Mon·May 13, 2024Monday·May 13, 2024

1. 01*

   Hunting a charged Higgs boson pair in proton-proton collisions

   M. A. Arroyo-Ureña🇲🇽 · E. A. Herrera-Chacón🇬🇧 · S. Rosado-Navarro🇻🇪 · Humberto Salazar🇲🇽

   We explore the production and possible detection of a charged scalar Higgs pair $H^{-}{H}^{+}$ decaying into the final state $\mu {\nu }_{\mu }cb$ in proton-proton collisions at the LHC and its next step, the High Luminosity LHC (HL-LHC). The charged scalars are predicted within the theoretical framework of the Two-Higgs Doublet Model of type III (2HDM-III). As a test and validation of the model, we identify regions of the 2HDM-III parameter space that accommodate the current excess of events at $3\sigma$ in the process $\mathcal{B}\mathcal{R}(t\to H^{\pm }b)\times \mathcal{B}\mathcal{R}(H^{\pm }\to cb)$ for $M_{H^{\pm }}=130$ GeV, as reported by the ATLAS collaboration. Theoretical and additional experimental constraints are also included. Based on this, we propose realistic scenarios that could be brought under experimental scrutiny at the HL-LHC. Assuming the most favorable scenario, we predict a signal significance at the level of $5\sigma$ for a charged scalar boson mass $M_{H^{\pm }}$ in the $100-350$ GeV range.

   hep-phPRD(2025)·12 citations
2. 02*

   Searches for the BSM scenarios at the LHC using decision tree based machine learning algorithms: A comparative study and review of Random Forest, Adaboost, XGboost and LightGBM frameworks

   Arghya Choudhury🇮🇳 · Arpita Mondal🇮🇳 · Subhadeep Sarkar🇮🇳

   Machine learning algorithms are now being extensively used in our daily lives, spanning across diverse industries as well as academia. In the field of high energy physics (HEP), the most common and challenging task is separating a rare signal from a much larger background. The boosted decision tree (BDT) algorithm has been a cornerstone of the high energy physics for analyzing event triggering, particle identification, jet tagging, object reconstruction, event classification, and other related tasks for quite some time. This article presents a comprehensive overview of research conducted by both HEP experimental and phenomenological groups that utilize decision tree algorithms in the context of the Standard Model and Supersymmetry (SUSY). We also summarize the basic concept of machine learning and decision tree algorithm along with the working principle of \texttt{Random Forest}, \texttt{AdaBoost} and two gradient boosting frameworks, such as \texttt{XGBoost}, and \texttt{LightGBM}. Using a case study of electroweakino productions at the high luminosity LHC, we demonstrate how these algorithms lead to improvement in the search sensitivity compared to traditional cut-based methods in both compressed and non-compressed R-parity conserving SUSY scenarios. The effect of different hyperparameters and their optimization, feature importance study using SHapley values are also discussed in detail.

   hep-phhep-exphysics.comp-phEur.Phys.J.ST(2024)·24 citations
3. 03*

   First Radial Excitations of Mesons and Diquarks in a Contact Interaction

   G. Paredes-Torres🇲🇽 · L.X. Gutiérrez-Guerrero🇲🇽 · A. Bashir🇲🇽 · Ángel S. Miramontes🇲🇽

   We present a calculation for the masses of the first radially excited states of forty mesons and diquarks made up of $u,d,s,c$ and $b$ quarks, including states that contain one or both heavy quarks. To this end, we employ a combined analysis of the Bethe-Salpeter and Schwinger-Dyson equations within a self-consistent and symmetry preserving vector-vector contact interaction. The same set of parameters describe ground and excited states of mesons and their diquark partners. The wave-function of the first radial excitation contains a zero whose location is correlated with an additional parameter $d_F$ which is a function of dressed quark masses. Our results satisfy the equal spacing rules given by the Gell-Mann Okubo mass relations. Wherever possible, we make comparisons of our findings with known experimental observations as well as theoretical predictions of several other models and approaches including lattice quantum chromodynamics, finding a very good agreement. We report predictions for a multitude of radial excitations not yet observed in experiments.

