Mon·Jan 27, 2025Monday·January 27, 2025

1. 01*

   Looking for new strategies to probe low mass axion-like particles in ultraperipheral heavy-ion collisions at the LHC

   Pedro Nogarolli🇧🇷 · Victor P. Gonçalves🇧🇷 · Murilo S. Rangel🇧🇷

   The possibility of searching for long-lived axion-like particles (ALPs) decaying into photons is investigated in ultraperipheral $PbPb$ collisions at the Large Hadron Collider (LHC). We propose a search strategy for low mass ALPs using the LHCb and ALICE experiments. The ALP identification is performed by requiring the decay vertex be reconstructed outside the region where a primary vertex is expected, which strongly suppress the contribution associated with the decay of light mesons. We also use the fact that a fraction of the photons convert into electron-positron pairs, allowing the reconstruction of the particle decay position. We present the predictions for the pseudo - rapidity and transverse momentum distributions of the ALPs and photons. Moreover, predictions for the fiducial cross-sections, derived considering the characteristics of the ALICE and LHCb detectors, are presented for different values of the ALP mass and the ALP - photon coupling.

   hep-phhep-exUniverse(2025)·1 citation
2. 02*

   On the scalar sector of 2HDM: ring of basis invariants, syzygies, and six-loop renormalization-group equations

   A.V. Bednyakov🇷🇺

   We consider a generating set of reparametrization invariants that can be constructed from the couplings and masses entering the scalar potential of the general Two-Higgs-Doublet Model (2HDM). Being independent of higgs-basis rotations, they generate a polynomial ring of basis invariants that represent the physical content of the model. Ignoring for the moment gauge and Yukawa interactions, we derive six-loop renormalization group equations (RGE) for all the invariants entering the set. We do not compute a single Feynman diagram but rely heavily on the general RGE results for scalar theories. We use linear algebra together with techniques from Invariant Theory. The latter not only allow one to compute the number of linearly independent invariants entering beta functions at a certain loop order (via Hilbert series) but also provide a convenient tool for dealing with polynomial relations (so-called syzygies) between invariants from the generating set.

   hep-phJHEP(2025)·9 citations
3. 03*

   Study on axial fields in the dynamically assisted Schwinger effect

   Chengpeng Yu🇯🇵

   The dynamically assisted Schwinger effect, the generation of fermion-antifermion pairs in vacuum under a strong, slow-varying field and a weak, high-frequency field, has become a promising avenue to probe the vacuum structure and the nonlinear dynamics of QED. However, the role of axial fields in this phenomenon has remained underexplored. This study aims at analyzing how spatial axial fields influence particle production in the dynamically assisted Schwinger effect. Employing the high-frequency effective theory based on the Floquet-Magnus expansion, we demonstrate that a spatial axial field can occur as the effective field of a circular polarized high-frequency plane wave and significantly increase the number of fermions produced across different timescales. This enhancement offers both theoretical insights and useful tools for the experimental implementation of the Schwinger effect.

   hep-phnucl-thPRD(2025)·0 citations
4. 04*

   The effect of non-standard interactions and environmental decoherence at DUNE

   Chinmay Bera🇮🇳 · K. N. Deepthi🇮🇳 · Rukmani Mohanta🇮🇳

   The Deep Underground Neutrino Experiment (DUNE) is a proposed long-baseline neutrino oscillation experiment that will project an on-axis wide-band neutrino beam over a distance of 1300 km to determine the unknowns in the neutrino sector. Given the baseline of 1300 km and the intense beam facility, DUNE is a promising experiment to study the sub-leading effects such as environmental decoherence, matter induced non-standard interactions (NSIs), neutrino decay, etc. In this study, we investigate how NSI and environmental decoherence affect the neutrino oscillation probabilities simultaneously. Considering the modified probabilities we obtain the updated mass hierarchy (MH) and CP violation (CPV) sensitivities of DUNE. Furthermore, we demonstrate the sensitivity of DUNE to distinguish between the effects of NSI and environmental decoherence.

