Thu·Feb 6, 2025Thursday·February 6, 2025

1. 01*

   Bremsstrahlung photon contributions to parton energy loss at high virtuality ($Q^2$) : a perturbative calculation at $O({\alpha }_s{\alpha }_{em})$

   Amit Kumar🇨🇦 · Gojko Vujanovic🇨🇦

   In this work, real photon production scattering kernels from jet-medium interactions in the QCD medium are perturbatively calculated using the higher-twist (HT) formalism. Focus is given towards real photon production from a highly virtual (and highly energetic) quark, taking into account heavy-quark mass scales [Phys. Rev. C 94, 054902 (2016)], fermion-boson conversion processes [Nucl. Phys. A 793, 128 (2007)], as well as coherence effects [Phys. Rev. C 105, 024908 (2022)]. A generalized factorization procedure, such as that used in e-A deep-inelastic scattering, is employed to derive an improved single-scattering medium-induced photon emission kernels that go beyond the traditional in-medium gluon exchange approximation. Diagrams with real-photon emission from the hard quark are classified based on the final-state particles, and include two types of scattering kernels at $O({\alpha }_{em}{\alpha }_s)$ giving the following final states: (i) real photon and real quark, (ii) real photon and real gluon. The collisional kernels, thus derived, include full phase factors from all non-vanishing diagrams and complete second-order derivative terms in the transverse momentum gradient expansion. Moreover, the calculation includes heavy-quark mass effects, thus exploring heavy-quark energy loss. The in-medium parton distribution functions and the related jet transport coefficients have a hard transverse momentum dependence (of the emitted gluon or photon) present within the phase factor. It is observed that the jet transport coefficients resemble the transverse-momentum-dependent parton distribution functions.

   hep-phnucl-exnucl-thPRC(2025)·4 citations
2. 02*

   The $CP$ violations and branching ratios for $B_c^{+}\to D_{(s)}^{+}{\pi }^{+}{\pi }^{-}(K^{+}{K}^{-})$ from interference of the vector mesons in Perturbative QCD

   Kun Shuai Ye · Gang Lü · Na-Wang · Jian Chai · Xin-Heng Guo

   Within the framework of the perturbative QCD approach utilizing $K_T$ factorization, we have investigated the CP violations and branching ratios in the decay processes of $B_c^{+}\to D_{(s)}^{+}V(V\to {\pi }^{+}{\pi }^{-})$ and $B_c^{+}\to D_{(s)}^{+}V(V\to K^{+}{K}^{-})$, where V denotes three vector mesons ${\rho }^0$, $\omega$, and $\varphi$. During the $V\to {\pi }^{+}{\pi }^{-}$ and $V\to K^{+}{K}^{-}$ decay processes, we incorporated the ${\rho }^0-\omega -\varphi$ mixing mechanism to describe the amplitudes of these quasi-two-body decay processes. Within the interference regime of the three vector particles, we observed distinct changes in both CP violations and branching ratios. Furthermore, our study presents evidence for local CP violations and branching ratios that warrants further investigation through experiments.

   hep-phCPC(2025)·1 citation
3. 03*

   Novel method for determining the light quark mass ratio using ${\eta }^{\prime }\to \eta \pi \pi$ decays

   Adolfo Guevara🇲🇽 · Feng-Kun Guo🇨🇳 · Hao-Jie Jing🇨🇳

   We propose a novel approach for extracting symmetry breaking effects from symmetry conserving three-body decays. The method is based on mapping the Dalitz plot to a unit disk, and the difference of the disk distributions of two related decays isolates purely symmetry breaking effects. We demonstrate this method by extracting the fundamental parameter $Q$, an isospin breaking ratio of light quark masses defined as $Q^2\equiv (m_s^2-{\hat{m}}^2)/(m_d^2-m_u^2)$ with $\hat{m}$ the average of up and down quark masses, from the decays ${\eta }^{\prime }\to \eta {\pi }^{+}{\pi }^{-}$ and ${\eta }^{\prime }\to \eta {\pi }^0{\pi }^0$. With the Dalitz plot distributions for these two decays reported by BESIII, we illustrate the method and obtain $Q=22.5\pm 1.0$, which is consistent with previous determinations and has a comparable uncertainty. With the full BESIII data set, which is eight times larger than the one used here, a more precise determination of $Q$ should become possible. This promising and novel method can be generalized to other three-body decays to extract symmetry breaking effects.

   hep-phhep-exPRD(2026)·1 citation
4. 04*

   Improving the Direct Determination of $|V_{ts}|$ using Deep Learning

   Jeewon Heo🇰🇷 · Woojin Jang🇰🇷 · Jason Sang Hun Lee🇰🇷 · Youn Jung Roh🇰🇷 · Ian James Watson🇰🇷 · Seungjin Yang🇰🇷