   hep-phnucl-thPRD(2024)·14 citations
4. 04*

   Thermal Dark Photon Dark Matter, Coscattering, and Long-lived ALPs

   Bastián Díaz Sáez🇨🇱

   We study the thermal freeze-out of a dark photon dark matter in the so-called dark-axion portal - a triple coupling among a dark photon, an axion-like particle and the SM $\gamma$ or $Z$ boson. We analyze in detail the thermal production regimes: coscattering (aka conversion driven freeze-out), mediator freeze-out, and coannihilations. We found viable DM scenarios fulfilling the correct relic abundance in the three regimes. Apart of analyzing the parameter space for dark state masses between the GeV-TeV scale, we explore the prospects of having the axion-like field as a long-lived particle, possibly to be observed at the LHC and future detectors.

   hep-phPhys.Dark Univ.(2025)·10 citations
5. 05*

   Leptophilic Portals to New Physics at Colliders

   P. S. Bhupal Dev🇺🇸

   Observed neutrino oscillations imply that the global lepton flavor symmetry of the Standard Model must be broken. Therefore, searches for lepton flavor violation (LFV) are promising probes of new physics beyond the Standard Model. High-energy colliders provide a powerful tool to study LFV effects, which are complementary to the low-energy charged LFV searches. Here we discuss the possibility of LFV signals at colliders arising from exotic Higgs decays, and from leptophilic scalar and vector portal scenarios.

   hep-phhep-exSciPost Phys.Proc.(2025)·0 citations
6. 06*

   Flavor dependent Critical endpoint from holographic QCD through machine learning

   Xun Chen🇨🇳 · Mei Huang🇨🇳

   QCD phase diagram in the $T-\mu$ plane and the equation of state for pure gluon, 2-flavor, 2+1-flavor systems, and 2+1+1-flavor systems have been investigated using the Einstein-Maxwell-Dilaton (EMD) framework at finite temperature and chemical potential. By inputting lattice QCD data for the equation of state and baryon number susceptibility at zero chemical potential into holographic model, all the parameters can be determined with the aid of machine learning algorithms. Our findings indicate that the deconfinement phase transition is of first order for the pure gluon system with critical temperature $T_c=0.265$ GeV at vanishing chemical potential. The phase transition for the 2-flavor, 2+1-flavor systems, and 2+1+1-flavor systems are crossover at vanishing chemical potential and first-order at high chemical potential, and the critical endpoint (CEP) in the $T-\mu$ plane locates at (${\mu }_B^c$=0.46 GeV, $T^c$=0.147 GeV), (${\mu }_B^c$ = 0.74 GeV, $T^c$ = 0.094 GeV), and (${\mu }_B^c$= 0.87 GeV,$T^c$ = 0.108 GeV), respectively. Additionally, the thermodynamic quantities of the system for different flavors at finite chemical potential are presented in this paper. It is observed that the difference between the 2+1-flavor and 2+1+1-flavor systems is invisible at vanishing chemical potential and low temperature. The location of CEP for 2+1+1-flavor system deviates explicitly from that of the 2+1-flavor system with the increase of chemical potential. Both 2+1-flavor and 2+1+1-flavor systems differ significantly from the 2-flavor system. Moreover, at zero temperature, the critical chemical potential is found to be ${\mu }_B$ = 1.1 GeV, 1.6 GeV, 1.9 GeV for the 2-flavor, 2+1-flavor and 2+1+1-flavor systems, respectively.

   hep-phJHEP(2025)·42 citations
7. 07*

   Minimal Dark Matter Freeze-in with Low Reheating Temperatures and Implications for Direct Detection

   Kimberly K. Boddy🇺🇸 · Katherine Freese🇺🇸 · Gabriele Montefalcone🇺🇸 · Barmak Shams Es Haghi🇺🇸

   We investigate the influence of the reheating temperature of the visible sector on the freeze-in dark matter (DM) benchmark model for direct detection experiments, where DM production is mediated by an ultralight dark photon. Here we consider a new regime for this benchmark: we take the initial temperature of the thermal Standard Model (SM) bath to be below the DM mass. The production rate from the SM bath is drastically reduced due to Boltzmann suppression, necessitating a significant increase in the portal coupling between DM and the SM to match the observed relic DM abundance. This enhancement in coupling strength increases the predicted DM-electron scattering cross section, making freeze-in DM more accessible to current direct detection experiments.

