Thu·May 1, 2025Thursday·May 1, 2025

1. 01*

   Probing the Axion-Nucleon Coupling with Supergiant Stars

   Francisco R. Candón🇩🇪 · Pablo Casaseca🇪🇸 · Maurizio Giannotti🇪🇸 · Mathieu Kaltschmidt🇪🇸 · Jaime Ruz🇩🇪 · Julia K. Vogel🇩🇪

   A finite axion-nucleon coupling enables the production of axions in stellar environments via the thermal excitation and subsequent de-excitation of the ${}^{57}$Fe isotope. Given its low-lying excited state at 14.4 keV, ${}^{57}$Fe can be efficiently excited in the hot cores of supergiant stars, possibly leading to axions emission. The conversion of these axions into photons in the Galactic magnetic field results in a characteristic 14.4 keV line, potentially detectable by hard X-ray telescopes such as NASA's Nuclear Spectroscopic Telescope Array (NuSTAR). In this work, we present the first constraints on axion-nucleon couplings derived from \textsc{NuSTAR} observations of Betelgeuse and discuss the potential insights that could be gained from detecting this line in other nearby supergiants. Our results establish significantly more stringent bounds than those obtained from solar observations, setting a limit of $|g_{a\gamma }{g}_{aN}^{\mathrm{eff}}|<(1.2-2.7)\times 10^{-20}$ GeV${}^{-1}$ for $m_a\lesssim 10^{-10}$ eV.

   hep-phastro-ph.HEastro-ph.SRPRD(2025)·7 citations
2. 02*

   Universal Equilibration Condition for Heavy Quarks

   Krishna Rajagopal🇺🇸 · Bruno Scheihing-Hitschfeld🇺🇸 · Urs Achim Wiedemann🇨🇭

   Kinetic equilibration at late times is physically required for heavy particles in a finite temperature medium. In Fokker-Planck dynamics, it is ensured by the Einstein relation between the drag and longitudinal momentum diffusion coefficients. However, in certain gauge field theories, this relation is violated at any nonzero heavy quark velocity. Recent work in strongly coupled $\mathcal{N}=4$ SYM gauge theory shows that the Kolmogorov equation for the heavy quark phase space distribution (that reduces to Fokker-Planck form upon truncating the momentum transfer probability distribution to second moments) does equilibrate even though the Fokker-Planck equation does not. Going beyond these (to date theory-specific) insights, we derive a universal equilibration condition for the kernel of the Kolmogorov equation and, consequently, for the momentum transfer probability distribution that holds in any quantum field theory with any coupling strength. This condition, which is the generalization of the Einstein relation to quantum field theories which feature non-Gaussian fluctuations, reveals that the asymmetry between energy loss and energy gain in the momentum transfer probability distribution takes a simple, theory-independent, form.

   hep-phhep-thnucl-thPRL(2025)·14 citations
3. 03*

   Quarkonium suppression in strongly coupled plasmas

   Bruno Scheihing-Hitschfeld🇺🇸 · Xiaojun Yao🇺🇸

   Suppression of open heavy quarks and quarkonia in heavy-ion collisions are among the most informative probes of quark-gluon plasma (QGP). Interpreting the full wealth of data obtained from the collision events requires a precise theoretical understanding of the evolution of heavy quarks and quarkonia as they propagate through a strongly coupled plasma. Such calculations require the evaluation of a gauge-invariant correlator of chromoelectric fields. This chromoelectric correlator encodes all the characteristics of QGP that the dissociation and recombination dynamics of quarkonium are sensitive to, which is to say can in principle measure. We review its distinctive qualitative features at weak coupling in QCD up to next-to-leading order and at strong coupling in $\mathcal{N}=4$ SYM using the AdS/CFT correspondence, as well as its formulation in Euclidean QCD. Furthermore, we report on recent progress in applying our results to the calculation of the final quarkonium abundances after propagating through a cooling droplet of QGP, which illustrates how we may learn about QGP from quarkonium measurements. We devote special attention to how the presence of a strongly coupled plasma modifies the transport description of quarkonium, in comparison to approaches that rely on weak coupling approximations to describe quarkonium dissociation and recombination.

   hep-phnucl-thEPJ Web Conf.(2025)·0 citations
4. 04*

   Electroweak Phase Transition and Bubble Wall Velocity in Local Thermal Equilibrium