   An $s$-jet tagging approach to determine the Cabibbo-Kobayashi-Maskawa matrix component $|V_{ts}|$ directly in the dileptonic final state events of the top pair production in proton-proton collisions has been previously studied by measuring the branching fraction of the decay of one of the top quarks by $t\to sW$. The main challenge is improving the discrimination performance between strange jets from top decays and other jets. This study proposes novel jet discriminators, called DISAJA, using a Transformer-based deep learning method. The first model, DISAJA-H, utilizes multi-domain inputs (jets, leptons, and missing transverse momentum). An additional model, DISAJA-L, further improves the setup by using lower-level jet constituent information, rather than the high-level clustered information. DISAJA-L is a novel model that combines low-level jet constituent analysis with event classification using multi-domain inputs. The model performance is evaluated via a CMS-like LHC Run 2 fast simulation by comparing various statistical test results to those from a Transformer-based jet classifier which considers only the individual jets. This study shows that the DISAJA models have significant performance gains over the individual jet classifier, and we show the potential of the measurement during Run 3 of the LHC and the HL-LHC.

   hep-phhep-exPRD(2025)·1 citation
5. 05*

   Extraordinary nature of the nucleon scalar charge and its densities as a signal of nontrivial vacuum structure of QCD

   Masashi Wakamatsu🇯🇵

   It is widely known that the nucleon scalar charge is proportional to the pion-nucleon sigma term as one of the important low energy observables of QCD. Especially interesting to us is the physics of the nucleon scalar charge densities. This comes from the fact that the corresponding operator has the same quantum number as the physical vacuum. It indicates unusual behavior of the the nucleon scalar density as a function of the distance $r$ from the nucleon center. Namely, it would not be reduced down to zero at the spatial infinity but rather approaches some nonzero constant corresponding to the vacuum quark condensate. Naturally, this unique nature of the nucleon scalar density in the position space also affects the corresponding density in the momentum space, i.e. the corresponding parton distribution function (PDF) as a function of the Bjorken variable $x$. This PDF is known as the chiral-odd twist-3 PDF $e(x)$. We argue that $e(x)$ is likely to have a delta-function type singularity at $x=0$, and that the appearance of this singularity can be interpreted as a signal of the nontrivial vacuum structure of the QCD.

   hep-phhep-exhep-latnucl-thSymmetry(2024)·3 citations
6. 06*

   Electronic structure of liquid xenon in the context of light dark matter direct detection

   Riccardo Catena🇸🇪 · Luca Marin🇨🇭 · Marek Matas🇨🇿 · Nicola A. Spaldin🇨🇭 · Einar Urdshals🇸🇪

   We present a description of the electronic structure of xenon within the density-functional theory formalism with the goal of accurately modeling dark-matter-induced ionisation in liquid xenon detectors. We compare the calculated electronic structures of the atomic, liquid and crystalline solid phases, and find that the electronic charge density and its derivatives in momentum space are similar in the atom and the liquid, consistent with the weak interatomic van der Waals bonding. The only notable difference is a band broadening of the highest occupied $5p$ levels, reflected in the densities of states of the condensed phases, as a result of the inter-atomic interactions. We therefore use the calculated density of states of the liquid phase, combined with the standard literature approach for the isolated atom, to recompute ionisation rates and exclusion limit curves for the XENON10 and XENON1T experiments. We find that the broadening of the 5$p$ levels induced by the liquid phase is relevant only for dark matter masses below 6 MeV, where it increases the ionisation rate relative to that of the isolated atom. For most of the explored mass range, the energies of the discrete 4$d$ and 5$s$ levels have the strongest effect on the rate. Our findings suggest a simple scheme for calculating dark matter-electron scattering rates in liquid noble gas detectors, using the calculated values for the atom weighted by the density of states of the condensed phase.

   hep-phastro-ph.COSciPost Phys.(2025)·1 citation
7. 07*

   Higgs boson precision analysis of two-Higgs-doublet models: Full LHC Run 1 and Run 2 data

   Yongtae Heo🇰🇷 · Jae Sik Lee🇰🇷 · Chan Beom Park🇰🇷

   We present the results obtained by performing global fits of two-Higgs-doublet models (2HDMs) using the full Run 1 and Run 2 Higgs datasets collected at the LHC. Avoiding unwanted tree-level flavor-changing neutral currents and including the wrong-sign cases, we consider 12 scenarios across six types of 2HDMs: Inert, type I, type II, type III, type IV, and Aligned 2HDMs. Our main results are presented in Table III and Fig. 1. We find that the type-I 2HDM provides the best fit, while the wrong-sign scenarios of the type-II and type-IV 2HDMs, where the normalized Yukawa coupling to down-type quarks is opposite in sign to the Standard Model (SM), are disfavored. We also observe that the Aligned 2HDM gives the second-best fit when the Yukawa couplings to down-type quarks take the same sign as in the SM, regardless of the sign of the Yukawa couplings to the charged leptons.

