Wed·Sep 10, 2025Wednesday·September 10, 2025

1. 01*

   Indirect detection of boosted light scalar dark matter

   Arindam Basu🇮🇳

   We explore the possibilities of detecting MeV-scale boosted dark matter (DM) via astrophysical observations. Given a particular model framework, using gamma-ray data from \texttt{COMPTEL} and \texttt{EGRET}, as well as neutrino constraints from the \texttt{Super-Kamiokande}, \texttt{Hyper-Kamiokande}, \texttt{JUNO}, diffuse supernova neutrino background (\texttt{DSNB}), and atmospheric neutrino observations, we find that boosted light scalar DM could be probed within the mass range of $\sim 20-80$ MeV, satisfying the Planck observed relic abundance. Our study shows, indirect search can play a key role in the detection of MeV-scale boosted DM, which are otherwise beyond the reach of usual collider or DM scattering experiments.

   hep-phhep-th0 citations
2. 02*

   Isospin symmetry breaking and gluon anomaly

   A.A. Osipov🇷🇺

   The contribution of the electromagnetic interaction to the self-energy of pseudo-Goldstone bosons, as well as to the mixing angles and weak decay constants, is calculated in the first nonleading order in the simultaneous expansion in powers of $1/N_c$, momenta and quark masses. Particular attention is paid to the isospin symmetry breaking which is generated by means of $\eta$ and ${\eta }^{\prime }$ admixtures to the pion. It is shown that the gluon anomaly enhances the electromagnetic contribution to the ${\pi }^0$-$\eta$ and ${\pi }^0$-${\eta }^{\prime }$ mixing angles, which facilitates the restoration of isospin symmetry in the spectrum of pseudo-Goldstone states at next-to-leading order. The contribution of the electromagnetic interaction to the $\eta$-${\eta }^{\prime }$ mixing angle is shown to be only about 3\%.

   hep-phInt.J.Mod.Phys.A(2026)·0 citations
3. 03*

   Scale dependence improvement of the quartic scalar field thermal effective potential in the optimized perturbation theory

   Lucas G. Câmara🇧🇷 · Marcus Benghi Pinto🇧🇷 · Rudnei O. Ramos🇧🇷

   Perturbation theory, as well as most thermal field resummation methods widely used to study finite-temperature quantum field theories, presents a non-negligible renormalization scale dependence. To address this limitation, we propose an alternative method that combines the renormalization group improvement prescription for the thermal effective potential with the optimized perturbation theory variational resummation technique. Here, we apply this new framework, termed variational renormalization group, to evaluate the effective potential of the scalar $\lambda {\varphi }^4$ theory at finite temperatures, which represents a benchmark model for phase transition studies. We show that the proposed approach significantly improves scale stability, compared to the use of optimized perturbation theory alone, across key thermodynamic quantities, including the effective potential, critical temperature, and pressure. These results establish the variational renormalization group as a robust alternative tool for precision studies of thermal phase transitions, with direct implications for cosmological applications (e.g., early-Universe thermodynamics) and condensed matter systems.

   hep-phhep-thPRD(2026)·2 citations
4. 04*

   Self-Interaction Controls Vortex Scale in Soliton Mergers

   Yuanyuan Zeng🇨🇳 · Bokai Zhang🇨🇳 · Jiajun Chen🇨🇳

   This study investigates the impact of self-interaction strength on the formation and scale of turbulent vortex structures during the merger of Bose stars, using numerical simulations of the Gross-Pitaevskii-Poisson (GPP) equations. We find that vortex formation is a universal outcome of soliton mergers, with the vortex size strongly dependent on the self-interaction coupling parameter $g$. Through analysis of velocity correlations, kinetic energy spectra, and vorticity distributions, we conclude that for repulsive self-interaction, the vortex region expands as self-interaction strength increases; conversely, for attractive self-interaction, the vortex region shrinks as self-interaction strength increases.

   hep-phPRD(2026)·3 citations
5. 05*

   Exclusive $\mathrm{J}/\psi$ production off a dilute proton within a refined hotspot description

   Heikki Mäntysaari (1 and 2)🇫🇮 · Anh Dung Le (1 and 2) ((1) Department of Physics, University of Jyväskylä, Finland, (2) Helsinki Institute of Physics, Finland)

   We revisit the calculation of exclusive $\mathrm{J}/\psi$ production in electron-proton scattering within the QCD dipole model, employing a refined description of the proton in terms of gluonic hot spots in the dilute regime. In contrast to earlier studies, we incorporate key missing elements: the event-by-event fluctuations in both the number of hot spots and their local saturation scales, as well as the first relativistic corrections to the $\mathrm{J}/\psi$ wave function. We perform a Bayesian analysis to constrain the model parameters using HERA data. These enhancements significantly improve the agreement with HERA data. Saturation scale fluctuations are found to be more important than fluctuations in the number of hot spots. Including the first relativistic correction is found to be important, especially in order to describe the observed power-law behavior in the incoherent cross section at large $t$.