   hep-phJHEP(2025)·4 citations
5. 05*

   Study ${\Xi }_c^{+}\to \Lambda {\bar{K}}^0{\pi }^{+}$ and search for the low-lying baryons $\Xi (1/2^{-})$ and $\Sigma (1/2^{-})$

   Ying Li🇨🇳 · Wen-Tao Lyu🇨🇳 · Guan-Ying Wang🇨🇳 · Longke Li🇨🇳 · Wen-Cheng Yan🇨🇳 · En Wang🇨🇳

   Since searches for the low-lying excited baryons $\Xi (1/2^{-})$ and $\Sigma (1/2^{-})$ are crucial to deepening our understanding of the light baryon spectrum, we have investigated the Cabibbo-favored process ${\Xi }_c^{+}\to \Lambda {\bar{K}}^0{\pi }^{+}$ by taking into account the $S$-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach, which could dynamically generate the resonances $\Xi (1/2^{-})$ and $\Sigma (1/2^{-})$. The contributions from the excited kaons are double Cabibbo-suppressed, and the contribution from the $\Sigma (1385)$ is also suppressed due to Korner-Pati-Woo theory, thus those states are expected to play negligible contributions in this process. We have predicted the ${\bar{K}}^0\Lambda$ and ${\pi }^{+}\Lambda$ invariant mass distributions, which have the clear signals of the $\Xi (1/2^{-})$ and $\Sigma (1/2^{-})$. Thus, the ${\Xi }_c^{+}\to \Lambda {\bar{K}}^0{\pi }^{+}$ is an ideal process to search for the low-lying baryons $\Xi (1/2^{-})$ and $\Sigma (1/2^{-})$, and we make a call for a precise measurements of this process in experiments, such as Belle II, LHCb, and the proposed Super Tau-Charm Facility (STCF).

   hep-phPRD(2025)·13 citations
6. 06*

   Can one-loop corrections to the one-gluon exchange potential adequately describe the charmed meson spectrum?

   A. Capelo-Astudillo🇪🇨 · T. Aguilar🇪🇨 · M. Conde-Correa🇪🇨 · A. Duenas-Vidal🇪🇨 · P. G. Ortega🇪🇸 · J. Segovia🇪🇸

   We investigate the charmed meson spectrum using a constituent quark model (CQM) with one-loop corrections applied to the one-gluon exchange (OGE) potential. The study aims to understand if the modified version of our CQM sufficiently account for the charmed meson spectrum observed experimentally, without invoking exotic quark and gluon configurations such as hybrid mesons or tetraquarks. Within this model, charmed mesons' masses are computed, comparing theoretical predictions to experimental data. The results, within uncertainties, suggest that our theoretical framework generally reproduces mass splittings and level ordering observed for charmed mesons. Particularly, large discrepancies between theory and experiment found in $P$-wave states are, at least, significantly ameliorated by incorporating higher-order interaction terms. Therefore, the findings emphasize that while the traditional quark model is limited in fully describing charmed mesons, enhanced potential terms may bridge the gap with experimental observations. The study contributes a framework for predicting excited charmed meson states for future experimental validation.

   hep-phhep-exhep-latnucl-ex+1Symmetry(2025)·2 citations
7. 07*

   Very Special Relativity: Cherenkov Effect and an Analogy with Minkowski's Electrodynamics of Continuous Media

   I. H. Brevik🇳🇴 · M. M. Chaichian🇫🇮 · B. A. Couto e Silva🇫🇮 · B. L. Sánchez-Vega🇧🇷

   In this work, we explore the implications of the Cohen and Glashow Very Special Relativity (VSR) theory, a framework that introduces Lorentz invariance violation through the presence of a preferred direction. Our analysis focuses on the impact of VSR on the Cherenkov angle, revealing modifications to the dispersion relation of particles, particularly the photon and the electron, which acquire an effective inertial mass. This modification also implies a deviation in the speed of light, which can be constrained through precise experimental measurements. Using data from the RICH system of the LHCb experiment, we take advantage of its capability to reconstruct Cherenkov angles within the momentum range of the particles of 2.6-100 GeV/c. These measurements, combined with the most stringent laboratory tests of the isotropy of the speed of light ($\Delta c/c\sim 10^{-17}$), allow us to impose new upper bounds on the parameter $\Omega$, which quantifies a deviation from the standard Special Relativity. Furthermore, we establish an analogy between VSR and Minkowski's electrodynamics in a dielectric medium for particles with very high velocity, offering a physically intuitive interpretation of the parameter $\Omega$.