   Carlo Branchina🇮🇹 · Angela Conaci🇮🇹 · Stefania De Curtis🇮🇹 · Luigi Delle Rose🇮🇹

   The dynamics of the electroweak phase transition in the early universe has profound implications for cosmology and particle physics. We systematically study the steady-state dynamics of bubble walls in scenarios where the transition is first order within three representative beyond the Standard Model frameworks, characterised by the presence of an additional scalar in different electroweak representations. Focusing on the local thermal equilibrium regime, we numerically solve the coupled scalar and hydrodynamic equations to extract key properties of the phase transition front: the wall velocity, width, plasma and field profiles. Remarkably, we find a near-universal behaviour across models when expressed in terms of thermodynamic quantities, that can be captured by simple fitting functions, useful for phenomenological applications. These results also provide an upper bound on the bubble velocity and represent the first necessary step for the full inclusion of out-of-equilibrium effects.

   hep-phastro-ph.COhep-thPRD(2025)·28 citations
5. 05*

   Interplay of $95$ GeV Diphoton Excess and Dark Matter in Supersymmetric Triplet Model

   Zetian Li🇨🇳 · Ning Liu🇨🇳 · Bin Zhu🇨🇳

   The decay of the Higgs boson and the nature of dark matter remain fundamental challenges in particle physics. We investigate the $95$ GeV diphoton excess and dark matter within the framework of the triplet-extended Minimal Supersymmetric Standard Model (TMSSM). In this model, an additional Hypercharge $Y=0$, $SU(2{)}_L$ triplet superfield is introduced. Mixing between the triplet and doublet Higgs states enhances the diphoton signal strength of the $95$ GeV Higgs boson, resulting in ${\mu }_{\gamma \gamma }^{\text{CMS+ATLAS}}=0.24_{-0.08}^{+0.09}$, which is consistent with experimental observations. This enhancement arises primarily from charged Higgs loop contributions. Additionally, the model accommodates viable dark matter candidates in the form of a bino-dominated neutralino. The relic density is reduced to the observed value through resonance-enhanced annihilation via the Higgs portal or co-annihilation with the triplino or higgsino. This reduction remains consistent with constraints from direct and indirect detection experiments. A comprehensive parameter scan demonstrates that the TMSSM can simultaneously explain the $95$ GeV diphoton excess, the observed $125$ GeV Higgs mass, and the dark matter relic density, establishing a compelling and theoretically consistent framework.

   hep-phCPC(2026)·8 citations
6. 06*

   Analysis of ${\Sigma }^{\ast }$ via isospin selective reaction $K_{L}p\to {\pi }^{+}{\Sigma }^0$

   Dan Guo🇨🇳 · Jun Shi🇨🇳 · Igor Strakovsky🇺🇸 · Bing-Song Zou🇨🇳

   The isospin-selective reaction $K_{L}p\to {\pi }^{+}{\Sigma }^0$ provides a clean probe for investigating $I=1$ ${\Sigma }^{\ast }$ resonances. In this work, we perform an analysis of this reaction using an effective Lagrangian approach for the first time, incorporating the well-established $\Sigma (1189)1/2^{+}$, $\Sigma (1385)3/2^{+}$, $\Sigma (1670)3/2^{-}$, $\Sigma (1775)5/2^{-}$ states, while also exploring contributions from other unestablished states. By fitting the available differential cross section and recoil polarization data, adhering to partial-wave phase conventions same as PDG, we find that besides the established resonances, contributions from $\Sigma (1660)1/2^{+}$, $\Sigma (1580)3/2^{-}$ and a ${\Sigma }^{\ast }(1/2^{-})$ improve the description. Notably, a ${\Sigma }^{\ast }(1/2^{-})$ resonance with mass around 1.54 GeV, consistent with $\Sigma (1620)1/2^{-}$, is found to be essential for describing the data in this channel, a stronger indication than found in previous analyses focusing on $\pi \Lambda$ final states. While providing complementary support for $\Sigma (1660)1/2^{+}$ and $\Sigma (1580)3/2^{-}$, our results highlight the importance of the $\Sigma (1620)1/2^{-}$ region in $K_{L}p\to {\pi }^{+}{\Sigma }^0$. Future high-precision measurements are needed to solidify these findings and further constrain the ${\Sigma }^{\ast }$ spectrum.

