Wed·Aug 27, 2025Wednesday·August 27, 2025

1. 01*

   Reduction of Feynman Integrals in the Parametric Representation IV: Integrals with Irregular Integration Regions

   Wen Chen🇨🇳

   Parametric Feynman integrals with the regions of integration defined by some polynomials are considered in this paper. It is shown that integrals with irregular integration regions can be converted to standard parametric integrals, for which a reduction method is known. An application of this method to the analytic calculation of three-point energy correlators is presented. In principle, this method applies to more general event shapes and even jet observables.

   hep-phhep-thmath-phmath.MP2 citations
2. 02*

   Evaluating the ratio of the exclusive vector meson photoproduction to inclusive hadron/jet production cross section in ultraperipheral heavy ion collisions

   Joao Vitor C. Lovato🇧🇷 · Edgar Huayra🇧🇷 · Magno V.T. Machado🇧🇷

   Using the QCD color dipole picture to study exclusive vector meson and inclusive jet/open meson photoproduction, we calculate the ratio of elastic meson production to inclusive hadron production cross sections for ultraperipheral heavy ion collisions. Predictions are evaluated for run 4 of the Large Hadron Collider in proton-nucleus ($pA$) and nucleus-nucleus ($AA$) collisions. The dependencies of the ratio on jet/hadron transverse momentum and atomic number are investigated. The double ratio $R_{\mathrm{UPC}}$ for $AA$ over $pA$ collisions is also computed, which has been previously proposed as a new observable probing parton saturation physics.

   hep-phhep-exPLB(2026)·0 citations
3. 03*

   Searching for the Leptophilic Gauge Boson Z${}_l$ at Future $e^{+}{e}^{-}$ Colliders

   S. O. Kara🇹🇷

   We study the discovery prospects of the leptophilic photon Z\_l, a hypothetical gauge boson beyond the Standard Model, at future electron-positron colliders. Our analysis is based on the process e+e- -> mu+mu- and consistently includes realistic effects such as initial state radiation and beamstrahlung. Using the benchmark parameters of FCC-ee, CEPC, ILC, and CLIC, we demonstrate the complementarity of circular and linear colliders: circular machines achieve excellent sensitivity to very small couplings, down to g\_l ~ 10^{-4}, while high-energy linear colliders extend the search reach into the TeV domain.

   hep-ph2 citations
4. 04*

   Comparing Calculations of Seasonal Variations of Atmospheric Muons in Deep Underground Detectors

   Amanda Alves · Lilly Pyras🇩🇪 · Dennis Soldin🇺🇸 · Stef Verpoest🇺🇸

   Cosmic rays interact with nuclei in the Earth's atmosphere to produce extensive air showers, which give rise to the atmospheric muon flux. Temperature fluctuations in the atmosphere influence the rate of muons measured in deep underground experiments. This contribution presents predictions of the daily muon flux at a depth of 2000 m.w.e., calculated using MUTE, a software tool which combines MCEq, a numerical solver of the matrix cascade equations in the atmosphere, with PROPOSAL, a propagation code for leptons in matter. The flux estimates are obtained assuming different cosmic-ray flux and hadronic interaction models. The results are compared to previous approaches, based on different methods, to calculate seasonal variations of atmospheric muons in deep underground detectors.

   hep-phastro-ph.HEPoS(2025)·0 citations
5. 05*

   Gravitational $D$-Form Factor: The $\sigma$-Meson as a Dilaton confronted with Lattice Data

   Roy Stegeman🇬🇧 · Roman Zwicky🇬🇧

   We investigate the nucleon and pion gravitational $D$-form factors, by fitting a $\sigma /f_0(500)$-meson pole, together with a background term, to lattice data at $m_{\pi }\approx 170\text{MeV}$. We find that the fitted residues are compatible with predictions from dilaton effective theory. In this framework, the $\sigma$-meson takes on the role of the dilaton, the Goldstone boson of spontaneously broken scale symmetry. These results support the idea that QCD may be governed by an infrared fixed point and offer a physical interpretation of the $D$-form factor (or $D$-term) in the soft limit.