   hep-phPRD(2025)·4 citations
8. 08*

   Semihard interactions at high energies

   T. V. Iser🇧🇷 · E. G. S. Luna🇧🇷

   We revisit a minijet model to examine the behavior of the total cross section, ${\sigma }_{tot}$, and the ratio of the real to imaginary parts of the scattering amplitude, $\rho$, at high energies. In this framework, the growth of ${\sigma }_{tot}$ in $pp$ and $\bar{p}p$ channels is driven by semihard partonic processes dominated by gluon interactions. The QCD contribution to ${\sigma }_{tot}$ for the jet production is computed in the next-to-leading order. We analyze data separately from the TOTEM and ATLAS/ALFA Collaborations and find evidence in both cases suggesting the necessity of an odd semihard component that becomes asymptotically significant at high energies.

   hep-phhep-exhep-thActa Phys.Polon.Supp.(2025)·2 citations
9. 09*

   Topological Sum Rules and Spectral Flows of Chiral and Gravitational Axion-like Interactions

   Claudio Corianò🇮🇹 · Stefano Lionetti🇮🇹 · Dario Melle🇮🇹

   We examine the structure of off-shell effective actions arising from chiral and gravitational anomalies, focusing on the $JJ{J}_A$ (axial-vector/vector/vector) and $J_{A}TT$ (axial-vector/stress-energy tensors) correlators, relevant in the analysis of anomaly-driven interactions in perturbation theory. Our approach relies on conformal field theory in momentum space, extended to chiral anomalies. The analysis centers on the presence of both particle poles and anomaly poles within these interactions, characterizing their behavior both in the conformal and non conformal limits. Through explicit computations, we show that universal sum rules in the longitudinal sector regulate these interactions for all kinematic conditions, extending previous analysis, and we discuss the resulting spectral flow, an area law of the absorptive part of the anomaly form factors as one moves away from or returns to the conformal point. These features are absent in the local effective action of anomaly interactions, commonly used in the description of axion-like particles. The spectral densities in both cases are shown to be self-similar. Our results further show that anomaly poles correspond to true particle poles only in the conformal limit, when the interaction describes a massless S-matrix process supported on a null-surface. Under these conditions, they can be effectively described by two kinetically mixed pseudoscalar fields propagating on the light-cone. These studies find application in polarized deeply inelastic scattering, axion-like dark matter and analogue systems such as topological materials.

   hep-phhep-thPRD(2025)·7 citations
10. 10*

    Percolation of Domain Walls in the Two-Higgs Doublet Model

    Richard A. Battye🇬🇧 · Steven J. Cotterill🇬🇧 · Eva Sabater Andres🇬🇧 · Adam K. Thomasson🇬🇧

    Domain walls formed during a phase transition in a simple field theory model with ${\mathbb{Z}}_2$ symmetry in a periodic box have been demonstrated to annihilate as fast as causality allows and their area density scales $\propto t^{-1}$. We have performed numerical simulations of the dynamics of domain walls in the Two-Higgs Doublet Model (2HDM) where the potential has ${\mathbb{Z}}_2$ symmetry in two spatial dimensions. We observed significant differences with the standard case. Although the extreme long-time limit is the same for the $\approx 10^5$ sets of random initial configurations analysed, the percolation process is much slower due to the formation of long-lived loops. We suggest that this is due to the build up of superconducting currents on the walls which could lead ultimately to stationary configurations known as Kinky Vortons. We discuss the relevance of these findings for the production of Vortons in three spatial dimensions.

    hep-phastro-ph.COhep-thPLB(2025)·4 citations
11. 11*

    Bell Inequalities and Quantum Correlations in $H\to ZZ\to 2e2\mu$

    Mira Varma🇺🇸 · Oliver K. Baker🇺🇸

    We investigate quantum correlations in Higgs-boson decays $(H\to Z{Z}^{\ast }\to 2e2\mu )$ using CMS open data at $\sqrt{s}$ = 8 TeV, incorporating realistic detector effects. By reconstructing the polarization density matrix of the two-boson system and evaluating the Collins-Gisin-Linden-Massar-Popescu (CGLMP) Bell operator $I_3$, we quantify entanglement in the $ZZ$ state. Our analysis yields an $I_3$ value of $2.152\pm 0.003$ for signal events $(H\to Z{Z}^{\ast })$, indicating the presence of quantum entanglement. The non-resonant continuum background events $(pp\to ZZ)$ yield $I_3=1.158\pm 0.012$, suggesting the absence of quantum correlations. These results demonstrate the feasibility of testing fundamental quantum mechanics at high energy colliders.

