truedsson🇨🇭 · Antonin Portelli🇬🇧

    We present a model-independent and relativistic approach to analytically derive electromagnetic finite-size effects beyond the point-like approximation. The key element is the use of electromagnetic Ward identities to constrain vertex functions, and structure-dependence appears via physical form-factors and their derivatives. We apply our general method to study the leading finite-size structure-dependence in the pseudoscalar mass (at order ) as well as in the leptonic decay amplitudes of pions and kaons (at order ). Knowledge of the latter is essential for Standard Model precision tests in the flavour physics sector from lattice simulations.

    hep-lathep-phhep-thPoS(2024)·0 citations
  31. 32*

    Self-force on a charged particle in an external scalar field

    Adam Noble🇨🇦 · David A. Burton🇬🇧 · Lauren Docherty🇬🇧 · Dino A. Jaroszynski🇬🇧

    A charged particle subject to strong external forces will accelerate, and so radiate energy, inducing a self-force. This phenomenon remains contentious, but advances in laser technology mean we will soon encounter regimes where a more complete understanding is essential. The terms "self-force" and "radiation reaction" are often used synonymously, but reflect different aspects of the recoil force. For a particle accelerating in an electromagnetic field, radiation reaction is usually the dominant self-force, but in a scalar field this is not the case, and the total effect of the self-force can be anti-frictional. Aspects of this self-force can be recast in terms of spacetime geometry, and this interpretation illuminates the long-standing enigma of a particle radiating while experiencing no self-force.

    physics.class-phgr-qchep-phNew J.Phys.(2021)·10 citations
  32. 33*

    Finite Callan-Symanzik renormalisation for multiple scalar fields

    Sander Mooij🇨🇭 · Mikhail Shaposhnikov🇨🇭

    We study a finite, divergence free approach to renormalisation originally proposed in the early '70s by Blaer and Young, and Callan. It is based on equations similar to the Callan-Symanzik equations, and introduced in the context of theory. We generalise this method to the case of two interacting scalar fields, with obvious generalisation to an arbitrary number of fields.

    hep-thhep-phNPB(2023)·12 citations
  33. 34*

    CME search at STAR

    Yu Hu (for the STAR Collaboration)🇨🇳

    The hot and dense medium produced in relativistic heavy-ion collisions has been conjectured to be accompanied by an axial charge asymmetry that may lead to a separation of electric charges in the direction of the extremely strong magnetic field, also known as the Chiral Magnetic Effect (CME). The measurement of azimuthal correlator () with respect to the spectator plane, gives us an opportunity to measure the possible CME fraction beyond the flow background. Preliminary results using this approach with combined Au+Au collisions at 200 GeV and U+U at 193 GeV show at . Meanwhile, the observability of CME has been conjectured to be dependent on due to changes in the lifetime of the magnetic field, the strengths of CME signal and non-CME background. At lower energies, the Event Plane Detector (EPD) installed in the year 2018 provides a unique capability for CME search. The background scenario test at Au+Au 27 GeV by using with respect to TPC and the new installed EPD shows a consistency with no-CME scenario in the current statistics. The method of the ongoing isobar blind analysis, and the latest sensitivity check with the event-by-event AVFD model on the different observables between Ru+Ru and Zr+Zr are also briefly discussed.

    nucl-exhep-phnucl-thEPJ Web Conf.(2022)·5 citations
  34. 35*

    Large- constraints for elastic dark matter-light nucleus scattering in pionless effective field theory

    Thomas R. Richardson🇺🇸 · Xincheng Lin🇺🇸 · Son T. Nguyen🇺🇸

    Recent proposals for the use of light nuclei as dark matter direct detection targets necessitate a strong theoretical understanding of the nuclear physics involved. We perform relevant calculations for dark matter-light nucleus scattering in a combined pionless effective field theory and large- expansion, where is the number of quark colors. We include a general set of one-nucleon currents that have been used in other effective theories, as well as novel two-nucleon contact currents. First, we obtain constraints for the relative sizes of the dark matter couplings to the one- and two-nucleon currents through the large- expansion. Then, we use these constraints to make predictions for the relative sizes of spin-dependent and spin-independent cross sections for dark matter scattering off of a nucleon, a deuteron, a triton, and helium-3.

    nucl-thhep-phPRC(2022)·9 citations
  35. 36*

    A Step in Understanding the Hubble Tension

    Daniel Aloni🇺🇸 · Asher Berlin🇺🇸 · Melissa Joseph🇺🇸 · Martin Schmaltz🇺🇸 · Neal Weiner🇺🇸

    As cosmological data have improved, tensions have arisen. One such tension is the difference between the locally measured Hubble constant and the value inferred from the cosmic microwave background (CMB). Interacting radiation has been suggested as a solution, but studies show that conventional models are precluded by high- CMB polarization data. It seems at least plausible that a solution may be provided by related models that distinguish between high- and low- multipoles. When interactions of strongly-coupled radiation are mediated by a force-carrier that becomes non-relativistic, the dark radiation undergoes a "step" in which its relative energy density increases as the mediator deposits its entropy into the lighter species. If this transition occurs while CMB-observable modes are inside the horizon, high- and low- peaks are impacted differently, corresponding to modes that enter the horizon before or after the step. These dynamics are naturally packaged into the simplest supersymmetric theory, the Wess-Zumino model, with the mass of the scalar mediator near the eV-scale. We investigate the cosmological signatures of such "Wess-Zumino Dark Radiation" (WZDR) and find that it provides an improved fit to the CMB alone, favoring larger values of . If supernovae measurements from the SH0ES collaboration are also included in the analysis, the inferred value of is yet larger, but the preference for dark radiation and the location of the transition is left nearly unchanged. Utilizing a standardized set of measures, we compare to other models and find that WZDR is among the most successful at addressing the tension and the best of those with a Lagrangian formulation.

    astro-ph.COhep-phPRD(2022)·118 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.