   hep-phPRD(2025)·3 citations
6. 06*

   Plasminos in chiral QCD plasma

   Sourav Duari🇮🇳 · Nilanjan Chaudhuri🇮🇳 · Sourav Sarkar · Pradip Roy🇮🇳

   The quark self-energy in a hot and dense QCD medium with local chiral imbalance shows additional structures. Evaluated using the hard thermal loop approximation this leads to distinct dispersion relations for left and right handed quark quasi-particle and plasmino modes.

   hep-phEPJA(2026)·2 citations
7. 07*

   Indirect dark matter searches with neutrino telescopes via energetic cosmic showers

   Arindam Basu🇮🇳 · Basabendu Barman🇮🇳 · Arindam Das🇯🇵

   We explore the possibility that the high energy neutrino flux observed by terrestrial telescopes originates from dark matter (DM) annihilation. Specifically, we study a minimal, UV-complete $U(1)$ extension of the Standard Model with a Dirac DM candidate, whose annihilation into neutrinos proceeds exclusively through a $Z^{\prime }$ boson. By computing the annihilation cross section and comparing with the observed flux, we derive bounds on the model parameters. Additional constraints are obtained within the freeze-in framework, where the observed relic abundance is reproduced, leading to the strongest bounds. Considering cosmic string vibrations as a source of gravitational waves, we further constrain the vacuum expectation value of the $U(1)$ breaking. All results are contrasted with perturbativity limits and existing constraints from low- and high-energy experiments.

   hep-phastro-ph.COastro-ph.HEPLB(2026)·1 citation
8. 08*

   Particle Collisions & Quantum Entanglement in High-Energy Collisions

   Emidio Gabrielli🇮🇹

   The exploration of fundamental quantum phenomena, such as entanglement and Bell inequality violations$-$extensively studied in low-energy regimes$-$has recently extended to high-energy particle collisions. Experimentally, Bell inequality violations, which challenge Einstein's principle of local realism, were first observed in low-energy entangled photon systems by A. Aspect, J. F. Clauser, and A. Zeilinger, earning them the 2022 Nobel Prize in Physics. Particle colliders provide a novel setting for probing quantum information theory, operating at energies over ten orders of magnitude higher than previous experiments and in the presence of electroweak and strong interactions. Additionally, collider detectors offer unique advantages for quantum state reconstruction via quantum state tomography. This book chapter reviews key theoretical and experimental advancements in this emerging field, highlighting its challenges, objectives, and potential impact on both quantum information theory and high-energy physics.

   hep-phhep-exquant-phContribution to the book Particle Acceler…·2 citations
9. 09*

   Electromagnetic Leptogenesis -- an EFT-Consistent Analysis via Wilson Coefficients. Part I. Low-Scale, Non-Resonant Regime

   Rin Takada🇯🇵

   We analyse electromagnetic leptogenesis within the framework of an effective field theory, where the dynamics is governed by the gauge-invariant dipole operator $O_{NB}$. The Wilson coefficient $C_{NB}$ is matched at one loop and renormalisation-group (RG) evolved to the electroweak scale. After electroweak symmetry breaking we compute flavour-dependent two-body decay widths and CP asymmetries for $N\to \nu +\gamma /Z$, and solve the fully flavoured Boltzmann equations. In the $N_1$-dominated regime the freeze-out baryon asymmetry is $Y_B^{\mathrm{FO}}\lesssim 10^{-17}$, far below the observed value $Y_B^{\mathrm{obs}}\simeq 8.7\times 10^{-11}$. The suppression is structural: gauge invariance forces a Higgs insertion; therefore dipole couplings $\mu \propto v/M_{\Psi }^2$ while the matched coefficient $C_{NB}$ is loop-generated and further reduced by RG running. We note that in the quasi-degenerate limit the self-energy resonance can be operative and suggest a plausible path to $Y_B^{\mathrm{obs}}$.

   hep-phJHEP(2025)·2 citations
10. 10*

    Evidence of Relationships Among Fundamental Constants of the Standard Model

    S. V. Chekanov🇺🇸 · H. Kjellerstrand🇨🇴

    This paper presents an approach to reducing the number of fundamental parameters in the Standard Model (SM) using genetic programming, a machine learning technique based on evolutionary algorithms. We outline the core principles of our method and identify the simplest analytic relationships among SM parameters. Our results suggest that the SM parameters associated with quark and boson masses are not randomly distributed, but instead follow a hierarchical structure within a high-dimensional functional space. The found analytic solution depends on only two input parameters, representing the simplest mathematical model that could provide a foundation for developing a future theoretical framework to address the SM.

    hep-ph2 citations
11. 11*

    Predictions for $R_{AA}$ in 5.36 TeV C+C, O+O, and Ne+Ne collisions at the LHC

    B.G. Zakharov🇷🇺

    Experiments on collisions of light nuclei at $\sqrt{s}=5.36$ TeV have recently begun at the LHC. In this regard we make predictions for nuclear modification factor $R_{AA}$ in 5.36 TeV C+C, O+O, and Ne+Ne collisions for scenarios with and without quark-gluon plasma formation in $pp$ collisions. We find a sizeable difference in $R_{AA}$ for these two scenarios, which grows with decreasing atomic number. This says that data on $R_{AA}$ for light nuclei could potentially give information on the presence of jet quenching in $pp$ collisions.