    hep-ph2 citations
12. 12*

    ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ productions in ${\pi }^{-}p$ scattering process

    Quan-Yun Guo🇨🇳 · Dian-Yong Chen🇨🇳

    In the present work, we propose to investigate the productions of ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ in the ${\pi }^{-}p\to D^{-}{D}^{0}p$ processes by utilizing an effective Lagrangian approach, where ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ are considered as $D^{\ast }N$ molecular states with $J^P$ quantum numbers to be $1/2^{-}$ and $3/2^{-}$, respectively. With the cutoff parameter determined by the upper limit of the cross sections for ${\pi }^{-}p\to D^{\ast -}{\Lambda }_c(2286)$, the ratios of the cross sections for ${\pi }^{-}p\to D^{\ast -}{\Lambda }_c(2286)$, ${\pi }^{-}p\to D^{-}{\Lambda }_c(2286)$, ${\pi }^{-}p\to D^{-}{\Lambda }_c(2910)$, and ${\pi }^{-}p\to D^{-}{\Lambda }_c(2940)$ are estimated to be $1:4.8:1.42:0.26$ at $p_{\pi }=30$ GeV. Considering that the ${\Lambda }_c(2910)$ and ${\Lambda }_c(2940)$ state can further decay into $D^{0}p$, we estimate the cross sections for ${\pi }^{-}p\to D^{-}{D}^{0}p$ process and the differential cross sections depending on the $D^{0}p$ invariant mass spectrum. Our estimations indicate that the total cross sections are $(0.49_{-0.38}^{+1.56})$ nb when $p_{\pi }=15\mathrm{GeV}$, where the uncertainties result from the variation of the ${\Lambda }_r$. By comparing the contributions of the $s$, $u$, and $t$-channels, we conclude that the $t$-channel plays the predominant role. Moreover, the present estimations suggest that the structure around 2.9 GeV in the $D^{0}p$ invariant mass spectrum of the ${\pi }^{-}p\to D^{-}{D}^{0}p$ process should correspond to ${\Lambda }_c(2910)$ rather than ${\Lambda }_c(2940)$, which can be tested by further experimental measurements at J-PARC in the future.

    hep-phhep-exPRD(2025)·3 citations
13. 13*

    Two-loop helicity amplitudes for diphoton production with massive quark loop

    Taushif Ahmed🇩🇪 · Amlan Chakraborty🇮🇹 · Ekta Chaubey🇩🇪 · Mandeep Kaur🇮🇳

    We compute two-loop helicity amplitudes in QCD for diphoton production through quark- and gluon-initiated channels, accounting for a massive internal quark loop by keeping its full mass dependence. Using physical projectors, we directly decompose the amplitude into its helicity components. By renormalising the heavy quark mass in on-shell, and other quantities in $\overline{\mathrm{MS}}$ schemes, we obtain finite remainders. This work paves the way for calculating the cross-section for diphoton production at higher orders in QCD with a massive quark loop, employing different subtraction schemes. The effect of a heavy quark is expected to play a crucial role in high-luminosity LHC.

    hep-phhep-thJHEP(2025)·12 citations
14. 14*

    Investigating the exclusive toponium production at the LHC and FCC

    Reinaldo Francener🇧🇷 · Victor P. Goncalves🇧🇷 · Daniel E. Martins🇵🇱

    An exploratory study of the exclusive toponium production in $pp$, $pPb$ and $PbPb$ collisions at the center - of - mass energies of the Large Hadron Collider (LHC) and Future Circular Collider (FCC) is performed. Assuming that the toponium is a pseudoscalar $t\bar{t}$ state, we consider its exclusive production by photon and gluon - induced interactions. Results for the total cross - sections and associated rapidity distributions are presented, and the number of events at the LHC and FCC are estimated.

    hep-phhep-exPRD(2025)·14 citations
15. 15*

    Jet evolution in a quantum computer: quark and gluon dynamics

    Nuno Filipe Castro🇵🇹 · José Guilherme Milhano🇵🇹 · Maria Gabriela Jordão Oliveira🇵🇹

    The intrinsic quantum nature of jets and the Quark-Gluon Plasma makes the study of jet quenching a promising candidate to benefit from quantum computing power. Standing as a precursor of the full study of this phenomenon, we study the propagation of SU(3) partons in Quark-Gluon Plasma using quantum simulation algorithms. The algorithms are developed in detail, and the propagation of both quarks and gluons is analysed and compared with analytical expectations. The results, obtained with quantum simulators, demonstrate that the algorithm successfully simulates parton propagation, yielding results consistent with analytical baseline calculations.