   hep-phhep-lathep-thnucl-thJHEP(2026)·22 citations
6. 06*

   One texture zero for Dirac neutrinos in a diagonal charged lepton basis

   Richard H. Benavides🇨🇴 · Yessica Lenis🇨🇴 · John D. Gómez🇨🇴 · William A. Ponce🇨🇴

   An analytic and numerical systematic study of the neutrino mass matrix with one texture zero is presented in a basis where the charged leptons are diagonal. Under the assumption that neutrinos are Dirac particles, the analysis is carried out in detail for the normal and inverted hierarchy mass spectrum. Our study is performed without any approximations, first analytically and then numerically, using current neutrino oscillation data. The analysis constrains the parameter space in such a way that, among the six possible one-texture-zero patterns, only four are favored in the normal hierarchy and, one in the inverted hierarchy, by current oscillation data at the $3\sigma$ level. Phenomenological implications for the lepton CP-violating phase and neutrino masses are also explored.

   hep-phCPC(2026)·0 citations
7. 07*

   $Z_4$ scotogenic model with a Higgs portal

   Noel Jonathan Jobu🇮🇳 · Kenji Nishiwaki🇮🇳

   We propose a new Scotogenic type model based on a global $Z_4$ symmetry involving dark matter candidates. After the symmetry breaking as $Z_4$ to $Z_2$ via the singlet scalar vacuum expectation value (VEV), the lightest Majorana fermion works as a viable thermal freeze-out dark matter (DM) candidate, and the mass terms for active neutrinos are generated as a finite quantum correction at the 1-loop level. A key point of realising our Scotogenic structure is to introduce two types of Majorana fermions (heavy right-handed neutrinos) and inert Higgs doublets with opposite $Z_4$ parities. Since a large VEV for the singlet scalar is not so harmful in an appropriate realisation of the Higgs mechanism for the SM gauge symmetry, we can naturally realise a TeV-scale fermionic DM candidate, where constraints via direct detection experiments are less than those for sub-TeV DM. Our scenario involves the Higgs-portal DM interactions, which help the realisation of the correct DM relic abundance. Relying on the structure of the model, it is possible to find a natural partner for coannihilation. Our scenario can be investigated via the measurement of the Higgs trilinear self-coupling at the Large Hadron Collider. The simplest way to evade the domain-wall problem by adding a tiny soft $Z_2$ breaking term works, keeping a sufficient longevity of the decaying DM lifetime.

   hep-phhep-exPRD(2025)·3 citations
8. 08*

   Decays of ${\rm Y}(10860)$ and ${\rm Y}(10753)$ into $\omega {\chi }_{bJ}$

   Zheng-Li Luo🇨🇳 · Yi-Lin Song🇨🇳 · Feng-Kun Guo🇨🇳

   In this paper, we model ${\rm Y}(10753)$ as a $4S$-$3D$ bottomonium mixture and ${\rm Y}(10860)$ as a $5S$-$4D$ mixture, and predict the properties of a new bottomonium state, ${\rm Y}(10950)$, as the mixing partner of ${\rm Y}(10860)$. The mixing angles are derived from dielectron decay widths and mass shifts of these bottomonia. We consider open-bottom meson loops in the decays of the $D$-wave bottomonium components, based on a nonrelativistic effective field theory power counting. We show that the $S$-$D$ mixing scheme is consistent with the experimental data of the decays of ${\rm Y}(10860)$ into $\omega {\chi }_{bJ}$ ($J=0,1,2$) and ${\rm Y}(10753)$ into $\omega {\chi }_{bJ}$ ($J=1,2$). Predictions for the dielectron widths and partial decay widths into ${\chi }_{bJ}\omega$ for ${\rm Y}(10753)$ and ${\rm Y}(10950)$ are presented.