    hep-phnucl-thPisma Zh.Eksp.Teor.Fiz.(2025)·2 citations
12. 12*

    General finite two-loop amplitude integrand for photoproduction in quark annihilation

    Charalampos Anastasiou🇨🇭 · Julia Karlen🇨🇭 · Roshni Sahoo🇨🇭 · George Sterman🇺🇸 · Matilde Vicini🇨🇭

    The construction of integrands free of infrared and ultraviolet singularities may enable the application of numerical methods to evaluate loop amplitudes that are inaccessible with analytic techniques. At two loops, finite amplitude integrands have been constructed for the production of off-shell or massive colorless particles via quark annihilation. In this article, we extend this class of processes to include real photons in the final state. To achieve this, we introduce appropriate momentum flows and counterterms to eliminate singularities that occur because the photons are massless. These singularities arise only locally at the integrand level and do not lead to divergences upon integration. Our treatment also eliminates all power singularities arising from self-energy corrections in the integrand. We extend the analysis to gluon emission from virtual quarks. We believe these new insights will be useful for future extensions of infrared subtraction methods to processes with final-state jets.

    hep-phhep-th8 citations
13. 13*

    Potential of the reaction $e^{+}{e}^{-}\to p\bar{p}{\pi }^0$ for constructing higher $\rho$-meson spectroscopy above 2.4 GeV

    Dan Guo🇨🇳 · Jun-Zhang Wang🇨🇳 · Qin-Song Zhou🇨🇳

    The spectrum of light unflavored vector mesons above 2.4 GeV has not yet been firmly established experimentally. In this work, we demonstrate that the process $e^{+}{e}^{-}\to p\bar{p}\pi$ serves as a particularly promising channel as a probe for higher isovector $\rho$ excitations. In contrast to typical electron-positron annihilation processes into purely light-meson final states, the reaction $e^{+}{e}^{-}\to p\bar{p}\pi$ benefits from a relatively low continuum background, on the order of $(50\sim 100)\text{pb}$ around 2.4 GeV, which enhances the visibility of even modest resonance contributions. In addition, the comparatively high production threshold further suppresses potential contamination from lower $\rho$-meson excitations. Our analysis based on effective Lagrangian approach indicates that the observed lineshape of the $e^{+}{e}^{-}\to p\bar{p}\pi$ cross section measured by BESIII can be naturally interpreted by including the $\rho (5S)$ and $\rho (6S)$ contributions, namely the fourth and fifth radial excitations of $\rho (770)$. In particular, the pronounced rise of the cross section near 2.4 GeV provides strong evidence for the contribution of $\rho (5S)$ signal. Their branching ratios to the $p\bar{p}\pi$ final state are found to be below 4\%, which do not contradict with usual expectations. In addition, we evaluate pion-induced production of these two $\rho$-meson states as a complementary probe, offering useful guidance for the relevant experiments such as COMPASS.

    hep-phPRD(2025)·1 citation
14. 14*

    Jet cone size dependence of single inclusive jet suppression due to jet quenching in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV

    Qing-Fei Han🇨🇳 · Man Xie🇨🇳 · Han-Zhong Zhang🇨🇳

    Jet suppression in high-energy heavy-ion collisions results from jet energy loss and transverse-momentum broadening during jet propagation through the quark-gluon plasma (QGP). The jet cone size ($R$) dependence of this suppression offers crucial insights into the energy loss mechanisms and QGP transport properties. In our study, we implement a comprehensive approach within the perturbative QCD parton model that incorporates both elastic and inelastic energy loss mechanisms. For elastic processes the contribution from recoiling thermal partons reduces the net in-cone energy loss for a given jet radius. For inelastic processes, we account for the angular distribution of radiated gluons, the thermalization of soft gluons, and transverse-momentum broadening. Using this framework, we calculate the jet nuclear modification factors ($R_{AA}$) and their double ratios $R_{AA}(R=0.2-1.0)/R_{AA}(R=0.2)$, and systematically compare with ALICE, ATLAS and CMS data in 0-10\% and 30-50\% Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02~TeV. Numerical results show that $R_{AA}$ increases with the cone size $R$ because the in-cone energy loss decreases at larger radii. Specifically, as the radius $R$ grows, the probability for elastically scattered partons to escape the jet cone and the likelihood for radiated gluons to fall outside the cone both decrease, resulting in a net reduction of energy loss. The $R_{AA}$ double ratios are approximately unity for small radii ($R=0.4$ relative to $R=0.2$) and at high $p_{\mathrm{T}}\gtrsim 200$ GeV$/c$, in agreement with the data within uncertainties.

    hep-phPRC(2026)·1 citation
15. 15*

    Oscillation-Independent Probes of Neutrino Non-Standard Interactions from Supernovae