    hep-phhep-exquant-phEPJC(2025)·6 citations
16. 16*

    Top-quark spin correlations as a tool to distinguish pseudoscalar $A\to ZH$ and scalar $H\to ZA$ signatures in $Zt\bar{t}$ final states at the LHC

    Francisco Arco🇩🇪 · Thomas Biekötter🇪🇸 · Panagiotis Stylianou🇩🇪 · Georg Weiglein🇩🇪

    Both ATLAS and CMS have recently performed the first searches for a heavy new spin-0 resonance decaying into a lighter new spin-0 resonance and a $Z$ boson, where the lighter spin-0 resonance subsequently decays into $t\bar{t}$ pairs. These searches are of particular interest to probe Two Higgs doublet model (2HDM) parameter space regions that predict a strong first-order electroweak phase transition. In the absence of CP violation, the investigated decay is possible if the lighter and the heavier spin-0 particles have opposite CP parities. The analysis techniques employed by ATLAS and CMS do not distinguish between the two possible signatures $A\to ZH$ and $H\to ZA$, where $A$ and $H$ denote CP-odd and CP-even Higgs bosons, respectively, if both signals are predicted to have the same total cross sections. We demonstrate the capability of angular variables that are sensitive to spin correlations of the top quarks to differentiate between $A\to ZH$ and $H\to ZA$ decays, even in scenarios where both signals possess identical total cross sections. Focusing on masses of 600 GeV and 800 GeV as a representative 2HDM benchmark, we find that a distinction between the two possible channels is possible with high significance with the anticipated data from the high-luminosity LHC, if the invariant mass distribution of the $t\bar{t}$ system is further binned in angular variables defined by the direction of flight of the leptons produced in the top-quark decays. Moreover, we find a moderate gain in experimental sensitivity due to the improved background rejection for both signals.

    hep-phhep-exJHEP(2025)·7 citations
17. 17*

    Flavor and CP Symmetries in the Standard Model Effective Field Theory

    Hao Sun🇨🇳 · Jiang-Hao Yu🇨🇳

    The CP properties of effective operators are closely related to the spacetime and internal symmetries, such as the flavor symmetry, in the standard model effective field theory (SMEFT). In this work, we utilize the flavor symmetry to organize and reduce numbers of independent Wilson coefficients of the SMEFT operators. We classify the dimension-6 and dimension-8 baryon/lepton-number-conserving operators based on their CP properties. The $U(1{)}^4$ rephasing symmetry is applied to distinguish CP-odd and CP-violating operators which leads to reduction of the independent CP-violating phases. The $U(3{)}^5$ and $U(2{)}^5$ flavor symmetries let us classify the CP-violating phases as the flavor invariants, which can be enumerated by the Hilbert series and obtained explicitly by the Young tensor method. Then after introducing the minimal flavor violation (MFV) hypothesis, we present the flavor structures of the dimension-6 and dimension-8 SMEFT operators under the MFV hypothesis utilizing the spurion method.

    hep-phPRD(2025)·4 citations
18. 18*

    Probing new hadronic forces with heavy exotic atoms

    Hongkai Liu🇺🇸 · Ben Ohayon🇮🇱 · Omer Shtaif🇮🇱 · Yotam Soreq🇮🇱

    We explore the potential of precision spectroscopy of heavy exotic atoms where electrons are substituted by negative hadrons to detect new force carriers with hadronic couplings. The selected transitions are unaffected by nuclear contact terms, thus enabling highly accurate calculations using bound-state QED, provided that the nuclear polarization is under control. Alternatively, we demonstrate that the dipole polarizability, a fundamental property of nuclei, can be extracted from the spectroscopy of exotic atoms in a novel way by combining two transitions while maintaining high sensitivity to new physics. Based on existing data, we extracted world-leading bounds on mediator masses ranging from $0.1$MeV to $10$MeV for two benchmark models and show that forthcoming experiments could enhance the sensitivity to new physics by two orders of magnitude.

    hep-phhep-exnucl-exphysics.atom-phPRL(2025)·15 citations
19. 19*

    Path optimization method for the sign problem caused by fermion determinant

    Kazuki Hisayoshi🇯🇵 · Kouji Kashiwa🇯🇵 · Yusuke Namekawa🇯🇵 · Hayato Takase

    The path optimization method with machine learning is applied to the one-dimensional massive lattice Thirring model, which has the sign problem caused by the fermion determinant. This study aims to investigate how the path optimization method works for the sign problem. We show that the path optimization method successfully reduces statistical errors and reproduces the analytic results. We also examine an approximation of the Jacobian calculation in the learning process and show that it gives consistent results with those without an approximation.