   hep-phEPJC(2025)·0 citations
8. 08*

   Automated NLO calculations for asymmetric hadron-hadron collisions in MadGraph5_aMC@NLO

   Carlo Flore🇮🇹 · Daniel Kikoła🇵🇱 · Aleksander Kusina🇵🇱 · Jean-Philippe Lansberg🇫🇷 · Olivier Mattelaer🇧🇪 · Anton Safronov🇵🇱

   We have extended {\tt MadGraph5\_aMC@NLO} capabilities by implementing computations for asymmetric hadron-hadron collisions, including proton-nucleus, pion-hadron or nucleus-nucleus collisions in order to obtain a tool for automated perturbative computations of cross sections (or ratios of cross sections) in asymmetric reactions at next-to-leading (NLO) order in ${\alpha }_S$ in collinear factorisation. This tool, like the original symmetric version of \texttt{MadGraph5\_aMC@NLO}, automatically computes cross sections for different factorisation and renormalisation scales and PDFs provided by the {\tt LHAPDF} library, thereby allowing for an easy assessment of the associated theoretical uncertainties. In this paper, we present the validation of our code using $W$ and $Z$ boson production in $p$Pb collisions and Drell-Yan-pair production in $\pi W$ collisions. We also illustrate the capabilities of the framework by providing cross section and nuclear modification factors with their uncertainties for the production of $W$ and $Z$ bosons, charm and bottom quarks as well as associated production of $b\bar{b}+H^0$ in $p$Pb collisions at the LHC.

   hep-phhep-exnucl-exnucl-thEPJA(2025)·4 citations
9. 09*

   Decaying scalar dark matter in the minimal left-right symmetric model

   P. S. Bhupal Dev🇺🇸 · Julian Heeck🇺🇸 · Anil Thapa🇺🇸

   In the minimal left-right symmetric theory, the dark matter candidate is usually ascribed to the lightest right-handed neutrino. Here we present an alternative decaying dark matter candidate in this model in terms of the lightest neutral scalar from the $SU(2{)}_R$-triplet field. This setup requires a vast hierarchy between the scalar mass and the left-right symmetry breaking scale, which renders the scalar dark matter sufficiently stable on cosmological time scales. The stability of the dark matter imposes constraints on the right-handed neutrino mass, which has consequences for the neutrino mass generation, as well as for leptogenesis. Although somewhat fine-tuned, it provides a very economical scenario wherein the minimal left-right model can simultaneously explain dark matter, neutrino masses, and the matter-antimatter asymmetry of the Universe.

   hep-phPRD(2025)·8 citations
10. 10*

    My friends and my path in physics

    Mirzayusuf Musakhanov🇺🇿

    Dedication to my untimely departed friends, Dmitry Igorevich Diakonov, Viktor Yur'evich Petrov and Maxim Vladimirovich Polyakov.

    hep-phphysics.hist-phActa Phys.Polon.B(2025)·0 citations
11. 11*

    Triple Higgs Boson Production with Two Heavy Scalars at the LHC via a Simplified Approach

    Andreas Papaefstathiou🇺🇸 · Gilberto Tetlalmatzi-Xolocotzi🇩🇪

    We investigate triple Higgs boson production at the CERN LHC, in models containing two new heavy neutral scalar particles. We apply a simplified factorized approach in the narrow-width approximation to double-resonant triple Higgs boson production, and demonstrate that relevant constraints can be derived on models with extended scalar sectors, during the high-luminosity phase of the LHC. We also find, within an explicit two-real-singlet model and for the cut-based 6 $b$-jet analysis considered here, that the double-resonant contribution captures the dominant features of the signal, while non-resonant components have a limited impact on the expected sensitivity. The method therefore provides a fast approximate framework for models in which triple Higgs boson production is dominated by a narrow double-resonant topology.