    Angela R. Beatty🇺🇸 · Anna M. Suliga🇺🇸 · Volodymyr Takhistov🇯🇵

    Extreme astrophysical environments provide unique laboratories for testing fundamental neutrino interactions. We present the first oscillation-independent astrophysical probe of nonstandard neutrino interactions (NSI), using coincident neutral-current signals across diverse detectors to break degeneracies that have long limited sensitivity reach. Using self-consistent NSI supernova simulations and flavor-independent neutral-current scattering we show that anti-correlated signatures between JUNO liquid scintillator and dark matter detectors such as DARWIN/XLZD, ARGO, or RES-NOVA enable clear discrimination between NSI and flavor-conversion effects. For a Galactic supernova at Betelgeuse distance our approach enables an independent probe of neutrino-quark NSI couplings in parameter space that can reach and extend beyond current terrestrial limits. This multidetector approach enables breaking degeneracies in terrestrial searches and is broadly applicable to a wide range of upcoming experiments, establishing a new principle for testing fundamental interactions with astrophysical data.

    hep-phastro-ph.HEhep-exPRD(2026)·2 citations
16. 16*

    Entropy and multiplicity of hadrons in the high energy limit within dipole cascade models

    Krzysztof Kutak🇵🇱 · Sándor Lökös🇵🇱

    We investigate and compare QCD dipole cascade models, the 1D Mueller dipole model, its high energy limit and its generalization that follows from studies of 1D systems with conformal symmetry. To address the ambiguity stemming from different definitions of the rapidity ranges in experimental measurements, we propose the entropy as the function of the logarithm of the average multiplicity, $S(\ln ⟨n⟩)$, as a universal observable. From the solutions of the models, we calculate both the entropy and the average charged particle multiplicity and compare to data measured in proton-proton collisions. We obtained these quantities directly from the measured multiplicity distributions and determine the model parameters via fits. We find that the generalized dipole model provides a significantly better description of the data than the 1D Mueller model.

    hep-phPRD(2025)·11 citations
17. 17*

    Lepton flavor violating decays of Higgs boson in the NB-LSSM

    Cai Guo🇨🇳 · Xing-Xing Dong🇨🇳 · Shu-Min Zhao🇨🇳 · Zhan Cao🇨🇳 · Jia-Peng Huo🇨🇳 · Jin-Lei Yang🇨🇳 · Tai-Fu Feng🇨🇳

    Lepton flavor violation (LFV) represents a clear new physics (NP) signal beyond the standard model (SM). NB-LSSM, the next to minimal supersymmetric extension of the SM with local B-L gauge symmetry, includes three Higgs singlets and three generations of right-handed neutrinos in the basis of MSSM, motivated by the new definition of SM-like Higgs resultly from the introducing of three Higgs singlets which mix with the two Higgs doublets at the tree level in the NB-LSSM. We calculate LFV processes $h\to l_i{l}_j$ in the mass eigenstate basis and the electroweak interaction basis separately, and the latter adopts the mass insertion approximation (MIA) method. In the suitable parameter space, we obtain the reasonable numerical results. At the same time, the corresponding constraints from the LFV rare decays $l_j\to l_i\gamma$ are considered to analyze the numerical results.

    hep-phEPJC(2025)·1 citation
18. 18*

    Influence of the nuclear magnetic field on electron-positron pair production in low-energy heavy-nuclei collisions

    N. K. Dulaev🇷🇺 · D. A. Telnov🇷🇺 · V. M. Shabaev🇷🇺 · Y. S. Kozhedub🇷🇺 · X. Ma🇨🇳 · I. A. Maltsev🇷🇺 · R. V. Popov🇷🇺 · I. I. Tupitsyn🇷🇺

    Total and energy-angle differential probabilities of positrons created in slow collisions of two identical nuclei are calculated within relativistic two-center approach. The time-dependent Dirac equation is solved in the rotating frame using the generalized pseudospectral method in modified prolate spheroidal coordinates. The magnetic interaction induced by the motion of the nuclei is included in the Hamiltonian. The rotational coupling term is also taken into account. Angle-integrated and angle-resolved energy spectra of the emitted positrons are calculated by projecting the propagated wave function onto positive-energy plane-wave states. Our results show that the magnetic interaction leads to a slight increase in the critical internuclear distance and enhances the total positron yield by up to several percent. However, it does not qualitatively alter the energy or angular distributions of emitted positrons. The angular distributions remain nearly isotropic. The characteristic supercritical regime signatures, found in previous works, are preserved.

    hep-phPRD(2025)·0 citations
19. 19*

    LHAASO Galactic Plane $\gamma$-rays Strongly Constrain Heavy Dark Matter

    Celine Boehm🇦🇺 · Ranjan Laha🇮🇳 · Tarak Nath Maity🇦🇺

    LHAASO, a ground-based observatory, is unveiling new frontiers in our understanding of high-energy $\gamma -$rays and cosmic rays. It has recently observed high energy diffuse $\gamma -$rays from the Galactic plane in the TeV-PeV range. For the first time, we analyze this data to search for signatures of heavy decaying and annihilating dark matter in the mass range $10^5-10^{11}$ GeV. We compute the expected photon flux from both Galactic and extragalactic dark matter, incorporating attenuation due to photon pair production. For the Galactic contribution, we include both prompt photons and secondary photons produced via inverse Compton scattering, accounting for electron/positron propagation. For the extragalactic component, in addition to the prompt and inverse Compton contributions, we also include cascade photons arising from inverse Compton scattering of pair-produced electrons and positrons. By combining all these contributions, we derive constraints on the dark matter parameter space. Our bounds for various two body Standard Model final states are strongest to date. This underscore LHAASO's capability to discover the nature of heavy dark matter.