   hep-phastro-ph.COhep-exPRD(2025)·45 citations
8. 08*

   Anatomy of critical fluctuations in hadronic matter

   Michał Marczenko🇵🇱

   Critical phenomena in phase transitions of strongly interacting matter, governed by quantum chromodynamics, are inherently encoded in the fluctuations of conserved charges. In this work, we study the net-baryon number density fluctuations, including the lowest-lying nucleon and the baryonic resonance $\Delta (1232)$, based on the parity doublet model in the mean-field approximation. We focus on the qualitative features of the second-order susceptibility of the net-baryon number density in dense hadronic matter and how the inclusion of $\Delta (1232)$ affects it. We demonstrate that the fluctuations of the individual baryons do not necessarily reflect the total net-baryon number fluctuations at finite density, due to the non-trivial correlations between different particle species. Our results highlight the role of baryonic correlations in the interpretation of data from heavy ion collision experiments.

   hep-phnucl-thPRD(2024)·8 citations
9. 09*

   Probing superheavy dark matter through lunar radio observations of ultrahigh-energy neutrinos and the impacts of neutrino cascades

   Saikat Das🇯🇵 · Jose Alonso Carpio🇺🇸 · Kohta Murase🇺🇸

   Ultrahigh-energy neutrinos (UHE$\nu$s) can be used as a valuable probe of superheavy dark matter above $\sim 10^9$ GeV, the latter being difficult to probe with collider and direct detection experiments due to the feebly interacting nature. Searching for radio emissions originating from the interaction of UHE$\nu$s with the lunar regolith enables us to explore energies beyond $10^{12}$ GeV, which astrophysical accelerators cannot achieve. Taking into account the interaction of UHE$\nu$s with the cosmic neutrino background and resulting standard neutrino cascades to calculate the neutrino flux on Earth, for the first time, we investigate sensitivities of such lunar radio observations to very heavy dark matter. We also examine the impacts of cosmogenic neutrinos that have the astrophysical origin. We show that the proposed ultra-long wavelength lunar radio telescope, as well as the existing low-frequency array, can provide the most stringent constraints on decaying or annihilating superheavy dark matter with masses at $\gtrsim 10^{12}$ GeV. The limits are complementary to or even stronger than those from other UHE$\nu$ detectors, such as the IceCube-Gen2 radio array and GRAND.

   hep-phastro-ph.HEPRD(2025)·21 citations
10. 10*

    Deconfinement and chiral restoration phase transition under rotation from holography in an anisotropic gravitational background

    Yidian Chen🇨🇳 · Xun Chen🇨🇳 · Danning Li🇨🇳 · Mei Huang🇨🇳

    We investigate the effects of rotation on deconfinement and chiral phase transitions in the framework of dynamical holographic QCD model. Instead of transforming to the rotating system by Lorentz boost, we construct an anisotropic gravitational background by incorporating the rotating boundary current. We firstly investigate the pure gluon system under rotation to extract deconfinement phase transition from the Polyakov loop then add 2-flavor probe for chiral restoration phase transition from the chiral condensate. It is observed that at low chemical potentials, the deconfinement phase transition of pure gluon system is of first order and the chiral phase transition of 2-flavor system is of crossover. Both the critical temperatures of deconfinement and chiral phase transitions decrease/increase with imaginary/real angular velocity (${\Omega }_I/\Omega$) as $T/T_c\sim 1-C_2{\Omega }_I^2$ and $T/T_c\sim 1+C_2{\Omega }^2$, which is consistent with lattice QCD results. In the temperature-chemical potential $T-\mu$ phase diagram, the critical end point (CEP) moves towards regions of higher temperature and chemical potential with real angular velocity.

    hep-phPRD(2025)·35 citations
11. 11*

    Hadron Spectroscopy: Light, Strange Baryons

    Chandni Menapara🇮🇳 · Ajay Kumar Rai🇮🇳

    The resonance mass spectra have been studied through a non-relativistic hypercentral Constituent Quark Model (hCQM) using a linear potential. Also, the effects of higher order correction terms ($\mathcal{O}(\frac{1}{m})$, $\mathcal{O}(\frac{1}{m^2})$) have been studied for improvisation of the results. Other baryonic properties such as Regge trajectories, magnetic moment and decay widths have been considered. A detailed comparison with other approaches are discussed in the present review.