    hep-phhep-exEPJC(2026)·4 citations
12. 12*

    Theoretical Predictions for the Inner Dark Matter Distribution in the Milky Way Informed by Simulations

    Abdelaziz Hussein🇺🇸 · Lina Necib🇺🇸 · Manoj Kaplinghat🇺🇸 · Stacy Y. Kim🇺🇸 · Andrew Wetzel🇺🇸 · Justin I. Read🇬🇧 · Martin P. Rey🇬🇧 · Oscar Agertz🇸🇪

    We build a theoretical range for the Milky Way's (MW) inner dark matter (DM) distribution informed by the FIRE-2, Auriga, VINTERGATAN-GM, and TNG50 simulation suites assuming the canonical cold dark matter (CDM) model. The DM density profiles in Auriga, VINTERGATAN-GM, and TNG50 can be approximately modeled using the adiabatic contraction prescription of Gnedin et al. 2004, while FIRE-2 has stronger baryonic feedback, leading to a departure from the adiabatic contraction model. The simulated halos that are adiabatically contracted are close to spherical (axis ratio $q\in [0.75-0.9]$ at $5^{\circ }$), whereas halos that experience strong baryonic feedback are oblate ($q\in [0.5-0.7]$). Using the adiabatic contraction and strong baryonic feedback models, along with the observed stellar distribution of the MW, the inner logarithmic density slope for CDM in the MW is predicted to range from $-0.5$ to $-1.3$. The $J$-factor, which determines the DM-annihilation flux, averaged over a solid angle of $5^{\circ }$ ($10^{\circ }$) is predicted to span the range $0.8$-$30$ ($0.6$-$10$) $\times 10^{23}{\mathrm{GeV}}^2/{\mathrm{cm}}^5$. The $D$-factor, which determines the flux due to DM decay, is predicted to be in the range $0.6$-$2$ ($0.5-1$) $\times 10^{23}\mathrm{GeV}/{\mathrm{cm}}^2$. GitHub: The results for this work can be found at https://github.com/abdelazizhussein/MW-Inner-DM-Profile.

    hep-phastro-ph.GA23 citations
13. 13*

    Ephemeral Oscillons in Scalar-Tensor Theories: The Higgs-like case

    Matteo Piani🇵🇹 · Javier Rubio🇪🇸 · Francisco Torrenti🇪🇸

    We investigate the post-inflationary evolution of a non-minimally coupled inflaton field in scalar-tensor theories, framed within the flexible framework of Einstein-Cartan gravity. By focusing on a class of simplified Higgs-like scenarios, we simulate the transition from the end of inflation to the formation of oscillons using fully-fledged 3+1 classical lattice simulations. Once oscillons form, we extract their profiles and perform 1+1 simulations to evolve their radial equations. Our findings reveal that these oscillons, unlike typical cases in the literature, are relatively short-lived, due to the presence of self interactions at small field values. The radiation produced by this novel type of oscillons can quickly lead to a radiation-dominated Universe, even in the absence of additional fields or interactions. Finally, we leverage our results to derive precise predictions for the inflationary observables and the produced spectrum of gravitational waves associated with oscillon formation. Significantly, our study establishes also an upper bound on the duration of the heating phase in Einstein-Cartan Higgs inflation scenarios.

    hep-phastro-ph.COgr-qcJCAP(2025)·11 citations
14. 14*

    Grassmann Tensor Renormalization Group for two-flavor massive Schwinger model with a theta term

    Hayato Kanno🇺🇸 · Shinichiro Akiyama🇯🇵 · Kotaro Murakami🇯🇵 · Shinji Takeda🇯🇵

    We investigate the $N_f=2$ Schwinger model with the massive staggered fermions in the presence of a $2\pi$ periodic $\theta$ term, using the Grassmann tensor renormalization group. Thanks to the Grassmann tensor network formulation, there is no difficulty in dealing with the massive staggered fermions. We study the $\theta$ dependence of the free energy in the thermodynamic limit. Our calculation provides consistent results with the analytical solution in the large mass limit. The results also suggest that the $N_f=2$ Schwinger model on a lattice has a different phase structure from that described by the continuum theory.