    ↳ hep-lathep-phPRD(2025)·4 citations
20. 20*

    Baryon-Electric Charge Correlations and Chemical Potentials as Probes of Magnetized QCD

    Heng-Tong Ding🇨🇳 · Jin-Biao Gu🇨🇳 · Arpith Kumar🇨🇳 · Sheng-Tai Li🇨🇳 · Jun-Hong Liu🇨🇳

    We present the first lattice QCD results of quadratic fluctuations and correlations of conserved charges in (2+1)-flavor lattice QCD in the presence of a background magnetic field. The simulations were performed using the Highly Improved Staggered Quarks with physical pion mass $m_{\pi }$ = 135 MeV on $N_{\tau }=8$ and 12 lattices. We find that the correlation between net baryon number and electric charge, denoted as ${\chi }_{11}^{\mathrm{BQ}}$, can serve as a magnetometer of QCD. At pseudocritical temperatures ($T_{pc}$) the ${\chi }_{11}^{\mathrm{BQ}}$ starts to increase rapidly with magnetic field strength $eB\gtrsim 2M_{\pi }^2$ and by a factor 2 at $eB\simeq 8M_{\pi }^2$. By comparing with the hadron resonance gas model, we find that the $eB$ dependence of ${\chi }_{11}^{\mathrm{BQ}}$ is mainly due to the doubly charged $\Delta$(1232) baryon. Although the doubly charged $\Delta$(1232) could not be detected experimentally, its decay products, protons and pions, retain the $eB$ dependence of $\Delta$(1232)'s contribution to ${\chi }_{11}^{\mathrm{BQ}}$. Furthermore, the ratio of electric charge chemical potential to baryon chemical potential, ${\mu }_{\mathrm{Q}}/{\mu }_{\mathrm{B}}$, shows significant dependence on the magnetic field strength and varies with the ratio of electric charge to baryon number in the colliding nuclei in heavy ion collisions. These results provide baselines for effective theory and model studies, and both ${\chi }_{11}^{\mathrm{BQ}}$ and ${\mu }_{\mathrm{Q}}/{\mu }_{\mathrm{B}}$ could be useful probes for the detection of magnetic fields in relativistic heavy ion collision experiments as compared with corresponding results from the hadron resonance gas model.

    ↳ hep-lathep-exhep-phnucl-thPoS(2025)·4 citations
21. 21*

    A confederacy of anomalies

    Jan Smit🇳🇱

    A personal recollection of early years in lattice gauge theory with a bias towards chiral symmetry and lattice fermions.

    ↳ hep-lathep-phhep-thphysics.hist-phEur.Phys.J.H(2025)·2 citations
22. 22*

    QCD Equation of State with Strong Magnetic Fields and Nonzero Baryon Density

    Heng-Tong Ding🇨🇳 · Jin-Biao Gu🇨🇳 · Arpith Kumar🇨🇳 · Sheng-Tai Li🇨🇳

    In this work, we have carried out lattice simulations of $(2+1)$-flavor QCD using highly improved staggered quarks at the physical pion mass on $32^3\times 8$ and $48^3\times 12$ lattices, with magnetic field strengths ranging up to 0.8 GeV${}^2$ and nonzero baryon chemical potentials employing the Taylor expansion framework. We present lattice QCD continuum estimate results, along with the magnetized hadron resonance and ideal gas comparisons, for the leading-order Taylor expansion coefficients for bulk thermodynamic quantities such as pressure, number density, energy density, and entropy density, focusing on the significant impact of strong magnetic fields.

    ↳ hep-lathep-phhep-thPoS(2025)·7 citations
23. 23*

    High-precision numerical evaluation of Lauricella functions

    M.A. Bezuglov🇩🇪 · B.A. Kniehl🇩🇪 · A.I. Onishchenko🇷🇺 · O.L. Veretin🇩🇪

    We present a method for high-precision numerical evaluations of Lauricella functions, whose indices are linearly dependent on some parameter $\epsilon$, in terms of their Laurent series expansions at zero. This method is based on finding analytic continuations of these functions in terms of Frobenius generalized power series. Being one-dimensional, these series are much more suited for high-precision numerical evaluations than multi-dimensional sums arising in approaches to analytic continuations based on re-expansions of hypergeometric series or Mellin--Barnes integral representations. To accelerate the calculation procedure further, the $\epsilon$ dependence of the result is reconstructed from the evaluations of given Lauricella functions at specific numerical values of $\epsilon$, which, in addition, allows for efficient parallel implementation. The method has been implemented in the $\text{PrecisionLauricella}$ package, written in Wolfram Mathematica language.