    hep-phastro-ph.COhep-exJCAP(2026)·9 citations
20. 20*

    GUMP1.0 -- First global extraction of generalized parton distributions from experiment and lattice data with NLO accuracy

    Yuxun Guo🇺🇸 · Fatma P. Aslan🇺🇸 · Xiangdong Ji🇺🇸 · M. Gabriel Santiago🇺🇸

    We report the first global extraction of generalized parton distributions (GPDs), GUMP1.0, by combining deeply virtual Compton scattering and $\rho$-meson production data from Jefferson Lab and Hadron-Electron Ring Accelerator with global fits of parton distribution functions, charge form factors, and lattice quantum chromodynamics simulations. Using a conformal moment space parametrization, we achieve a unified description across low- and high-$x$ regions at next to leading order (NLO) accuracy in perturbative corrections. The results provide state-of-the-art GPDs consistent with almost all known facts, enabling three-dimensional nucleon imaging in impact parameter space and, at the same time, establishing a benchmark for future theoretical and experimental studies of the nucleon structure.

    hep-phhep-latnucl-exnucl-thPRL(2025)·37 citations
21. 21*

    Breaking Dark: Hunting Heavy Decaying Dark Matter with Tibet AS${}_{\gamma }$ and LHAASO-KM2A

    Abhishek Dubey🇮🇳 · Akash Kumar Saha🇮🇳

    Recent measurements of diffuse sub-PeV gamma-rays by the Tibet AS${}_{\gamma }$ and LHAASO collaborations have reshaped our understanding of the gamma-ray sky. Besides uncovering the nature of `PeVatrons', these measurements can also be used to probe the non-gravitational nature of dark matter. PeV-scale decaying dark matter can produce high-energy gamma rays in the final state and contribute to the measurements made by extensive air-shower detectors like Tibet AS${}_{\gamma }$ and LHAASO. Using the latest Tibet AS${}_{\gamma }$ upper limits on diffuse gamma rays away from the Galactic plane and the LHAASO-KM2A measurements of diffuse gamma rays from the Galactic plane, we put stringent constraints on lifetimes of decaying DM for masses $\sim 10^6-10^9$ GeV. Future observations of high-energy diffuse gamma-ray emission can thus provide stronger limits or potentially discover heavy decaying dark matter.

    hep-phastro-ph.COPRD(2026)·5 citations
22. 22*

    Testing Viability of Benchmark Dark Matter Models for the Galactic Center Excess

    Yongao Hu🇺🇸 · Cari Cesarotti🇺🇸 · Tracy R. Slatyer🇺🇸

    We examine the status of benchmark simplified dark matter models that have been proposed to explain the GeV gamma-ray Galactic Center excess. We constrain the available parameter space using updated observations from indirect detection, cosmology, direct detection, and accelerators. We show that there is still unconstrained parameter space in both classes of models we consider (a secluded dark sector with a vector portal coupling, and a two-Higgs doublet with a pseudoscalar mediator), and discuss the prospects for potential improvement of these constraints in future experiments.

    hep-phastro-ph.COastro-ph.HEJHEP(2026)·7 citations
23. 23*

    Imaging the Jet-Induced Medium Response with Energy Correlators

    Hannah Bossi🇺🇸 · Arjun Kudinoor🇺🇸 · Ian Moult🇺🇸 · Daniel Pablos🇪🇸 · Ananya Rai🇺🇸 · Krishna Rajagopal🇺🇸

    Quark-gluon plasma (QGP), when viewed at length scales of order the inverse of its temperature, behaves as a strongly-coupled liquid. However, when it is probed with sufficiently high momentum transfer, asymptotic freedom mandates the presence of quark- and gluon-like quasi-particles. High energy partons within jets can trigger these high-momentum exchanges, making jets valuable probes for revealing the presence of such quasi-particles. Such elastic scatterings are implemented in the Hybrid Model, where a jet parton that scatters is deflected, kicking a medium parton, which recoils. Before and after a scattering, as one and then both partons propagate through the medium, they lose energy and momentum, exciting wakes in the QGP droplet. We use two-point and three-point energy-energy correlators (EECs) to reveal the relevant angular regions at which (modified) parton showers and wakes in the QGP each dominate, offering a new way with which to visualize and constrain the corresponding dynamics. We compare our calculations to recent CMS and ALICE measurements of two-point EECs of charged-particle tracks in jets produced in PbPb collisions. We show that our calculations are closest to the experimental measurements when elastic scattering is included and when the elastically scattered recoil-partons produce their own wakes. We also propose a new variant of the measurement that is especially sensitive to jet wakes.

    hep-phnucl-exnucl-thEPJ Web Conf.(2026)·3 citations
24. 24*

    Forecasting Generative Amplification

    Henning Bahl🇩🇪 · Sascha Diefenbacher🇺🇸 · Nina Elmer🇩🇪 · Tilman Plehn🇩🇪 · Jonas Spinner🇩🇪