   hep-phnucl-thPRD(2025)·5 citations
7. 07*

   Prediction of $p\bar{\Omega }$ states and femtoscopic study

   Ye Yan🇨🇳 · Qi Huang🇨🇳 · Qian Wu🇨🇳 · Hongxia Huang🇨🇳 · Jialun Ping🇨🇳

   Inspired by recent researches on the $p\Omega$ and $p\bar{\Lambda }$ systems, we investigate the $p\bar{\Omega }$ systems within the framework of a quark model. Our results show that the attraction between a nucleon and $\bar{\Omega }$ is slightly stronger than that between a nucleon and $\Omega$, suggesting that the $p\bar{\Omega }$ system is more likely to form bound states. The dynamic calculations indicate that the $p\bar{\Omega }$ systems with both $J^P=1^{-}$ and $2^{-}$ can form bound states, with binding energies deeper than those of the $p\Omega$ systems with $J^P=2^{+}$. The scattering phase shift and scattering parameter calculations also support the existence of $p\bar{\Omega }$ states. Additionally, we discuss the behavior of the femtoscopic correlation function for the $p\bar{\Omega }$ pairs for the first time. Considering the significant progress in experimental measurements of the correlation function of the $p\Omega$ system, the further study of the $p\bar{\Omega }$ systems using femtoscopic techniques will be a very valuable work.

   hep-phhep-exhep-lathep-thNucl.Sci.Tech.(2026)·4 citations
8. 08*

   A radiative neutrino mass model with leptoquarks under non-holomorphic modular $A_4$ symmetry

   Takaaki Nomura🇨🇳 · Hiroshi Okada🇨🇳 · Xing-Yu Wang🇨🇳

   We investigate a radiative seesaw model with two leptoquarks under non-holomorphic modular $A_4$ symmetry. The leptons and quarks belong to non-trivial representations of the modular $A_4$ and the structures of their mass matrices are restricted. Neutrino masses are generated at one-loop level via leptoquark inside loop diagram where structures of relevant Yukawa interactions are determined by the modular $A_4$ symmetry. We scan the free parameters in the model and try to fit all the observed data for both lepton and quark sectors. For allowed parameters, we show some predictions regarding neutrino observables such as sum of neutrino mass and neutrinoless double beta decay.

   hep-phJHEP(2025)·18 citations
9. 09*

   Evidence for the existence of a flavor-sextet charmed meson?

   Feng-Kun Guo🇨🇳 · Bing-Song Zou🇨🇳

   Recently, the LHCb Collaboration reported a signal for a new resonance in the $D_s^{+}{\pi }^{\pm }$ invariant mass distribution in the decays $B\to {\bar{D}}^{(\ast )}{D}_s^{+}{\pi }^{+}{\pi }^{-}$ (arXiv:2411.03399). This could be a direct observation of an SU(3) flavor-sextet charmed meson with $J^P=0^{+}$. Such an SU(3) multiplet, is beyond the conventional quark-antiquark picture, and thus a verification of this observation is important.

   hep-phhep-exSci.Bull.(2025)·2 citations
10. 10*

    Domain Wall as Cosmological Oscillator

    Bo-Qiang Lu🇨🇳

    In this study, we examine the domain wall within the framework of a cosmological harmonic oscillator. We investigate the interaction between the domain wall and a periodic background field, which can induce perturbations in the oscillatory behavior of the wall. We propose a novel mechanism for resolving the domain wall problem through the phenomenon of resonant oscillation. Resonant oscillation occurs when the frequency of the external driving force aligns with the intrinsic frequency of the domain wall. This synchrony can significantly amplify the amplitude of the oscillation. If the amplitude of oscillation exceeds a predetermined critical deformation threshold, the domain wall may be deconstructed. Furthermore, we demonstrate that this mechanism remains valid in models that preserve discrete symmetry.

    hep-phgr-qchep-thJHEP(2026)·0 citations
11. 11*

    Plausible Indication of Gamma-Ray Absorption by Dark Matter in NGC 1068

    Gonzalo Herrera🇺🇸

    NGC 1068 is the brightest extragalactic source in high-energy neutrinos as seen by IceCube, yet the accompanying gamma-ray flux is orders of magnitude weaker. It has been argued that this indicates that the bulk of neutrinos and gamma rays are emitted in the innermost vicinity of the central supermassive black hole, which is transparent to neutrinos, but opaque to gamma rays. Even in such extreme scenarios for the acceleration of cosmic rays, astrophysical models typically overestimate the low-energy gamma-ray flux and/or require some fine-tuning in the physical parameters. Here we suggest instead that the dark matter surrounding the supermassive black hole may absorb the gamma rays, inducing the observed deficit. We show that for a dark matter-photon scattering cross section in the range ${\sigma }_{\mathrm{DM}-\gamma }/m_{\mathrm{DM}}\simeq 10^{-28}-10^{-30}$ cm${}^2$/GeV, Fermi-LAT measurements can be well reconciled with IceCube data. We also present some simple particle physics examples that achieve the correct spectral energy dependence while respecting complementary constraints.