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

   Structure of leptonic Yukawa couplings in the Zee model

   Chuan-Hung Chen🇹🇼

   The radiative neutrino mass matrix $m^{\nu }$ in the Zee model depends on leptonic Yukawa couplings $F$ to a singlet scalar and $Y^{\ell }$ to a new Higgs doublet. Leveraging the skew-symmetric structure of $F$, we derive a unique identity linking $F$ and $m^{\nu }$ that is explicitly independent of $Y^{\ell }$. This relation implies that five entries of $Y^{\ell }$ can, in principle, be determined directly from $m^{\nu }$ and $F$, while the remaining four can be selected based on phenomenological assumptions. As an illustration, we apply this framework to the two-zero texture $B2$, highlighting its enhancement of the muon $g-2$.

   hep-phhep-ex1 citation
10. 10*

    QGP@50: More than Four Decades of Jet Quenching

    Xin-Nian Wang🇨🇳 · Urs Achim Wiedemann🇨🇭

    How are high-momentum transfer processes modified when embedded in the Quark-Gluon Plasma (QGP) instead of the vacuum? How can fundamental properties of the QGP be inferred from their medium-modifications? And what can be learnt about QCD? These questions have motivated theoretical and experimental studies for more than four decades almost since the beginning of QGP research. Here we review with a historical perspective the main theoretical developments and the resulting interplay of theory and experiment at RHIC and at the LHC.

    hep-ph30 citations
11. 11*

    $\lambda$ and $\rho$ Regge trajectories for bottom-charm tetraquarks $(bq)(\bar{c}{\bar{q}}^{\prime })$ and $(cq)(\bar{b}{\bar{q}}^{\prime })$

    Jiao-Kai Chen🇨🇳 · He Song🇨🇳 · Xin-Ru Liu🇨🇳

    Using the newly proposed tetraquark Regge trajectory relations, we investigate three series of Regge trajectories for bottom-charm tetraquarks $(bq)(\bar{c}{\bar{q}}^{\prime })$ and $(cq)(\bar{b}{\bar{q}}^{\prime })$ with $q,q^{\prime }=u,d,s$: the ${\rho }_1$-, ${\rho }_2$-, and $\lambda$-trajectories. We provide rough estimates for the masses of the ${\rho }_1$-, ${\rho }_2$-, and $\lambda$-excited states. Except for the $\lambda$-trajectories, the complete forms of the other two series of Regge trajectories for bottom-charm tetraquarks are lengthy and cumbersome. We show that the ${\rho }_1$- and ${\rho }_2$-trajectories cannot be obtained by simply imitating meson Regge trajectories, because mesons have no substructures. To derive these trajectories, the tetraquarks' structure and substructure must be taken into consideration. Otherwise, the ${\rho }_1$- and ${\rho }_2$-trajectories would have to rely solely on fitting existing theoretical results or future experimental data. Consequently, the fundamental relationship between the slopes of the obtained trajectories and string tension would become unobvious, and the predictive power of the Regge trajectories would be compromised. Moreover, we show that the lengthy complete forms of the ${\rho }_1$- and ${\rho }_2$-trajectories can be well approximated by simple fitted formulas. For the bottom-charm tetraquarks $(bq)(\bar{c}{\bar{q}}^{\prime })$ and $(cq)(\bar{b}{\bar{q}}^{\prime })$, ${\rho }_1$- and ${\rho }_2$-trajectories exhibit a behavior of $M\sim x^{1/2}$ $(x=n_{r_1},n_{r_2},l_1,l_2)$, whereas $\lambda$-trajectories exhibit a behavior of $M\sim x^{2/3}$ $(x=N_r,L)$. All three series of trajectories display concave downward behavior in the $(M^2,x)$ plane when the confining potential is linear. This conclusion holds irrespective of whether light-quark masses are included, owing to the large masses of the heavy quarks.

    hep-phEPJC(2025)·4 citations
12. 12*

    Perturbative and nonperturbative aspects of neutrino oscillations in quantum field theory

    Massimo Blasone🇮🇹 · Luca Smaldone🇮🇹

    In this work, we present a comprehensive and pedagogical review of two quantum field theoretical approaches to neutrino flavor mixing and oscillations: the non-perturbative flavor Fock space formalism and the perturbative interaction picture framework.