    ↳ hep-thhep-phmath-phmath.MPNPB(2025)·6 citations
24. 24*

    Finiteness of the Yang-Mills-Chern-Simons action in linear covariant gauges by taking into account gauge copies

    Daniel O. R. Azevedo🇧🇷 · Antonio D. Pereira🇧🇷

    In recent years, the effects of removing infinitesimal Gribov copies from the path integral of gauge-fixed Yang-Mills-Chern-Simons theories formulated in three-dimensional Euclidean space have been investigated. Part of the interest resides on the fact that such an elimination of gauge copies introduces a mass parameter, the Gribov parameter, which is relevant when the assumptions of the Faddeev-Popov procedure are not well-grounded. Such a parameter enters the propagator of the gauge field which is topologically massive due to the Chern-Simons term. The resulting action, which eliminates infinitesimal Gribov copies in this context, has been constructed in linear covariant gauges and the interplay between the aforementioned mass-parameters allows for a rich phase diagram in which confining and deconfining signatures are observed in the gauge-field propagator. In the present work, we establish the renormalization properties of such a theory at all orders in perturbation theory by means of the algebraic renormalization framework and show that the removal of infinitesimal Gribov copies does not affect the standard non-renormalization properties of standard gauge-fixed Yang-Mills-Chern-Simons theories, i.e., the theory is finite.

    ↳ hep-thhep-phPRD(2025)·2 citations
25. 25*

    Bounds on decaying sterile neutrinos via magnetic dipole moment from COB intensity

    Hriditi Howlader🇮🇳 · Vivekanand Mohapatra🇮🇳 · Alekha C. Nayak🇮🇳 · Tripurari Srivastava🇨🇳

    A recent observation by Long Range Reconnaissance Imager (LORRI) mounted on NASA's New Horizons yielded the most accurate measurement of the cosmic optical background (COB). The reported COB intensity is $11.16\pm 1.35$ $nW/{\mathrm{m}}^2/sr$ at a pivot wavelength ${\lambda }_{piv}=0.608\mu \mathrm{m}$ observed in the range \( 0.4 \, \mu\mathrm{m} \lesssim \lambda \lesssim 0.9 \, \mu\mathrm{m} \). After subtracting the measured intensity from the deep Hubble Space Telescope count, diffused galactic light, and scattered light from bright star foregrounds, an anomalous intensity of $2.99\pm 2.03nW/{\mathrm{m}}^2/sr$ has been found. We considered radiatively decaying sterile neutrinos of keV mass scale, as dark matter candidate, that could contribute to this anomalous reported intensity. Using this, we derive upper bounds on the sterile-to-sterile transition magnetic moment. We find that sterile neutrinos with mass of $\mathcal{O}(\mathrm{keV})$ scale take values of the transition magnetic moment in the range $3\times 10^{-13}\mathrm{e}{\mathrm{V}}^{-1}-10^{-9}\mathrm{e}{\mathrm{V}}^{-1}$ to explain the anomalous intensity of $2.99\pm 2.03nW/{\mathrm{m}}^2/sr$. % Future experiments such as, Cosmological Advanced Survey Telescope for Optical-UV Research (CASTOR), James Web Space Telescope (JWST), and Spectro-Photometer for the history of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx) might help us derive a better bound on the sterile neutrinos.

    ↳ astro-ph.COhep-phPRD(2025)·1 citation
26. 26*

    A new method for structural diagnostics with muon tomography and deep learning

    Lorenzo Pezzotti🇮🇹 · Davide Cifarelli🇮🇹 · Daniele Corradetti🇵🇹 · José Paulo Costa🇵🇹 · Giorgio Gabrielli🇮🇹 · Lorenzo Galante🇮🇹 · Antonio Gallerati🇮🇹 · Ivan Gnesi · Andrea Jouve🇮🇹 · Alessio Marrani🇮🇹

    This work investigates the production of high-resolution images of typical support elements in concrete structures by means of muon tomography (muography). By exploiting detailed Monte Carlo radiation-matter simulations, we demonstrate the feasibility of reconstructing 1 cm-thick iron bars inside 30 cm-deep concrete blocks, regarded as an important testbed within the structural diagnostics community. In addition, we present a new method for integrating simulated data with advanced deep learning techniques in order to improve the muon imaging of concrete structures. Through deep learning enhancement techniques, this results in a dramatic improvement in image quality and a significant reduction in data acquisition time, which are two critical limitations within the usual practice of muography for civil engineering diagnostics.