    hep-phastro-ph.COastro-ph.HEPhys.Dark Univ.(2025)·6 citations
12. 12*

    Dark-technicolour at colliders

    Gauhar Abbas🇮🇳 · Vartika Singh🇮🇳 · Neelam Singh🇮🇳

    We demonstrate that QCD-like gauge dynamics can be consistently embedded within the Dark Technicolor paradigm by invoking the extended Most Attractive Channel hypothesis, thereby revitalizing conventional technicolor scenarios. In this framework, the Higgs mass is generated dynamically while remaining consistent with electroweak precision tests, including constraints from the $S$ parameter. The flavor problem is resolved by incorporating the Standard Hierarchical VEVs Model, whereas a simple Froggatt--Nielsen construction is shown to be incompatible. Couplings of techni-hadrons such as ${\rho }_{\mathrm{TC}}$ and ${\eta }_{\mathrm{TC}}^{\prime }$ to Standard Model fermions are highly suppressed, leading to negligible direct fermionic signatures. Nevertheless, DTC mesons remain testable at the HL-LHC, HE-LHC, and future 100~TeV collider, with promising discovery channels including $\bar{b}b$, ${\tau }^{+}{\tau }^{-}$, $t\bar{t}$, and $\gamma \gamma$.

    hep-phhep-exEPJC(2026)·8 citations
13. 13*

    Hard probes and nuclear PDFs

    Petja Paakkinen🇫🇮

    A mini-review on the status of global analyses of nuclear parton distribution functions is given, focusing on the most relevant constraints for the hard-probes phenomenology in ultra-relativistic heavy-ion collisions.

    hep-phEPJ Web Conf.(2025)·0 citations
14. 14*

    Prospects for new glueballs and exotics searches

    Jean-Marie Frere🇧🇪

    Glueballs and Hybrids are solid predictions of QCD, but none have this far been identified in an undisputable way. We list several strategies, including the very promising search for "cascade" decays of glueballs and hybrids into each others, and mention the yet under-exploited sources in heavy ion collisions

    hep-phPoS(2025)·1 citation
15. 15*

    Leptogenesis, $0\nu \beta \beta$ and lepton flavor violation in modular left-right asymmetric model with polyharmonic $Maa\beta$ forms

    Bhabana Kumar🇮🇳 · Mrinal Kumar Das🇮🇳

    In the absence of supersymmetry, modular forms need not be holomorphic functions of the modulus $\tau$. Using this idea, we construct a non-supersymmetric framework using polyharmonic $Maa\beta$ forms. In this approach, the Yukawa coupling is no longer strictly holomorphic in $\tau$ but instead incorporates both holomorphic and non-holomorphic components. We realize a non-supersymmetric, left-right asymmetric model based on the ${\Gamma }_3$ modular group, where the active neutrino masses are generated via an extended inverse seesaw mechanism. The model successfully predicts the sum of neutrino masses below the current experimental bound and accommodates neutrino mixing angles within the $3\sigma$ range. Given its strong predictive power in neutrino oscillation parameters, we further explore its implications for beyond Standard Model (BSM) phenomena, including neutrinoless double beta ($0\nu \beta \beta$) decay, lepton flavor violation (LFV), and baryogenesis via leptogenesis (BAU). Our findings indicate that the model predicts an effective Majorana mass and LFV branching ratios consistent with experimental constraints while also providing a viable explanation for the observed baryon asymmetry through resonant leptogenesis.

    hep-phJHEP(2025)·12 citations
16. 16*

    Hadronic tau decays

    Antonio Rodríguez-Sánchez🇪🇸

    We give a pedagogical introduction to the rich phenomenology of hadronic tau decays. These decays provide a unique window into the interplay of electroweak and strong interactions at low energies, as they occur primarily via $W$ exchange after the electroweak quark current hadronizes. In this manuscript, we summarize the basic ingredients required to perform precision physics studies in this sector. We detail the derivation of the different distributions within the Standard Model, discuss how to parametrize the non-perturbative QCD dynamics, and present methods commonly used to achieve clean theoretical predictions. Additionally, we briefly review how these distributions generalize in the presence of relatively heavy particles from beyond the Standard Model. This overview thus aims to serve as a useful starting point for readers interested in understanding how the only lepton capable of decaying into hadrons does so.