    hep-phhep-th5 citations
13. 13*

    $T_{bc\bar{s}}$ states in the process ${\rm Y}\to D^{-}{\bar{B}}^0{D}_s^{+}$

    Wen-Ying Liu🇨🇳 · Hua-Xing Chen🇨🇳

    We perform a theoretical study of the decay process ${\rm Y}\to D^{-}{\bar{B}}^0{D}_s^{+}$ in search of the doubly heavy tetraquark states $T_{bc\bar{s}}$ with quark content $bc\bar{s}\bar{d}$. These $T_{bc\bar{s}}$ states are assumed to be dynamically generated molecular states from the S-wave interactions between ${\bar{B}}_s^{(\ast )0}{D}^{(\ast )+}$ and ${\bar{B}}^{(\ast )0}{D}_s^{(\ast )+}$ meson pairs. Based on the total angular momentum and the type of the constituent mesons (pseudoscalars $P$ or vectors $V$), they are labeled as $T_{bc\bar{s}}^{0,PP}$, $T_{bc\bar{s}}^{0,VV}$, and $T_{bc\bar{s}}^{2,VV}$, respectively. The ${\bar{B}}^0{D}_s^{+}$ invariant mass distribution for this decay is calculated using current algebra, incorporating contributions from $T_{bc\bar{s}}$ states arising from final-state interactions. Our results reveal a clear peak structure in the $7415-7425$ MeV region, which is attributed to the $T_{bc\bar{s}}^{2,VV}$ state. Additionally, a distinct dip structure appears near the ${\bar{B}}^{\ast 0}{D}_s^{\ast +}$ threshold, characteristic of the $T_{bc\bar{s}}^{2,VV}$ as a hadronic molecular state. A near-threshold enhancement associated with the $T_{bc\bar{s}}^{0,PP}$ state and a dip arising from the $T_{bc\bar{s}}^{0,VV}$ state are also identified, though the manifestation of these features depends sensitively on model parameter fine-tuning. Therefore, with increased experimental statistics, the decay channel ${\rm Y}\to D^{-}{\bar{B}}^0{D}_s^{+}$ offers a promising avenue for discovering and characterizing the $T_{bc\bar{s}}$ states.

    hep-phhep-exPRD(2025)·0 citations
14. 14*

    A simple algorithm for polarized parton evolution

    Stefan Höche🇺🇸 · Mareen Hoppe🇩🇪 · Daniel Reichelt🇨🇭

    We present an algorithm to include the correlation between the production and decay planes of gluons in a parton-shower simulation. The technique is based on identifying the charge currents responsible for the creation and annihilation of the vector field. It is applicable in both the hard-collinear and the soft wide-angle region. As a function of the number of particles, the algorithm scales linear in computing time and memory. We demonstrate agreement with fixed-order perturbative calculations in the relevant kinematical limits, and present a new observable that can be used to probe correlations beyond current-current interactions.

    hep-phPRD(2026)·5 citations
15. 15*

    Triple top baryon ${\Omega }_{ttt}$

    Zi-Qi Zhu🇨🇳 · Chang Xiong🇨🇳 · Yu-Jie Zhang🇨🇳

    The recent observation of toponium by CMS and ATLAS has renewed interest in top quark bound states. In this work, we present an exploratory but quantitative study of the hypothetical triple-top baryon, denoted as ${\Omega }_{ttt}$, the only baryon that is governed by ultraviolet freedom. Using a variational method with an effective potential of $ttt$ that includes QCD, Higgs, and QED contributions, we estimate its mass to be around 514 GeV with a binding energy of about 4 GeV. We further discuss its possible production at future high-energy colliders, finding that the cross sections are extremely suppressed. The dominant weak decay channel is identified as ${\Omega }_{ttt}\to W^{+}{W}^{+}{W}^{+}bbb$, leading to complex multi-lepton and multi-jet final states. Our analysis, though approximate, demonstrates the distinctive features of ${\Omega }_{ttt}$ compared with other triply-heavy baryons such as ${\Omega }_{ccc}$ and ${\Omega }_{bbb}$, and may serve as a starting point for more refined approaches, including lattice QCD or effective field theory. This work highlights both the theoretical challenges and the potential opportunities in probing the strong interaction at unprecedented mass scales.