    hep-phFew Body Syst.(2024)·8 citations
12. 12*

    Soft quark effects on H+jet production at NLP accuracy

    Sourav Pal🇮🇳 · Satyajit Seth🇮🇳

    We define soft quark operators that enable construction of colour-ordered helicity amplitudes out of the non-radiative ones. We explore these operators for Higgs plus one jet production in a hadron collider and study the next-to-leading power corrections on all partonic channels involving quark(s) and/or anti-quark(s). We also investigate the effect of next-to-soft gluon radiation in these channels employing the technique illustrated in \cite{Pal:2023vec}. Analytical expressions of next-to-leading power leading logarithms thus obtained are simple and compact in nature. Further, we discuss the connection of such logarithms with that of the pseudo-scalar Higgs plus one jet production.

    hep-phPLB(2025)·9 citations
13. 13*

    Modular Invariant Slow Roll Inflation

    Gui-Jun Ding🇨🇳 · Si-Yi Jiang🇨🇳 · Wenbin Zhao🇩🇪

    We propose new classes of inflation models based on the modular symmetry, where the modulus field $\tau$ serves as the inflaton. We establish a connection between modular inflation and modular stabilization, wherein the modulus field rolls towards a fixed point along the boundary of the fundamental domain. We find the modular symmetry strongly constrain the possible shape of the potential and identify some parameter space where the inflation predictions agree with cosmic microwave background observations. The tensor-to-scalar ratio is predicted to be smaller than $10^{-6}$ in our models, while the running of spectral index is of the order of $10^{-4}$.

    hep-phastro-ph.COhep-thJCAP(2024)·32 citations
14. 14*

    Constraints on primordial lepton asymmetries with full neutrino transport

    Julien Froustey🇺🇸 · Cyril Pitrou🇫🇷

    Primordial neutrino-antineutrino asymmetries can be constrained through big-bang nucleosynthesis (BBN) relic abundances and cosmic microwave background (CMB) anisotropies, both observables being sensitive to neutrino properties. The latter constraint, which is due to gravitational effects from all neutrino flavors, is very minute since it is at least quadratic in the asymmetries. On the contrary, the constraints from primordial abundances presently dominate, although these abundances are almost only sensitive to the electron flavor asymmetry. It is generally assumed that neutrino asymmetries are sufficiently averaged by flavor oscillations prior to BBN, which allows one to constrain a common primordial neutrino asymmetry at the epoch of BBN. This simplified approach suffers two caveats that we deal with in this article, combining a neutrino evolution code and BBN calculation throughout the MeV era. First, flavor "equilibration" is not true in general, therefore an accurate dynamical evolution of asymmetries is needed to connect experimental observables to the primordial asymmetries. Second, the approximate averaging of asymmetries through flavor oscillations is associated to a reheating of the primordial plasma. It is therefore crucial to correctly describe the interplay between flavor equilibration and neutrino decoupling, as an energy redistribution prior to decoupling does not significantly alter the final effective number of neutrino species' value. Overall, we find that the space of allowed initial asymmetries is generically unbound when using currently available primordial abundances and CMB measurements. We forecast constraints using future CMB experiment capabilities, which should reverse this experimental misfortune.

    hep-phastro-ph.COPRD(2024)·38 citations
15. 15*

    Algorithms for partial wave amplitudes under covariant $L$-$S$ scheme

    Hao-Jie Jing🇨🇳 · Shu-Ming Wu🇨🇳 · Jia-Jun Wu🇨🇳

    With the continuous accumulation of data from hadron collision experiments, efficient Partial Wave Analysis tools are indispensable for constructing a clear hadron spectrum. Currently, automated computations of scattering amplitudes primarily use the helicity scheme and covariant effective Lagrangian method. The automated calculations under the covariant $L$-$S$ scheme, which is one of the commonly used partial wave analysis schemes, have not been fully realized. In this work, we provide a general algorithm for computing partial wave amplitudes under the covariant $L$-$S$ scheme. This will lay the foundation for automated computation of partial wave amplitudes under the covariant $L$-$S$ scheme.

    hep-phhep-exPRD(2024)·3 citations
16. 16*

    Inflationary Gravitational Wave Spectral Shapes as test for Low-Scale Leptogenesis