    ↳ hep-lathep-phhep-thPoS(2025)·1 citation
15. 15*

    Excitations of gauge bosons, and other aspects of gauge Higgs theories

    Jeff Greensite🇺🇸

    I review the qualitative physical distinction between the Higgs and confinement phases of a gauge Higgs theory, and the non-local order parameter introduced by Matsuyama and myself which identifies the two phases. I then present some new results suggestive of a possible excitation spectrum of vector bosons in the electroweak sector of the Standard Model.

    ↳ hep-lathep-phPoS(2025)·1 citation
16. 16*

    Study of the gamma-Ray Radiation Properties of High-redshift Blazars at z>2.5

    Fan Wu · Benzhong Dai🇨🇳

    We study a sample of 30 high-redshift blazars ($z>2.5$) by means of spectra and the radiation mechanism with Fermi Large Area Telescope $\gamma$-ray observations spanning 15 years. Three models -- the power law, power law with an exponential cutoff, and log-parabola -- are employed to analyze the spectral properties, and most sources exhibit significant curvature. The high-redshift blazars exhibit higher $\gamma$-ray luminosities and softer spectral indices compared with their low-redshift counterparts, where B3~1343+451 has the highest integrated flux, $1.13\times 10^{-7}\mathrm{ph}\mathrm{c}{\mathrm{m}}^{-2}{\mathrm{s}}^{-1}$. We use a standard one-zone leptonic emission model to reproduce the spectral energy distributions of 23 sources with multiwavelength observations. We find that modeling with infrared seed photons is systematically better than with broad-line region (BLR) photons based on a ${\chi }^2$ test, which suggests that the $\gamma$-ray-emitting regions are most likely located outside the BLR. The fit results show that high-redshift blazars exhibit higher energy density, jet power, kinetic power, and accretion disk luminosities, along with lower synchrotron and inverse Compton (IC) peak frequencies, relative to their lower-redshift counterparts. We find that blazars with higher accretion disk luminosities tend to have lower IC peak frequencies, leading to more efficient cooling of high-energy electrons. The positive correlation between jet power and accretion disk luminosity further supports the possibility of an accretion-jet connection in these high-redshift sources.

    ↳ astro-ph.HEhep-ph0 citations
17. 17*

    Resolution requirements for numerical modeling of neutrino quantum kinetics

    Hiroki Nagakura🇯🇵 · Masamichi Zaizen🇯🇵 · Jiabao Liu🇯🇵 · Lucas Johns🇺🇸

    Neutrino quantum kinetics is a rapidly evolving field in computational astrophysics, with a primary focus on collective neutrino oscillations in core-collapse supernovae and post-merger phases of binary neutron star mergers. In recent years, there has been considerable debate concerning resolution dependence in numerical simulations. In this paper, we conduct a comprehensive resolution study in both angular- and spatial directions by using two independent schemes of quantum kinetic neutrino transport: finite volume and pseudospectral methods. We complement our discussion by linear stability analysis including inhomogeneous modes. Our result suggests that decreasing spatial resolutions underestimates the growth of flavor instability, and then leads to wrong asymptotic states of flavor conversions, which potentially has a critical impact on astrophysical consequences. We further delve into numerical results of low resolution simulations, that reveals the underlying mechanism responsible for numerical artifacts caused by insufficient resolutions. This study settles the debate on requirements of resolutions and serves as a guideline for numerical modeling of quantum kinetic neutrino transport.