    hep-ph4 citations
16. 16*

    Hits to Higgs: Hit-Level Higgs Classification from Raw LHC Detector Data Using Higgsformer

    Sascha Caron🇳🇱 · Polina Moskvitina🇳🇱 · Roberto Ruiz de Austri🇪🇸 · Eugene Shalugin🇳🇱

    We present Higgsformer, a transformer-based architecture that classifies Higgs events at the Large Hadron Collider directly from raw inner tracker hits, bypassing the traditional reconstruction chain of intermediate physics objects. As a benchmark, we focus on distinguishing $t\bar{t}H$ from $t\bar{t}$ events with $H\to b\bar{b}$, a particularly challenging task due to their similar final state topologies. Our pipeline begins with event generation in Pythia8, fast simulation with ACTS/Fatras, and classification directly from raw detector hits. We show for the first time that a transformer model originally developed for inner tracker hit-to-track assignment can be retrained to classify Higgs signal events directly from raw hits. For comparison, we reconstruct the same events with Delphes and train a Particle Transformer as an object-based classifier. We evaluate both approaches under varying dataset sizes and pileup levels. Despite relying exclusively on inner tracker hits, our large Higgsformer achieves an AUC of $0.855$, matching the performance of the traditional reconstruction pipeline at a $b$-tagging efficiency of $\approx 40\%$ under the same detector constraints.

    hep-phEPJC(2026)·1 citation
17. 17*

    Single pion-production and pion propagation in Achilles

    Joshua Isaacson🇺🇸 · William Jay🇺🇸 · Alessandro Lovato🇺🇸 · Pedro Machado🇺🇸 · Alexis Nikolakopoulos🇺🇸 · Noemi Rocco🇺🇸 · Noah Steinberg🇺🇸

    We extend the applicability of Achilles (A CHIcagoLand Lepton Event Simulator) by incorporating the single-pion production mechanism in a fully exclusive fashion. The electroweak interaction vertex is modeled by combining the state-of-the-art Dynamical Coupled-Channels approach with realistic hole spectral functions, which account for correlations in both the initial target state and the residual spectator system. Final-state interactions are treated using a semi-classical intranuclear cascade that leverages nuclear configurations to determine the correlated spatial distribution of protons and neutrons. The meson-baryon scattering amplitudes used in the cascade are computed within the Dynamical Coupled-Channels framework, consistent with the electroweak vertex. To model pion absorption, we employ the optical potential approach of Oset and Salcedo. As an alternative approach, we explicitly model the production and propagation of resonances which mediate pion-nucleon scattering and pion absorption. We validate out approach against pion-nucleon and pion-nucleus scattering data, and present comparisons with electron- and neutrino-nucleus measurements from e4$\nu$, T2K, MINER$\nu$A, and MicroBooNE.

    hep-phhep-exnucl-thPRD(2026)·5 citations
18. 18*

    Classification of color superconductivity by one-gluon exchange helicity amplitudes and renormalization group equations

    Yuki Fujimoto🇯🇵

    Quark matter at high baryon density exhibits diverse pairing patterns classified by color, flavor, and angular momentum quantum numbers. We compute one-gluon exchange (OGE) helicity amplitudes and introduce a nonrelativistic classification of the pairing channel, justified by the channel decomposition in a Lorentz-noninvariant medium and the decoupling of renormalization group flows at leading order. We find the new attractive channel in OGE; the medium effects can render the vacuum-repulsive color $6$ channel attractive in the spin-triplet sector. For color $\bar{3}$ with antisymmetric flavor, the dominant pairing is ${}^1{S}_0$, while for symmetric flavor the same-helicity ${}^1{P}_1$ prevails over ${}^3{S}_1$, revising the conventional single-flavor picture. With a mismatch of the Fermi momenta, ${}^1{S}_0$ channel, leading to color-flavor locked or two-flavor color superconductor, remains most stable when the separation is small, and the color-spin locked pairing becomes favored as the mismatch gets large. We suggest there are possible quark-hadron continuity in certain cases as expected in the literature.