    hep-phhep-ex6 citations
17. 17*

    Thermoelectric Thomson coefficient of quark-gluon plasma in the presence of a time-varying magnetic field

    Kamaljeet Singh🇮🇳 · Raghunath Sahoo🇮🇳

    Heavy-ion collision experiments such as the Large Hadron Collider and the Relativistic Heavy Ion Collider offer a unique platform to study several key properties of the quark-gluon plasma (QGP), a deconfined state of strongly interacting matter. Quarks, being the electrically charged particles, can induce an electric current in the medium in response to the temperature gradients. Hence, the QGP medium can behave like a thermoelectric medium. The thermoelectric coefficients, such as the Seebeck and Thomson coefficients, can help us to understand the intricate transport phenomenon of the medium. In peripheral collisions, the intense, transient, and time-dependent magnetic field created due to spectator protons significantly influences the thermoelectric properties of the QGP medium, affecting the charge and heat transport. This work uses the quasi-particle model to calculate the Thomson coefficient in QGP. The Thomson effect, describing the continuous heating or cooling of the charge-carrying medium in the presence of temperature gradients, remains largely unexplored in QGP. The Seebeck effect, which relates temperature gradients to induced electric fields, has been widely studied in the literature. For the first time, we calculate the magneto-Thomson and transverse Thomson coefficients. We have studied their dependence on temperature, baryon chemical potential, center of mass energy, and time-dependent magnetic field with different decay parameters. The transverse Thomson effect originates due to the presence of the Nernst effect in the presence of a magnetic field. Our results provide new insights into the higher-order thermoelectric transport properties of the QGP medium in the context of heavy-ion collisions.

    hep-phhep-exhep-thnucl-ex+1PRD(2025)·7 citations
18. 18*

    Jet Modification and Medium Response -- Theory Overview

    Daniel Pablos🇪🇸

    This text contains a summary and personal perspective on the current status and challenges of jet quenching physics as portrayed by the presentations delivered at the 12th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions (Hard Probes 2024) which took place in September 2024 in Nagasaki, Japan.

    hep-phEPJ Web Conf.(2025)·0 citations
19. 19*

    Cosmological-model independent limits on photon mass from FRB and SNe data

    Thais Lemos🇧🇷 · Rodrigo Gonçalves🇧🇷 · Joel Carvalho🇧🇷 · Jailson Alcaniz🇧🇷

    Electromagnetic emissions from astrophysical sources at cosmological distances can be used to estimate the photon mass, $m_{\gamma }$. In this paper, we combine measurements of the dispersion measure ($\mathrm{DM}$) of fast radio bursts (FRB) with the luminosity distance from type Ia supernovae (SNe) to investigate update constraints on the photon rest mass. We derive the expression of $\mathrm{DM}$ dependence concerning a non-vanishing photon mass from a cosmological-model independent approach and constrain the parameter $m_{\gamma }$ from measurements of 68 well-localized FRBs and 1048 SNe data from the Pantheon compilation. We consider two scenarios for the baryon fraction in the intergalactic medium ($f_{\mathrm{IGM}}$): one where the value is fixed according to recent reports and another where it is treated as a free parameter, $f_{\mathrm{IGM}}=f_{\mathrm{IGM},0}$. In the latter case, we find $m_{\gamma }=(29.4_{-15.5}^{+5.80})\times 10^{-51}$ kg, at $1\sigma$ level. Our results also demonstrate an anticorrelation between $f_{\mathrm{IGM}}$ and $m_{\gamma }$, which highlights the importance of analyzing a larger sample of FRBs for a more comprehensive understanding of their properties.