    Zafri A. Borboruah🇮🇳 · Anish Ghoshal🇵🇱 · Lekhika Malhotra🇮🇳 · Urjit Yajnik🇮🇳

    We study non-thermal resonant leptogenesis in a general setting where a heavy majoron $\varphi$ decays to right-handed neutrinos (RHNs) whose further out-of-equilibrium decay generates the required lepton asymmetry. Domination of the energy budget of the Universe by the $\varphi$ or the RHNs alters the evolution history of the primordial gravitational waves (PGW) of inflationary origin, which re-enter the horizon after inflation, modifying the spectral shape. The decays of $\varphi$ and RHNs release entropy into the early Universe while nearly degenerate RHNs facilitate low and intermediate-scale leptogenesis. A characteristic damping of the GW spectrum resulting in knee-like features would provide evidence for low-scale non-thermal leptogenesis. We explore the parameter space for the lightest right-handed neutrino mass $M_1\in [10^2,10^{14}]$ GeV and washout parameter $K$ that depends on the light-heavy neutrino Yukawa couplings $\lambda$, in the weak ($K<1$) and strong ($K>1$) washout regimes. The resulting novel features compatible with observed baryon asymmetry are detectable by future experiments like LISA and ET. By estimating signal-to-noise ratio (SNR) for upcoming GW experiments, we investigate the effect of the majoron mass $M_{\varphi }$ and reheating temperature $T_{\varphi }$, which depends on the $\varphi -N$ Yukawa couplings $y_N$.

    hep-phastro-ph.COgr-qchep-thPRD(2025)·10 citations
17. 17*

    One-photon annihilation of the electron-positron pair at heavy atomic nuclei

    Alexei M. Frolov🇨🇦

    We investigate one-photon annihilation of the electron-positron pair in the field of a central, very heavy and positively charged atomic nucleus. The explicit formula for the annihilation rate of this process ${\Gamma }_{1\gamma }^{(b)}$ is derived. Our formula for this rate can directly be used to describe the actual one-photon annihilation in the ground (bound) states of all positronium hydrides HPs, quasi-stable triplet states of the positron-helium atoms $e^{+}[$ He($2^3{S}_e$)] ions and other systems.

    hep-phnucl-thquant-phPLA(2025)·0 citations
18. 18*

    Model-independent Odderon results based on new TOTEM data on elastic pp collisions at 8 TeV

    T. Csörgő🇭🇺 · T. Novák🇭🇺 · R. Pasechnik🇸🇪 · A. Ster🇭🇺 · I. Szanyi🇭🇺

    Evaluating the H(x, s; pp) scaling function of elastic proton-proton (pp) collisions from recent TOTEM data at sqrt(s) = 8 TeV and comparing it with the same function of elastic proton-antiproton (pp-) data of the D0 collaboration at sqrt(s) = 1.96 TeV, we find, from this comparison alone, an at least 3.79 sigma {\signal} of Odderon exchange. If we combine this model independently obtained result with that of a similar analysis but using TOTEM elastic pp scattering data at sqrt(s) = 7 TeV, which resulted in an at least 6.26 {\sigma} signal, the combined significance of Odderon exchange increases to at least 7.08 {\sigma}, model independently. Further combinations of various datasets in the TeV energy range are detailed in the manuscript

    hep-phhep-exUniverse(2024)·4 citations
19. 19*

    Primordial Gravitational Waves as Probe of Dark Matter in Interferometer Missions: Fisher Forecast and MCMC