    hep-phnucl-th1 citation
19. 19*

    The Quark Jet Function for $k_T$-like Variables in NNLO QCD

    Luca Buonocore🇨🇭 · Massimiliano Grazzini🇨🇭 · Flavio Guadagni🇨🇭 · Jürg Haag🇨🇭 · Luca Rottoli🇮🇹

    The precise description of jet processes requires observables capable of efficiently capturing the dynamics of the energy flow in hadronic final states. We consider a class of tranverse-momentum like resolution variables that smoothly describe the $n+1$ to $n$ jet transition in multi-jet processes. We discuss a general method for the computation of the corresponding quark jet function at next-to-next-to-leading order in perturbative QCD. Rapidity divergences are regulated by using a time-like auxiliary vector. We present explicit results for a variant of $y_{23}$ in the $E$-scheme and in the WTA scheme.

    hep-phEPJC(2025)·8 citations
20. 20*

    Two-flavored heavy-light mesons' nuclear bound states

    G. N. Zeminiani🇧🇷 · K. Tsushima🇧🇷

    We calculate the $B^{-}$-, $\overline{B^0}$-, $D^{+}$-, $D^0$-, $K^{-}$-, and $\overline{K^0}$-${}^{12}$C bound state energies by solving the Klein-Gordon (K;G.) equation in momentum space, and also obtain the corresponding coordinate space radial wave functions. The strong Lorentz scalar and vector potentials in ${}^{12}$C are calculated using a local density approximation, where the scalar potentials are obtained based on the mass shifts of the respective mesons in nuclear matter. The mesons' mass shifts, the ${}^{12}$C nuclear density distributions, the strong potentials as well as the Coulomb potentials, are calculated by the quark-meson coupling (QMC) model.

    ↳ nucl-thhep-exhep-phnucl-exPoS(2026)·0 citations
21. 21*

    Imprints of screened dark energy on nonlocal quantum correlations

    Fabiano Feleppa🇮🇹 · Gaetano Lambiase🇮🇹 · Sunny Vagnozzi🇮🇹

    We investigate how screening mechanisms, reconciling light scalar fields driving cosmic acceleration with local fifth force constraints, can be probed via their impact on non-local quantum correlations between entangled spin pairs, whose evolution on a curved background is affected by General Relativity (GR) and screened modified gravity effects. We consider a gedankenexperiment featuring a pair of massive, spin-1/2 particles orbiting the Earth, evaluating their non-local correlations through spin observables associated to the Clauser-Horne-Shimony-Holt (CHSH) inequality. Using a general formalism developed earlier for curved space-time spin evolution, we compute the effects of screening on the CHSH inequality, finding its degree of violation to be suppressed relative to the flat space-time case. Applying this formalism to the chameleon, symmetron, and dilaton mechanisms, we identify currently unconstrained regions of parameter space where the screening contribution is comparable to that of GR. While detecting these effects will be challenging, our work provides a proof-of-principle for testing screened dark energy through quantum non-locality.

    ↳ gr-qcastro-ph.COhep-phquant-phPRD(2025)·18 citations
22. 22*

    Axions, Three-Forms, and M-Theory

    Florian Niedermann🇸🇪 · Ziqi Yan🇸🇪

    Scalar fields with masses protected by global shift symmetries, commonly referred to as axions, are abundantly used in effective field theories in cosmology and particle physics. However, global symmetries cannot be expected to be protected at the fundamental level. Finding consistent ultra-violet completions for axions is therefore a necessity. In this work, we identify the axion with the position mode of a charged 3-brane in (4+1)-dimensions. The shift symmetry of the axion is then a residual diffeomorphism in the fifth dimension orthogonal to the brane. Meanwhile, the brane is coupled to a flux in the fifth dimension. From the (3+1)-dimensional perspective, this construction generates (perturbatively) a mass for the axion and matches previously known proposals in the literature based on the coupling between the axion and a three-form gauge field. In a second step, we uplift this (4+1)-dimensional model to M-theory, where the same three-form is found to couple to the membrane with a (2+1)-dimensional worldvolume. In particular, our proposal also elucidates the duality between the axion and a two-form gauge field in the literature. We show that this dual two-form couples to the boundary of an open membrane in M-theory. Finally, we comment on the relations to and differences from other closed and open string axion monodromy models.