    Generative networks are perfect tools to enhance the speed and precision of LHC simulations. Especially when generating events beyond the size of the training dataset, it is important to understand their statistical precision. We present two complementary methods to estimate the amplification factor without large holdout datasets. Averaging amplification uses Bayesian networks or ensembling to estimate amplification from the precision of integrals over given phase-space volumes. Differential amplification uses hypothesis testing to quantify amplification without any resolution loss. Applied to state-of-the-art event generators, both methods indicate that amplification is already possible in specific regions of phase space.

    hep-phcs.LGSciPost Phys.(2026)·8 citations
25. 25*

    Constraining Effective Field Theories for dark matter candidates annihilating into gamma-ray lines with CTAO

    Lucia Angel🇧🇷 · Debasish Borah🇮🇳 · Jacinto P. Neto🇧🇷 · Farinaldo S. Queiroz🇧🇷 · Vitor de Souza🇧🇷

    Gamma-ray lines constitute a smoking gun signature for annihilating dark matter particles. Imaging Atmospheric Cherenkov Telescopes and satellites have searched for such signals but null results have been reported thus far. We take advantage of the expected gamma-ray flux sensitivity of the Cherenkov Telescope Array Observatory (CTAO) toward the direction of the Galactic Centre and Dwarf Galaxies and its exquisite energy resolution to derive upper limits on fermionic and scalar dark matter annihilations into gamma-ray lines. We consider the lowest-order effective operators for scalar and fermion dark matter, and derive limits on the energy scale using the recent CTAO projected sensitivity. Putting our findings into perspective with existing limits from direct and indirect detection experiments, we conclude that CTAO will either play a complementary role or be a discovery channel for dark matter signals.

    hep-phhep-exhep-thJCAP(2026)·1 citation
26. 26*

    Bayesian Analysis of the Neutron Star Equation of State and Model Comparison: Insights from PSR J0437+4715, PSR J0614+3329, and Other Multi-Physics Data

    Sk Md Adil Imam🇨🇱 · N. K. Patra🇨🇳

    We perform a comprehensive Bayesian analysis to constrain the neutron star (NS) equation of state (EoS) using a wide range of terrestrial and astrophysical data. The terrestrial inputs include quantities related to symmetric nuclear matter (SNM) and symmetry energy up to two times saturation density (${\rho }_0\sim$0.16 fm${}^{-3}$), derived from finite nuclei and heavy-ion collisions (HICs). The astrophysical constraints incorporate NS radii and tidal deformabilities from recent NICER observations and GW170817, respectively. We consider five different EoS models: Taylor, $n/3$, Skyrme, RMF, and sound speed(CS), are analyzed by sequentially updating the priors with (i) $\chi$EFT based pure neutron matter, (ii) terrestrial, empirical and earlier astrophysical data, (iii) case (ii) including NICER radii of PSR J0437+4715 and J0614+3329, (iv) all data combined, and (v) excluding empirical nuclear inputs. We also perform Bayesian model comparison which favors the Skyrme model under all combined data (scenario (iv)), yielding tight constraints on symmetry energy parameters: $L_0=56\pm 3$~MeV, $K_{\mathrm{sym}0}=-132\pm 15$~MeV and also on SNM parameters: $K_0=265\pm 12$~MeV, $Q_0=-366\pm 43$~MeV. The mass-radius and mass-tidal deformability posterior distributions are also well constrained. The radius and tidal deformability of a $1.4M_{\odot }$ neutron star are found to be $R_{1.4}=11.85\pm 0.11$~km and ${\Lambda }_{1.4}=354\pm 25$, respectively.

    ↳ nucl-thastro-ph.HEastro-ph.SRgr-qc+1PRD(2025)·7 citations
27. 27*

    Non-Abelian Casimir energy in the Curci-Ferrari model through a functional approach

    David Dudal🇧🇪 · Philipe De Fabritiis🇧🇷 · Sebbe Stouten🇧🇪

    Using functional integral methods, we investigate the non-Abelian Casimir energy in the Curci-Ferrari model, which offers an effective description of the infrared regime of Yang-Mills theory. We consider a 3+1D (resp.\ 2+1D) system of two infinite parallel plates (resp.\ wires) at a fixed distance from each other, with either perfect magnetic conductor (PMC) or perfect electric conductor (PEC) boundary conditions. Imposing the boundary conditions directly in the functional integral by the introduction of suitable auxiliary fields that act as Lagrange multipliers, we obtain a boundary effective action that captures the dynamics of this system. The Casimir energy is then computed both directly from the functional integral and via the energy-momentum tensor, providing equivalent results. We find that the Casimir energy for PEC and PMC conditions differs by a constant factor, which can be traced back to a van Dam--Veltman--Zakharov-like discontinuity (both in 3+1D and 2+1D). Lastly, we show that our analytical results are compatible with a variety of recent numerical lattice simulations of the non-perturbative Yang-Mills Casimir energy, in which a novel non-perturbative mass scale emerges.