    ↳ astro-ph.COastro-ph.HEhep-phJCAP(2025)·8 citations
20. 20*

    Do QGP Droplets Drive Anisotropy in Small Systems? Insights from RHIC and the LHC

    Roy A. Lacey (Department of Chemistry, Stony Brook University, Stony Brook, NY, USA)🇺🇸

    Azimuthal anisotropy scaling functions for identified mesons and baryons are analyzed in large (Pb+Pb at $\sqrt{s_{NN}}=2.76$ and 5.02 TeV, Au+Au at $\sqrt{s_{NN}}=200$ GeV), intermediate (Cu+Cu at $\sqrt{s_{NN}}=200$~GeV), and small (p+Pb at $\sqrt{s_{NN}}=5.02$ and 8.16 TeV, p+Au, d+Au, and ${}^3$He+Au at $\sqrt{s_{NN}}=200$ GeV) collision systems. The scaling functions' fidelity supports a hydrodynamic-like origin for anisotropies in the flow-dominated regime. Central Pb+Pb, Au+Au, and Cu+Cu reflect QGP-driven expansion with strong radial flow and significant jet quenching, while peripheral Pb+Pb and Cu+Cu exhibit hadronic-dominated dynamics. In contrast, central RHIC small systems show hadronic-dominated behavior, with strong re-scattering, negligible radial flow, and suppressed jet quenching, following the hierarchy p+Au $>$ d+Au $>$ ${}^3$He+Au. At the LHC, ultra-central p+Pb collisions display enhanced radial flow, reduced re-scattering, and small but nonzero jet quenching. Scaling violations at high $p_T$ reflect partial suppression of partonic energy loss. These findings demonstrate that QGP-like behavior in small systems depends sensitively on both system size and beam energy, and establish the scaling framework as a robust diagnostic of collectivity and medium properties across diverse collision conditions.

    ↳ hep-exhep-phhep-thnucl-ex1 citation
21. 21*

    Impact of isospin asymmetric nuclear medium on pseudoscalar and vector $B$ mesons

    Tanisha🇮🇳 · Satyajit Puhan🇮🇳 · Navpreet Kaur🇮🇳 · Arvind Kumar🇮🇳 · Harleen Dahiya🇮🇳

    In this study, using the light-front quark model, we examine how an isospin asymmetric nuclear medium affects the properties of pseudoscalar ($B^{+},B^0$) and vector ($B^{\ast +},B^{\ast 0}$) mesons under different temperature values and degrees of isospin asymmetry. To simulate the in-medium modifications of the constituent quark masses, we employ the chiral SU(3) quark mean field model. Our analysis focuses on evaluating the effective masses, weak decay constants, and distribution amplitudes (DAs) of $B$ mesons in isospin-asymmetric nuclear matter. The calculated vacuum values of the $B$ meson masses and decay constants show good agreement with existing experimental data, validating our approach to study the medium effects within the same framework.

    ↳ nucl-thhep-phNPA(2026)·2 citations
22. 22*

    The Muon Collider

    Carlotta Accettura🇨🇭 · Simon Adrian🇩🇪 · Rohit Agarwal🇺🇸 · Claudia Ahdida🇨🇭 · Chiara Aime'🇮🇹 · Avni Aksoy🇹🇷 · Gian Luigi Alberghi🇮🇹 · Siobhan Alden🇬🇧 · Luca Alfonso🇮🇹 · Muhammad Ali🇮🇹 · Anna Rita Altamura🇮🇹 · Nicola Amapane🇮🇹 and 446 other authors

    Muons offer a unique opportunity to build a compact high-energy electroweak collider at the 10 TeV scale. A Muon Collider enables direct access to the underlying simplicity of the Standard Model and unparalleled reach beyond it. It will be a paradigm-shifting tool for particle physics representing the first collider to combine the high-energy reach of a proton collider and the high precision of an electron-positron collider, yielding a physics potential significantly greater than the sum of its individual parts. A high-energy muon collider is the natural next step in the exploration of fundamental physics after the HL-LHC and a natural complement to a future low-energy Higgs factory. Such a facility would significantly broaden the scope of particle colliders, engaging the many frontiers of the high energy community. The last European Strategy for Particle Physics Update and later the Particle Physics Project Prioritisation Panel in the US requested a study of the muon collider, which is being carried on by the International Muon Collider Collaboration. In this comprehensive document we present the physics case, the state of the work on accelerator design and technology, and propose an R\&D project that can make the muon collider a reality.