    ↳ hep-thhep-phJHEP(2026)·2 citations
23. 23*

    Varying fundamental constants cosmography

    C. J. A. P. Martins🇵🇹

    Cosmography is a model-independent phenomenological approach to observational cosmology, relying on Taylor series expansions of physical quantities as a function of the cosmological redshift or other analogous variables. A recent work developed the formalism for a cosmographic analysis of astrophysical and local measurements of the fine-structure constant, $\alpha$, and provided first constraints on the corresponding parameters. Here we update the earlier work, both by including more recent measurements of $\alpha$, and by extending it to other fundamental dimensionless couplings. We find no statistically significant evidence for such variations, and place stringent constraints on the first two terms of all these cosmographic series: the linear coefficient in the $\alpha$ series is constrained to parts per billion level, thanks to recently improved atomic clock constraints, while the other coefficients are constrained to parts per million level. Additionally, we use the same data to place cosmographic constraints on models from a broad class of Grand Unified Theories in which varying fundamental constants occur, and highlight how future data can provide a discriminating cosmographic test between freezing and thawing dark energy models.

    ↳ astro-ph.COgr-qchep-phPhys.Dark Univ.(2025)·2 citations
24. 24*

    Impacts of axion cooling on the direct detection of supernova axions

    Kanji Mori🇯🇵 · Masamitsu Mori🇯🇵

    Core-collapse supernovae provide a unique opportunity to probe axions because they can be a copious source of the particles. It has recently been proposed that axion helioscopes can be used for the direct search for supernova axions if a supernova event appears within a few hundred parsecs. However, the event number of supernova axions has been estimated only within the post-process framework. In this study, we perform long-term supernova simulations for a 9.6M_sun star coupled with the axion emission to reevaluate the event number of axions detected by the helioscopes. We find that the additional cooling induced by the axion emission can significantly decrease the temperature in the proto-neutron star. As a result, the axion luminosity and hence the axion event number are reduced, compared with the result obtained through post-processing. Our result indicates that the nonlinear feedback of the axion emission is an essential factor to predict the axion detectability, and underscores the need for systematic simulation studies across various progenitor models.

    ↳ astro-ph.HEastro-ph.COhep-phJCAP(2025)·3 citations
25. 25*

    Contribution of Subthreshold States to the Residual Energy Distribution of ${}^{159}$Dy

    Tadafumi Kishimoto🇯🇵 · Toru Sato🇯🇵

    We investigate the residual energy distribution in the electron capture (EC) process of ${}^{159}$Dy, emphasizing the role of subthreshold atomic states, which have typically been omitted in conventional spectral analyses. By incorporating these energetically forbidden hole states into the spectral function $P(E)$, we demonstrate a significant enhancement - over an order of magnitude - in the EC rate near the zero-momentum neutrino emission region. This enhancement increases further with larger $Q$ values, contrary to standard expectations. Our analysis shows that $P(E)$ can be experimentally determined, resolving ambiguities near the endpoint and enabling new approaches to 'ultra-low $Q$ value' EC reactions for neutrino mass studies.

    ↳ nucl-thhep-phnucl-exPRL(2025)·1 citation
26. 26*

    Kolmogorov-type non-thermal fixed points and beyond of far-from-equilibrium dilute system: ultra-cold Fermi gas

    Chun-Wei Su🇺🇸

    The far-from-equilibrium dynamics driven by the scattering from next-to-leading-order (NLO) corrections in the quantum field theory has stationary solutions for the particle distribution characterized as the Kolmogorov-type non-thermal fixed points. The dynamics of the spatially homogeneous, isotropic dilute ultra-cold Fermi gas is investigated, and its kinetic equation confirms the Kolmogorov-type non-thermal fixed points in the perturbation theory by the quasi-particle assumption, in contrast to the wave turbulence of the weakly coupled ultra-cold Bose gas. In addition, other stationary states are found without the quasi-particle assumption and in a strongly coupled system. These analytical solutions provide chances for future experiments and numerical simulations in search of far-from-equilibrium stationary states of the dilute system.