    ↳ astro-ph.HEhep-phPRD(2025)·21 citations
18. 18*

    Theoretical study of the $\Sigma N$ cusp in the $K^{-}d\to \pi \Lambda N$ reaction

    Shunsuke Yasunaga🇯🇵 · Daisuke Jido🇯🇵

    The $K^{-}d\to \pi \Lambda N$ reaction is useful for exploring the hyperon-nucleon interaction through final state interactions. In particular, the cusp structure of the $\Lambda N$ invariant mass spectrum at the $\Sigma N$ threshold contains information about the s-wave interaction of 1/2-isospin hyperon-nucleon systems. The calculation of the spectrum is performed with the aim of extracting the scattering length of the $\Sigma N(I=1/2)$ channel that couples to the $\Lambda N$ channel from this reaction, and the results are discussed in comparison with experimental data to highlight the factors that should be considered.

    ↳ nucl-thhep-phPoS(2025)·1 citation
19. 19*

    Longitudinal flow decorrelations in light ion collisions

    Hadi Mehrabpour🇨🇳 · Abhisek Saha🇨🇳

    This study presents a detailed analysis of longitudinal flow decorrelations in light ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider(LHC) energies for the first time. We compare different theoretical models of the oxygen structure and find that certain observables, such as the flow vector correlator, can distinguish between them, particularly highlighting differences between the variational Monte Carlo (VMC) structure and other models, such as Nuclear Lattice Effective Field Theory (NLEFT) and the Projected Generator Coordinate Method (PGCM), which behave similarly. We further examine flow decorrelations across different systems, including d+Au and O+O collisions at 200 GeV, as well as Ne+Ne and O+O collisions at 6.37 TeV, indicating a hierarchy in decorrelations that underscores the complexity of these interactions. Our findings emphasize that the role of asymmetry in d+Au collisions and its impact on flow correlations is mitigated using a modified flow correlation defined as a ratio of two flow vector covariances derived from different pairs of pseudorapidity bins. Additionally, our analysis of flow angle decorrelations shows diverse distributions across various systems, finding distinct patterns in d+Au collisions compared to other collision systems.

    ↳ nucl-thhep-phnucl-exEPJC(2025)·6 citations
20. 20*

    Deciphering the spectral bumps of Galactic cosmic rays through gamma-ray observations of nearby molecular clouds

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

    The observed spectral bump in cosmic-ray (CR) proton and helium spectra, along with the phase and amplitude evolution of CR dipole anisotropy, provide plausible yet indirect evidence for the presence of a nearby CR source. This study investigates the potential of giant molecular clouds (GMCs) located near the solar system to act as natural probes of CRs from the nearby source, with their gamma-ray emissions serving as indicators of spatial variations in CR flux within the solar neighborhood resulting from this source. We show that a nearby source, accounting for the CR data, could imprint distinct features on the $\gamma$-ray spectra of different GMCs. We expect that these features are detectable by LHAASO and upcoming high-energy $\gamma$-ray observatories, providing a powerful test for the hypothesized nearby source. Notably, we find that determining the energy dependence of the $\gamma$-ray spectral index offers a promising approach to investigate the nearby source and constrain its distance. Conversely, if the spectral bump is a widespread Galactic phenomenon, the energy dependence would exhibit uniformity across all GMCs, distinguishing the underlying mechanism accounting for the spectral bump from the scenario involving a nearby source.

    ↳ astro-ph.HEhep-phPRD(2025)·1 citation
21. 21*

    Primordial gravitational waves from spontaneous Lorentz symmetry breaking

    Mohsen Khodadi🇮🇷 · Gaetano Lambiase🇮🇹 · Leonardo Mastrototaro🇮🇹 · Tanmay Kumar Poddar🇮🇹