    Anish Ghoshal🇵🇱 · Debarun Paul🇮🇳 · Supratik Pal🇮🇳

    We propose novel inflationary primordial gravitational wave (GW) spectral shapes at interferometer-based current and future GW missions to test dark matter (DM) production via gravity-portal.We consider three right-handed neutrinos (RHNs), the lightest among them is DM candidate while the others participate in baryogenesis via leptogenesis. We find that future GW detectors BBO, DECIGO, ET, for instance, are able to probe DM mass for $5\times 10^6\mathrm{GeV}<M_{\mathrm{DM}}<1.6\times 10^7$ GeV with a signal-to-noise ratio (SNR) $>10$, along with the observed amount of baryon asymmetry due to gravitational leptogenesis for heavy RHN mass $M_{\mathcal{N}}$ to be around $8\times 10^{12}$ GeV. Employing Fisher matrix forecast analysis, we identify the parameter space involving non-minimal coupling to gravity $\xi$, reheating temperature of the Universe $T_{\mathrm{rh}}$ and DM mass $M_{\mathrm{DM}}$ where the GW detector-sensitivities will be the maximum with the least error, along with SNR $>10$. Finally, utilizing mock data for each GW detector, we perform MCMC analysis to find out the combined constraints on the various microphysics parameters. We also explore production of other cosmological relics such as QCD axion relic as DM candidate, produced via gravity-portal in early universe. We find that ET, for instance, can probe the decay constant of such DM candidates ($f_a$) as $10^9\mathrm{GeV}\lesssim f_a\lesssim 10^{14}\mathrm{GeV}$ for misalignment angle ${\theta }_i\in [0.1,\pi /\sqrt{3}]$ and $\xi =1$ with SNR $>10$, whereas this range decreases with the increase of non-minimal coupling. Thus the upcoming GW missions will be able to test such non-thermal DM and baryogenesis scenarios involving very high energy scales, which is otherwise impossible to reach in particle physics experiments in laboratories.

    hep-phastro-ph.COgr-qchep-thJHEP(2024)·17 citations
20. 20*

    Disentangling new physics in $K\to \pi \bar{\nu }\nu$ and $B\to K(K^{\ast })\bar{\nu }\nu$ observables

    Andrzej J. Buras🇩🇪 · Julia Harz🇩🇪 · Martin A. Mojahed🇩🇪

    We investigate the possibility of disentangling different new physics contributions to the rare meson decays $K\to \pi +/E$ and $B\to K(K^{\ast })+/E$ through kinematic distributions in the missing energy $/E$. We employ dimension-$6$ operators within the Low-Energy Effective Field Theory (LEFT), identifying the invisible part of the final state as either active or sterile neutrinos. Special emphasis is given to lepton-number violating (LNV) operators with scalar and tensor currents. We show analytically that contributions from scalar, vector, and tensor quark currents can be uniquely determined from experimental data of kinematic distributions. In addition, we present new correlations of branching ratios for $K$ and $B$-decays involving scalar and tensor currents. As there could a priori also be new invisible particles in the final states, we include dark-sector operators giving rise to two dark scalars, fermions, or vectors in the final state. In this context, we present new calculations of the inclusive decay rate $B\to X_s+/E$ for dark operators. We show that careful measurements of kinematic distributions make it theoretically possible to disentangle the contribution from LEFT operators from most of the dark-sector operators, even when multiple operators are contributing. We revisit sum rules for vector currents in LEFT and show that the latter are also satisfied in some new dark-physics scenarios that could mimic LEFT. Finally, we point out that an excess in rare meson decays consistent with a LNV hypothesis would point towards highly flavor non-democratic physics in the UV, and could put high-scale leptogenesis under tension.

    hep-phhep-exhep-latJHEP(2024)·65 citations
21. 21*

    Transforming the Bootstrap: Using Transformers to Compute Scattering Amplitudes in Planar N = 4 Super Yang-Mills Theory

    Tianji Cai🇺🇸 · Garrett W. Merz🇺🇸 · François Charton🇫🇷 · Niklas Nolte🇫🇷 · Matthias Wilhelm🇩🇰 · Kyle Cranmer🇺🇸 · Lance J. Dixon🇺🇸

    We pursue the use of deep learning methods to improve state-of-the-art computations in theoretical high-energy physics. Planar N = 4 Super Yang-Mills theory is a close cousin to the theory that describes Higgs boson production at the Large Hadron Collider; its scattering amplitudes are large mathematical expressions containing integer coefficients. In this paper, we apply Transformers to predict these coefficients. The problem can be formulated in a language-like representation amenable to standard cross-entropy training objectives. We design two related experiments and show that the model achieves high accuracy (> 98%) on both tasks. Our work shows that Transformers can be applied successfully to problems in theoretical physics that require exact solutions.