    ↳ physics.acc-phhep-exhep-phphysics.ins-det103 citations
23. 23*

    Baryon asymmetry from higher-order matter contributions in gravity

    David S. Pereira🇵🇹 · Francisco S.N. Lobo🇵🇹 · José Mimoso🇵🇹

    We investigate the observed asymmetry between matter and antimatter by incorporating higher-order matter contributions in gravity, specifically analyzing gravitational baryogenesis within the framework of $f(R,{\mathcal{T}}^2)$ gravity, where $R$ is the Ricci scalar and ${\mathcal{T}}^2\equiv T_{\mu \nu }{T}^{\mu \nu }$. We further explore the impact of high-order matter contributions by considering an interaction term analogous to those in gravitational and spontaneous baryogenesis, constructed using ${\mathcal{T}}^2$. The cutoff energy scale of the new interaction term is presented and its implications to Big Bang Nucleosynthesis (BBN) are discussed. The properties and implications of this term are analyzed within the frameworks of General Relativity and $f(R,{\mathcal{T}}^2)$ gravity. Furthermore, a connection to Big Bang Nucleosynthesis (BBN) is established, providing an observational constraint on the functional form of $f(R,{\mathcal{T}}^2)$. By introducing ${\mathcal{T}}^2$ into the gravitational action, we propose that these modifications could significantly influence the early Universe's dynamics, thereby altering the conditions necessary for baryogenesis to occur.

    ↳ gr-qchep-phPLB(2025)·7 citations
24. 24*

    Double nuclear modification factor in relativistic heavy ion collisions

    A.S. Chernyshov🇷🇺 · I.P. Lokhtin🇷🇺 · A.M.Snigirev🇷🇺

    The hypothesis of the factorization of the double nuclear modification factor in relativistic heavy ion collisions is tested for different types of final-state hadrons within the HYDJET++ model. The results demonstrate that this factorization holds reasonably well at moderately high transverse momenta, provided that the effects of double parton scattering can be small or neglected.

    ↳ nucl-thhep-phnucl-exJETP Lett.(2025)·0 citations
25. 25*

    Dilepton emission in heavy ion collisions and chemical equilibrium of QCD matter

    Xiang-Yu Wu🇨🇦 · Lipei Du🇨🇦 · Charles Gale🇨🇦 · Sangyong Jeon🇨🇦

    We study thermal dilepton production and anisotropic flow in Pb+Pb collisions at $\sqrt{s_{NN}}=5.02\mathrm{TeV}$ using next-to-leading-order (NLO) thermal QCD dilepton emission rates. A hybrid model (IP-Glasma+\kompost+MUSIC+UrQMD) simulates the collision evolution. The role of the pre-equilibrium stage in dilepton observables is examined. We also explore how chemical equilibrium in QCD matter affect dilepton observables.

    ↳ nucl-thhep-phEPJ Web Conf.(2025)·0 citations
26. 26*

    Holography and Causality in the Karch-Randall Braneworld

    Hao Geng🇺🇸 · Lisa Randall🇺🇸

    It has been argued that the existence of a geodesic shortcut in the Karch-Randall (KR) braneworld rules out the possibility for a low-energy intermediate theory, even when gravity is turned off. We study this problem in an explicit example with two symmetrically placed KR branes. We find that there can be a consistent quantization of bulk matter fields with a holographic intermediate description. In our model, there is no causality violation. We use this example to study potential implications of the bulk geodesic shortcut. We find that there are possible enhancements of the correlation or entanglement between the two branes that is directly correlated with the extra-dimensional geometry. This could affect the low-energy regime when there are interactions between low and high energy modes. Our model makes it clear that any possible causality violation can only arise from the UV. Independently of the quantization, an intermediate description should be valid as an EFT.

    ↳ hep-thgr-qchep-phJHEP(2026)·9 citations
27. 27*

    Lattice QCD Study of Doubly Heavy Bottom Tetraquarks

    Bhabani Sankar Tripathy🇮🇳 · Nilmani Mathur🇮🇳 · M. Padmanath🇮🇳

    Hadrons, composed of quarks and gluons bound by Quantum Chromodynamics (QCD), traditionally classified as baryons (three quarks) and mesons (quark-antiquark pairs). Nothing in the theory of QCD stands against the existence of exotic hadrons with more complex quark contents. Recent discoveries by LHCb and Belle, such as X, Y, Z states and $T_{cc}(3875)$, have renewed interest in these states. Understanding the binding mechanism within of these exotic states provides insights into QCD's non-perturbative dynamics. This work presents lattice QCD studies of two-meson interactions, involving bottom quarks, on MILC ensembles, exploring heavy tetraquark channels.

    ↳ hep-lathep-exhep-phSpringer Proc.Phys.(2026)·0 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.