    We study the effect of Spontaneous Lorentz Symmetry Breaking (SLSB) on Primordial Gravitational Waves (PGWs) generated during inflation. The SLSB is induced by a time-like Bumblebee vector field which is non-minimally coupled to the Ricci tensor in the Friedmann-Lemaître-Robertson-Walker background. The power spectrum and GW amplitude are computed to investigate how Lorentz violation leaves observable imprints. We calculate the GW strain amplitude over frequencies $(10^{-10}\mathrm{Hz},10^4\mathrm{Hz})$, for a range of the dimensionless Lorentz-violating parameter, $-10^{-3}\le l\le 10^{-4}$, which essentially comes from a slight sensitivity to the equation of state for dark energy. For positive $l$ values, the amplitude of GW shows a mild suppression compared to the standard cosmological scenario $(l=0)$. This effect could be observable with detectors like SKA, $\mu$-Ares, and BBO. Conversely, negative $l$ values amplify the GW amplitude, enhancing detectability by both SKA, $\mu$-Ares, and BBO, as well as by THEIA and DECIGO. Notably, the GW strain amplitude increases by an order of magnitude as $l$ moves from 0 to $-10^{-3}$, improving prospects for detection in high-sensitivity detectors like THEIA and DECIGO.

    ↳ astro-ph.COgr-qchep-phPLB(2025)·11 citations
22. 22*

    Two-Loop Master Integrals for Mixed QCD-EW Corrections to $gg\to H$ Through $\mathcal{O}({ϵ}^2)$

    Robin Marzucca🇨🇭 · Andrew J. McLeod🇬🇧 · Christoph Nega🇩🇪

    We consider mixed strong-electroweak corrections to Higgs production via gluon fusion, in which the Higgs boson couples to the top quark. Using the method of differential equations, we compute all of the master integrals that contribute to this process at two loops through $\mathcal{O}({ϵ}^2)$ in the dimensional regularization parameter $ϵ=(d-4)/2$, keeping full analytic dependence on the top quark, Higgs, W, and Z boson masses. We present the results for these master integrals in terms of iterated integrals whose kernels depend on elliptic curves.

    ↳ hep-thhep-phPRD(2025)·19 citations
23. 23*

    Probes of flavour symmetry and violation with top quarks in ATLAS and CMS

    Miriam Watson (on behalf of the ATLAS and CMS Collaborations)🇬🇧

    Results are presented of searches and measurements in the top quark sector by the ATLAS and CMS experiments. These analyses use data from proton-proton collisions at a centre-of-mass energy of 13 TeV, recorded during Run 2 at the Large Hadron Collider and corresponding to integrated luminosities of 138-140 fb${}^{-1}$. Searches are carried out for charged lepton flavour violation, baryon number violation and the presence of neutral heavy leptons. A precise measurement of lepton flavour universality between electrons and muons originating from top quark-antiquark events is also presented.

    ↳ hep-exhep-phSciPost Phys.Proc.(2026)·1 citation
24. 24*

    ALP production from light primordial black holes: The role of superradiance

    Marco Manno🇮🇹 · Daniele Montanino🇮🇹

    Light primordial black holes (LPBHs) with masses in the range $10$~g~$\le M_{\mathrm{BH}}\le 10^9$~g, although they evaporate before Big Bang Nucleosynthesis, can play a significant role in the production of both dark matter and dark radiation. In particular, LPBHs can evaporate into light axions or axion-like particles (ALPs) with masses $m_a\lesssim$~MeV, contributing to the effective number of neutrino species, $\Delta N_{\mathrm{eff}}$. Additionally, heavy scalar particles known as {\em moduli}, predicted by string theory, can be produced both via Hawking evaporation and through amplification by a mechanism called {\em superradiant instability} in the case of spinning primordial black holes (PBHs). These moduli can subsequently decay into ALPs, further amplifying their abundance. In this work, we calculate the number density of ALPs in the presence of moduli enhanced by superradiance for Kerr PBHs. Using current limits on $\Delta N_{\mathrm{eff}}$ from Planck satellite observations, we derive updated constraints on this scenario.