    ↳ hep-thhep-lathep-phJHEP(2026)·5 citations
28. 28*

    Directed searches for gravitational waves from ultralight vector boson clouds around merger remnant and galactic black holes during the first part of the fourth LIGO-Virgo-KAGRA observing run

    The LIGO Scientific Collaboration · the Virgo Collaboration · the KAGRA Collaboration: A. G. Abac🇩🇪 · I. Abouelfettouh🇺🇸 · F. Acernese🇮🇹 · K. Ackley🇬🇧 · C. Adamcewicz🇦🇺 · S. Adhicary🇺🇸 · D. Adhikari · N. Adhikari · R. X. Adhikari · V. K. Adkins🇺🇸 and 1759 other authors

    We present the first directed searches for long-transient and continuous gravitational waves from ultralight vector boson clouds around known black holes (BHs). We use LIGO data from the first part of the fourth LIGO-Virgo-KAGRA observing run. The searches target two distinct types of BHs and use two new semicoherent methods: hidden Markov model (HMM) tracking for the remnant BHs of the mergers GW230814_230901 and GW231123_135430 (referred to as GW230814 and GW231123 in this study), and a dedicated method using the Band Sampled Data (BSD) framework for the galactic BH in the Cygnus X-1 binary system. Without finding evidence of a signal from vector bosons in the data, we estimate the mass range that can be constrained. For the HMM searches targeting the remnants from GW231123 and GW230814, we disfavor vector boson masses in the ranges $[0.94,1.08]$ and $[2.75,3.28]\times 10^{-13}$ eV, respectively, at 30% confidence, assuming a 1% false alarm probability. Although these searches are only marginally sensitive to signals from merger remnants at relatively large distances, future observations are expected to yield more stringent constraints with high confidence. For the BSD search targeting the BH in Cygnus X-1, we exclude vector boson masses in the range $[0.85,1.59]\times 10^{-13}$ eV at 95% confidence, assuming an initial BH spin larger than 0.5.

    ↳ gr-qcastro-ph.HEhep-phPRD(2026)·19 citations
29. 29*

    Uncertainty in Hadronic Diffuse $\gamma$-Ray Emission from the Temporal Stochasticity of Cosmic-Ray Sources

    Xing-Jian Lv🇨🇳 · Xiao-Jun Bi🇨🇳 · Kun Fang🇨🇳 · Han-Xiang Hu🇨🇳 · Peng-Fei Yin🇨🇳 · Meng-Jie Zhao🇨🇳

    Diffuse $\gamma$-ray emission is a key probe of cosmic rays (CRs) distribution within the Galaxy. However, the discrepancies between observations and theoretical model expectations highlight the need for refined uncertainty estimates. In the literature, spatial and temporal variability of lepton flux has been discussed as an uncertainty in diffuse $\gamma$-ray estimation. In the present work, we demonstrate that variability in the high energy CR hadron flux is an important, yet previously underappreciated, source of uncertainty in diffuse $\gamma$-ray estimates. To assess this effect, we perform fully three-dimensional, time-dependent GALPROP simulations of CR protons injected from discrete Galactic sources. Our results reveal that the uncertainty in the hadronic component of diffuse $\gamma$ rays is non-negligible and can be comparable to, or even exceed, current experimental uncertainties at very high energies. This finding challenges the conventional assumption that only leptonic fluctuations are relevant to diffuse $\gamma$-ray modeling.

    ↳ astro-ph.HEhep-phApJ(2026)·0 citations
30. 30*

    K-nonizing

    Jose Beltrán Jiménez🇪🇸 · Teodor Borislavov Vasilev🇪🇸 · Darío Jaramillo-Garrido🇪🇸 · Antonio L. Maroto🇪🇸 · Prado Martín-Moruno🇪🇸

    We unveil the dynamical equivalence of field theories with non-canonical kinetic terms and canonical theories with a volume element invariant under transverse diffeomorphisms. The proof of the equivalence also reveals a subtle connection between the standard Legendre transformation and the so-called Clairaut equation. Explicit examples of canonizable theories include classes of $k$-essence, non-linear electrodynamics, or $f(R)$ theories. The equivalence can also be extended to the class of mimetic theories.

    ↳ gr-qcastro-ph.COhep-phPLB(2026)·3 citations
31. 31*

    Inflationary Decoherence from the Gravitational Floor

    C.P. Burgess🇨🇦 · R. Holman🇺🇸 · Greg Kaplanek🇺🇸

    We re-examine the decoherence rate of primordial fluctuations within minimal inflationary models, using only the gravitational interactions required for the underlying fluctuation-generation mechanism itself. Since gravity provides the weakest interactions the result provides a plausible floor on the rate of primordial decoherence. Previous calculations ({\tt arXiv:2211.11046}) did so using only a subset of these interactions, motivated by assuming both system and environment were super-Hubble. We extend this by including the effects on super-Hubble modes of {\it all} gravitational interactions amongst scalar fluctuations at leading order in $H/\text{Mp}$ (and so need not restrict the decohering environment to being super-Hubble). We show how the decohering evolution becomes Markovian for super-Hubble modes, without the need to appeal to truncations (like the `rotating wave' approximation) that are often used in optics but can be inapprorpriate for cosmology. We find that the dominant contribution comes from the nonlocal cubic interactions obtained by solving the constraints. We find a decoherence rate that grows in the super-Hubble regime {\it faster} than found earlier and identify its leading divergent and finite parts. We argue why the divergent parts must cancel with other competing contributions -- such as decoherence due to environmental tensor modes -- that are partially computed elsewhere (and for which a complete calculation is in progress). We discuss the steps required to resum this result to late times and briefly discuss why they are more complicated than for earlier calculations.