    ↳ cs.LGcs.SChep-phhep-th+1Mach.Learn.Sci.Tech.(2024)·31 citations
22. 22*

    New comprehensive description of the scaling evolution of the cosmological magneto-hydrodynamic system

    Fumio Uchida🇯🇵 · Motoko Fujiwara🇩🇪 · Kohei Kamada🇯🇵 · Jun'ichi Yokoyama🇯🇵

    We study the evolution of primordial magnetic fields until the recombination epoch, which is constrained by the conservation of magnetic helicity density if they are maximally helical and by the Hosking integral if they are non-helical. We combine these constraints with conditions obtained by estimating time scales of energy dissipation processes to describe the evolution of magnetic field strength and magnetic coherence length analytically. The dissipation processes depend on whether magnetic or kinetic energy is dominant, whether the decay dynamics is linear or not, and whether the dominant dissipation term is shear viscosity or drag force. We apply the description to compare constraints on primordial magnetic fields at different epochs in the early universe and argue that magnetogenesis before the electroweak symmetry breaking is not feasible.

    ↳ astro-ph.COhep-phphysics.flu-dynJCAP(2025)·9 citations
23. 23*

    Reconstructing generalised parton distributions from the lattice off-forward Compton amplitude

    A. Hannaford-Gunn🇦🇺 · K. U. Can🇦🇺 · J. A. Crawford🇦🇺 · R. Horsley🇬🇧 · P. E. L. Rakow🇬🇧 · G. Schierholz🇩🇪 · H. Stüben🇩🇪 · R. D. Young🇦🇺 · J. M. Zanotti🇦🇺

    We present a determination of the structure functions of the off-forward Compton amplitude ${\mathcal{H}}_1$ and ${\mathcal{E}}_1$ from the Feynman-Hellmann method in lattice QCD. At leading twist, these structure functions give access to the generalised parton distributions (GPDs) $H$ and $E$, respectively. This calculation is performed for an unphysical pion mass of $m_{\pi }=412\text{MeV}$ and four values of the soft momentum transfer, $t\approx 0,-0.3,-0.6,-1.1{\text{GeV}}^2$, all at a hard momentum scale of ${\bar{Q}}^2\approx 5{\text{GeV}}^2$. Using these results, we test various methods to determine properties of the real-time scattering amplitudes and GPDs: (1) we fit their Mellin moments, and (2) we use a simple GPD ansatz to reconstruct the entire distribution. Our final results show promising agreement with phenomenology and other lattice results, and highlight specific systematics in need of control.

    ↳ hep-lathep-phnucl-thPRD(2024)·22 citations
24. 24*

    Statistical divergences in high-dimensional hypothesis testing and a modern technique for estimating them

    Jeremy J.H. Wilkinson · Christopher G. Lester🇬🇧

    Hypothesis testing in high dimensional data is a notoriously difficult problem without direct access to competing models' likelihood functions. This paper argues that statistical divergences can be used to quantify the difference between the population distributions of observed data and competing models, justifying their use as the basis of a hypothesis test. We go on to point out how modern techniques for functional optimization let us estimate many divergences, without the need for population likelihood functions, using samples from two distributions alone. We use a physics-based example to show how the proposed two-sample test can be implemented in practice, and discuss the necessary steps required to mature the ideas presented into an experimental framework. The code used has been made available for others to use.

    ↳ physics.data-anhep-exhep-phmath.ST+10 citations
25. 25*

    Renormalization Flow of Nonlinear Electrodynamics

    Holger Gies🇩🇪 · Julian Schirrmeister🇩🇪

    We study the renormalization flow of generic actions that depend on the invariants of the field strength tensor of an abelian gauge field. While the Maxwell action defines a Gaussian fixed point, we search for further non-Gaussian fixed points or rather fixed functions, i.e., globally existing Lagrangians of the invariants. Using standard small-field expansion techniques for the resulting functional flow equation, a large number of fixed points is obtained, which - in analogy to recent findings for a shift-symmetric scalar field - we consider as approximation artifacts. For the construction of a globally existing fixed function, we pay attention to the use of proper initial conditions. Parametrizing the latter by the photon anomalous dimension, both the coefficients of the weak-field expansion are fully determined and those of the large-field expansion can be matched such that a global fixed function can be constructed for magnetic fields. The anomalous dimension also governs the strong-field limit. Our results provide evidence for the existence of a continuum of non-Gaussian fixed points parametrized by a small positive anomalous dimension below a critical value. We discuss the implications of this result within various scenarios with and without additional matter. For the strong-field limit of the 1PI QED effective action, where the anomalous dimension is determined by electronic fluctuations, our result suggests the existence of a singularity free strong-field limit, circumventing the standard conclusions connected to the perturbative Landau pole.