    ↳ astro-ph.COastro-ph.HEhep-phPRD(2025)·6 citations
25. 25*

    Effects of the Lorentz symmetry violation on relativistic neutral scalar bosons: Scattering and bound states

    Luis B. Castro🇧🇷 · Antonio S. de Castro🇧🇷

    In this letter, we investigate the effects of Lorentz symmetry violation on a relativistic neutral scalar boson within the framework of the Klein-Gordon formalism. We consider a tensor $(K_F{)}_{\mu \nu \alpha \beta }$ out of the Standard Model Extension, which describes the field configuration consisting of a constant magnetic field $\vec{B}=B\hat{z}$ and a cylindrical electric field $\vec{E}=\frac{\lambda }{r}\hat{r}$. We analyze and discuss the effects of Lorentz symmetry violation on the equation of motion and show that the presence of a specific Lorentz symmetry violation parameter is essential to obtain analytical solutions for scattering and bound states. Employing the partial wave approach in cylindrical coordinates, we calculate the relativistic phase shift, scattering amplitude and $S$-matrix, and discuss the effects of Lorentz symmetry violation on the phase shift. Furthermore, we obtain bound-state solutions by examining the poles of the $S$-matrix and compare our findings with those reported in the literature. Our results reveal that bound-state solutions are only feasible for a restrict range of Lorentz symmetry violation parameters, which contradict previous studies.

    ↳ hep-thhep-phmath-phmath.MP+1EPL(2025)·1 citation
26. 26*

    How deep is the dip and how tall are the wiggles in inflationary power spectra?

    Vadim Briaud🇫🇷 · Alexandros Karam🇪🇪 · Niko Koivunen🇪🇪 · Eemeli Tomberg🇪🇪 · Hardi Veermäe🇪🇪 · Vincent Vennin🇫🇷

    We study linear scalar perturbations in single-field models of inflation featuring a non-attractor phase. These models lead to a peak in the curvature power spectrum that may result in the formation of primordial black holes. We develop a transfer-matrix formalism, analogous to the S-matrix program in quantum-field theory, that maps perturbations throughout the transitory phase. At scales smaller than the peak, the power spectrum features damped oscillations, and the duration of the transition sets the scale at which power-law damping switches to exponential damping. At scales larger than the peak, we demonstrate that a dip appears in the power spectrum if and only if the inflaton's velocity does not flip sign. We show that the amplitude at the dip always scales as the inverse square-rooted amplitude of the peak, and comment on the physical consequences of this universal relationship. We also test the robustness of our results with a few toy models and interpret them with an intuitive mechanical analogy.

    ↳ astro-ph.COgr-qchep-phJCAP(2025)·17 citations
27. 27*

    Super-Kamiokande Strongly Constrains Leptophilic Dark Matter Capture in the Sun

    Thong T.Q. Nguyen🇸🇪 · Tim Linden🇸🇪 · Pierluca Carenza🇸🇪 · Axel Widmark🇸🇪

    The Sun can efficiently capture leptophilic dark matter that scatters with free electrons. If this dark matter subsequently annihilates into leptonic states, it can produce a detectable neutrino flux. Using 10 years of Super-Kamiokande observations, we set constraints on the dark-matter/electron scattering cross-section that exceed terrestrial direct detection searches by more than an order of magnitude for dark matter masses below 100 GeV, and reach cross-sections as low as $\sim$4$\times$10${}^{-41}$cm${}^{-2}$.

    ↳ astro-ph.HEastro-ph.SRhep-phPRD(2026)·25 citations
28. 28*

    Gamma-Ray Observations of Galaxy Clusters Strongly Constrain Dark Matter Annihilation in Prompt Cusps

    Milena Crnogorčević🇸🇪 · M. Sten Delos🇺🇸 · Nadia Kuritzén🇸🇪 · Tim Linden🇸🇪

    Thermal dark matter models generically include the prompt creation of highly-concentrated dark matter cusps in the early Universe. Recent studies find that these cusps can survive to the present day, as long as they do not fall into extremely dense regions of baryonic structure. In this work, we build models of dark matter annihilation within the prompt cusps that reside in galaxy clusters, showing that they dominate the total $\gamma$-ray annihilation signal. Using 15 years of Fermi-LAT data, we find no evidence for a $\gamma$-ray excess from these sources, and set strong constraints on annihilating dark matter. These constraints generically rule out the thermal annihilation cross-section to the $b\bar{b}$ channel for dark matter masses below $\sim$200~GeV.

    ↳ astro-ph.HEastro-ph.COhep-phPRD(2025)·8 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.