    ↳ gr-qcastro-ph.COhep-phhep-thJCAP(2026)·11 citations
32. 32*

    A dense dark matter core of the subhalo in the strong lensing system JVAS B1938+666

    Lei Lei🇨🇳 · Yi-Ying Wang🇨🇳 · Qiao Li🇨🇳 · Jiang Dong · Ze-Fan Wang🇮🇷 · Wei-Long Lin · Yi-Ping Shu · Xiao-Yue Cao · Da-Neng Yang🇺🇸 · Yi-Zhong Fan🇨🇳

    The nature of dark matter remains unknown, motivating the study of fuzzy/wave dark matter (FDM/$\psi$DM) and self-interacting dark matter (SIDM) as alternative frameworks to address small-scale discrepancies in halo profiles inferred from observations. This study presents a non-parametric reconstruction of the mass distribution of the previously-found, dark subhalo in the strong-lensing system JVAS B1938+666. Compared with the standard Navarro-Frenk-White (NFW) profile, both SIDM and $\psi$DM ($m_{\psi }=1.32_{-0.31}^{+0.22}\times 10^{-22}\mathrm{eV}$) provide significantly better fits to the resulting density profile. Moreover, the SIDM model is favored over $\psi$DM with a Bayes factor of 14.44. The reconstructed density profile features a characteristic kiloparsec-scale core ($r_c\approx 0.5\mathrm{kpc}$) with central density ${\rho }_c\approx 2.5\times 10^7{\mathrm{M}}_{\odot }\mathrm{kp}{\mathrm{c}}^{-3}$, exhibiting remarkable consistency with the core-halo mass scaling relations observed in Local Group dwarf spheroidals. These findings offer insights that may help address the core-cusp discrepancy in $\Lambda$CDM substructure predictions.

    ↳ astro-ph.COastro-ph.GAastro-ph.HEgr-qc+1ApJL(2025)·8 citations
33. 33*

    Testing the Heterotic String with the Axion-Photon Coupling

    Mario Reig🇬🇧 · Timo Weigand🇩🇪

    The discovery of an axion-like particle above the QCD line would rule out Grand Unified Theories, including the perturbative heterotic string with the Standard Model embedded in a single $E_8$ factor or $SO(32)$. In this work we study a possible loophole to this observation, given by compactifications of the $E_8\times E_8$ heterotic string with a non-standard embedding of the Standard Model into the 10-dimensional gauge group. If electromagnetism is embedded into both $E_8$ factors, axions can couple to photons via the anomaly without coupling to QCD. We obtain upper bounds to the coupling-to-mass ratio $g_{a\gamma }/m_a$ for these axion-like particles as a function of the supersymmetry breaking scale and the unified gauge coupling. To be compatible with the measured gauge couplings and the weak mixing angle ${\sin }^2{\theta }_w$ at low-energies, phenomenologically viable models with non-standard $U(1{)}_Y$ embedding require sizeable one-loop threshold corrections from string states and/or charged matter at intermediate energy scales. We study how these effects modify the tree-level upper bounds to $g_{a\gamma }/m_a$ and show that, in the perturbative regime, they reduce the leading order estimates. Axion-like particles far above the QCD line are only possible in certain models where perturbation theory is lost. The main conclusion is that the discovery of an axion violating the bounds found in this work would be incompatible with large classes of otherwise phenomenologically viable string models, including the perturbative heterotic $SO(32)$ and $E_8\times E_8$ string, the type-I string, and certain heterotic M-theories. The role of small gauge instantons and worldsheet instantons in making some of the axion-like particles heavy and cosmologically relevant is briefly discussed.

    ↳ hep-thhep-phJHEP(2026)·20 citations
34. 34*

    Similarities in the evaporation of saturated solitons and black holes

    Giacomo Contri🇩🇪 · Gia Dvali🇩🇪 · Otari Sakhelashvili🇦🇺

    It has been suggested some time ago that many black hole properties are not specific to gravity, but rather are shared by a large class of objects, the so-called saturons, that saturate the quantum field theoretic upper bound on microstate degeneracy. By now, various aspects of this universality have been understood and demonstrated in a number of explicit examples. In the present paper, we add one more brick to the building by showing that the decay of a simple two-dimensional saturated soliton copies some key aspects of the black hole decay as well as of the information retrieval. In particular, we study the evaporation process of a classically-stable vacuum bubble of a spontaneously broken $SU(N)$-symmetry, coupled to massless fermions. We show that the decay rate as well as the characteristic energy of the emitted quanta are given by the inverse size of the object, in striking similarity with the Hawking evaporation of a black hole. The time-scale of information retrieval also matches the one previously suggested for a black hole by Page. We give the semiclassical derivation of the phenomenon as well as its fully quantum resolution as a decaying coherent state of Goldstone bosons. The universal nature of the effect and its microscopic understanding support the analogous quantum portrait of a black hole as a saturated coherent state of gravitons.

    ↳ hep-thgr-qchep-phPRD(2025)·7 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.