    ↳ hep-exhep-phphysics.comp-phphysics.geo-ph+1JINST(2025)·5 citations
27. 27*

    The SRG/eROSITA all-sky survey: Constraints on Ultra-light Axion Dark Matter through Galaxy Cluster Number Counts

    S. Zelmer🇩🇪 · E. Artis🇩🇪 · E. Bulbul🇩🇪 · S. Grandis🇦🇹 · V. Ghirardini🇮🇹 · A. von der Linden🇩🇪 · Y. E. Bahar🇩🇪 · F. Balzer🇩🇪 · M. Brüggen🇩🇪 · I. Chiu🇹🇼 · N. Clerc🇫🇷 · J. Comparat🇩🇪 and 16 other authors

    Ultralight axions are hypothetical scalar particles that influence the evolution of large-scale structures of the Universe. Depending on their mass, they can potentially be part of the dark matter component of the Universe as candidates commonly referred to as fuzzy dark matter. While strong constraints have been established for pure fuzzy dark matter models, the more general scenario where ultralight axions constitute only a fraction of the dark matter has been limited to only a few observational probes. In this work, we use the galaxy cluster number counts obtained from the first All-Sky Survey (eRASS1) of the SRG/eROSITA mission together with gravitational weak lensing data from the Dark Energy Survey, the Kilo-Degree Survey, and the Hyper Suprime-Cam to constrain the fraction of ultralight axions in the mass range $10^{-32}$ eV to $10^{-24}$ eV. We put upper bounds on the ultralight axion relic density ${\Omega }_{\mathrm{a}}$ in independent logarithmic axion mass bins by performing a full cosmological parameter inference. We find an exclusion region in the intermediate ultralight axion mass regime with the tightest bounds reported so far in the mass bins around $m_{\text{a}}=10^{-27}$ eV with ${\Omega }_{\text{a}}<0.0035$ and $m_{\text{a}}=10^{-26}$ eV with ${\Omega }_{\text{a}}<0.0079$ (95% C.L.). When combined with cosmic microwave background probes, these bounds are tightened to ${\Omega }_{\text{a}}<0.0030$ in the $m_{\text{a}}=10^{-27}$ eV mass bin and ${\Omega }_{\text{a}}<0.0058$ in the $m_{\mathrm{a}}=10^{-26}$ eV mass bin (95% C.L.). This is the first time that constraints on ultralight axions have been obtained using the growth of structure measured by galaxy cluster number counts. These results pave the way for large surveys, which can be utilized to obtain tight constraints on the mass and relic density of ultralight axions with better theoretical modeling of the abundance of halos.

    ↳ astro-ph.COhep-phAstron.Astrophys.(2025)·12 citations
28. 28*

    Gamma Ray Burst GRB 221009A: two distinct hints at once at new physics

    Giorgio Galanti🇮🇹 · Marco Roncadelli🇮🇹 · Giacomo Bonnoli🇮🇹 · Lara Nava🇮🇹 · Fabrizio Tavecchio🇮🇹

    The brightest ever observed gamma ray burst GRB 221009A at redshift $z=0.151$ was detected on October 9, 2022. Its highest energy photons have been recorded by the LHAASO collaboration up to above $12\mathrm{TeV}$, and one of the at $\mathcal{E}=251\mathrm{TeV}$ by the Carpet-2 collaboration. Very recently, the Carpet-3 collaboration has completed the data analysis, showing that the evidence of the $251\mathrm{TeV}$ photon is quite robust. Still, according to conventional physics photons with $\mathcal{E}\gtrsim 10\mathrm{TeV}$ cannot be observed owing to the absorption by the extragalactic background light (EBL). Previously it has been demonstrated that an axion-like particle (ALP) with allowed parameters ensures the observability of the LHAASO photons. Here we show that the Lorentz invariance violation allows the $\mathcal{E}=251\mathrm{TeV}$ (now around 300 TeV) Carpet photon to be detected.

    ↳ astro-ph.HEhep-ph4 citations
29. 29*

    Closing in on Pop-III Stars: Constraints and Predictions Across the Spectrum

    Omer Zvi Katz🇮🇱 · Diego Redigolo🇮🇹 · Tomer Volansky🇮🇱

    The absence of direct high redshift observations poses a significant challenge in understanding the properties of first stars. Nonetheless, the cumulative effect of entire stellar populations can be studied with current data. In this work we use a combination of high redshift observables in order to infer the formation and emission properties of the first stellar populations: high redshift UVLFs, the optical depth of CMB photons to reionization, hydrogen absorption lines in quasar spectra, and measurements of the soft cosmic X-ray background. We study two minimal models of stellar population: i) a single, Pop-II, stellar population which dominates throughout Cosmic Dawn, ii) two distinct stellar populations, Pop-II and Pop-III, dominating at different times with the transition between them taken as a free parameter. We set strong constraints on the properties of Pop-II stars, and upper limits on the formation and multi-wavelength emission of Pop-III stars. After applying the constraints above, we present the viable envelopes of the 21-cm global signal with and without Pop-III stars. We identify a region in the parameter space of the two population model which predicts a global 21-cm signal distinctive from that of the single population one. A measurement of such a signal would be a strong indication for the presence of Pop-III stars at early times.

    ↳ astro-ph.COastro-ph.GAhep-phJCAP(2025)·10 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.