    ↳ hep-thhep-phPRD(2024)·2 citations
26. 26*

    Scattering of dark pions in Sp(4) gauge theory

    Yannick Dengler🇦🇹 · Axel Maas🇦🇹 · Fabian Zierler🇬🇧

    Analyzes of astrophysical data provide first hints on the self-interactions of dark matter at low energies. Lattice calculations of dark matter theories can be used to investigate them, especially in the case of strongly-interacting dark matter. We consider Sp(4) gauge theory with two fundamental fermions as a candidate theory. We compute the scattering phase shift for the scattering of two identical dark pions and determine the parameters of the effective range expansion. Our exploratory results in the supposedly most common interaction channel provide a lower limit for the dark matter mass when compared to astrophysical data. We also provide first benchmarks of velocity-weighted cross-sections in the relevant non-relativistic domain.

    ↳ hep-latastro-ph.GAhep-phPRD(2024)·28 citations
27. 27*

    Steady electric currents in magnetized QCD and their use for the equation of state

    B. B. Brandt🇩🇪 · G. Endrődi🇩🇪 · G. Markó🇩🇪 · A. D. M. Valois🇩🇪

    In this paper we study the emergence of steady electric currents in QCD as a response to a non-uniform magnetic background using lattice simulations with 2 + 1 quark flavors at the physical point, as well as leading-order chiral perturbation theory. Using these currents, we develop a novel method to determine the leading-order coefficient of the equation of state in a magnetic field expansion: the magnetic susceptibility of the QCD medium. We decompose the current expectation value into valence- and sea-quark contributions and demonstrate that the dominant contribution to the electric current is captured by the valence term alone, allowing for a comparably cheap determination of the susceptibility. Our continuum extrapolated lattice results for the equation of state confirm the findings of some of the existing studies in the literature, namely that the QCD medium behaves diamagnetically at low and paramagnetically at high temperatures.

    ↳ hep-lathep-exhep-phhep-th+1JHEP(2024)·8 citations
28. 28*

    Calo-VQ: Vector-Quantized Two-Stage Generative Model in Calorimeter Simulation

    Qibin Liu🇨🇳 · Chase Shimmin🇺🇸 · Xiulong Liu🇺🇸 · Eli Shlizerman🇨🇳 · Shu Li🇨🇳 · Shih-Chieh Hsu🇺🇸

    We introduce a novel machine learning method developed for the fast simulation of calorimeter detector response, adapting vector-quantized variational autoencoder (VQ-VAE). Our model adopts a two-stage generation strategy: initially compressing geometry-aware calorimeter data into a discrete latent space, followed by the application of a sequence model to learn and generate the latent tokens. Extensive experimentation on the Calo-challenge dataset underscores the efficiency of our approach, showcasing a remarkable improvement in the generation speed compared with conventional method by a factor of 2000. Remarkably, our model achieves the generation of calorimeter showers within milliseconds. Furthermore, comprehensive quantitative evaluations across various metrics are performed to validate physics performance of generation.

    ↳ physics.ins-detcs.LGhep-ph28 citations
29. 29*

    Steps Toward Quantum Simulations of Hadronization and Energy-Loss in Dense Matter

    Roland C. Farrell🇺🇸 · Marc Illa🇺🇸 · Martin J. Savage🇺🇸

    A framework for simulating the real-time dynamics of composite particles in a simple model of dense matter that is amenable to quantum computers is developed. As a demonstration, we perform classical simulations of heavy-hadrons propagating through a dense medium in the Schwinger model. Measurements of the time-dependent energy and charge density are used to identify mechanisms responsible for energy loss and hadron production (hadronization). A study of entanglement dynamics highlights the importance of quantum coherence between the particles that make up the dense medium. Throughout this work, care is taken to isolate, and remove, phenomena that arise solely from a finite lattice spacing. It is found that signatures of entanglement are more sensitive to lattice artifacts than other observables. Toward quantum simulations, we present an efficient method and the corresponding quantum circuits for preparing ground states in the presence of heavy mesons. These circuits are used to estimate the resources required to simulate in-medium energy loss and hadronization in the Schwinger model using quantum computers.

    ↳ quant-phhep-lathep-phnucl-thPRC(2025)·37 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.