    ↳ cond-mat.quant-gascond-mat.otherhep-ph0 citations
27. 27*

    Baselines for Abelian Charge Fluctuations in Nuclear Collisions:Theory and Comparison with Experimental Data

    Bengt Friman🇩🇪 · Krzysztof Redlich🇵🇱 · Anar Rustamov🇩🇪

    We investigate fluctuations in the canonical ensemble of an Abelian charge, such as baryon number. Our focus is on cumulants and factorial cumulants of baryon and antibaryon multiplicity distributions, including their sum and difference, in both the full phase space and subsystems. In particular, we establish a correlation between net-baryon number fluctuations within a subsystem, which is pertinent for fluctuation analyses in nucleus-nucleus collisions, and fluctuations of baryon and antibaryon numbers in the total system. We derive analytical expressions for factorial cumulants of arbitrary order and present concise results in terms of the cumulants of the total baryon number. To account for dynamics beyond global conservation, we introduce local attractive and repulsive multi-particle interactions within a phenomenological framework. A comparison of calculated and generated cumulants with STAR and HADES data indicates that multiparticle interactions play a decisive role in the description of observed fluctuation patterns. At high collision energies, the data are well-reproduced by incorporating repulsive two-proton interactions, while at lower energies, attractive three-particle interactions become essential. Furthermore, our framework facilitates realistic event generation, enabling a direct comparison with experimental measurements.

    ↳ nucl-thhep-exhep-phnucl-exJHEP(2026)·11 citations
28. 28*

    SN2023syz and SN2025cbj: Two Type IIn Supernovae Associated with IceCube High-energy Neutrinos

    Ming-Xuan Lu🇨🇳 · Yun-Feng Liang🇨🇳 · Xiang-Gao Wang🇨🇳 · Hao-Qiang Zhang🇨🇳

    Type IIn supernovae (SNe IIn) are a subclass of core-collapse SNe in which strong interactions occur between the ejecta and dense circumstellar material, creating ideal conditions for the production of high-energy neutrinos. This makes them promising candidate sources of neutrinos. In this work, we conduct an association study between 163 SNe IIn observed by the Zwicky Transient Facility and 138 neutrino alert events detected by the IceCube neutrino observatory. After excluding alerts with poor localization, we find two SNe that are spatiotemporally coincident with neutrino events. IC231027A and IC250421A coincide with the positions of SN2023syz and SN2025cbj, respectively, within their localization uncertainties, and the neutrino arrival times are delayed by 38 days and 61 days relative to the discovery times of the corresponding SNe. Using Monte Carlo simulations, we estimate that the probability of such two coincidences occurring by chance in our sample is $p\sim 0.67\%$, suggesting that they may originate from genuine physical associations, though the result is not yet statistically significant. Our model calculations, however, indicate that the likelihood of a neutrino originating from IC231027A is low, implying that the association between IC231027A and SN2023syz is likely coincidental. Nevertheless, under optimistic parameters, the probability of detecting a neutrino from the whole SNe IIn sample could reach $\gtrsim 6\%$, indicating that detecting neutrino emission from the SNe population may be possible. Our study provides a systematic analysis, combining statistical analysis and model calculations, to assess whether interacting supernovae can serve as potential sources of neutrino emission.

    ↳ astro-ph.HEhep-phApJ(2026)·8 citations
29. 29*

    Quintessential dark energy crossing the phantom divide

    Ruiqi Chen🇨🇳 · James M. Cline🇨🇦 · Varun Muralidharan🇨🇦 · Benjamin Salewicz🇨🇦

    Motivated by recent results from the DESI collaboration, we explore two classes of quintessence models that can give rise to crossing of the dark energy equation of state through the ``phantom divide'' $w=-1$. These are models with Lagrangians that involve higher powers of the kinetic energy ${\dot{\varphi }}^2$, or where the dark matter (DM) mass is a function of $\varphi$. Both have similar features with respect to the reconstructed redshift-dependent $w(z)$: moderate tuning of parameters is required to achieve the desired shape, and it is difficult or impossible for $w(z)$ to continue evolving smoothly as $z$ becomes large. Nevertheless, they give a strong improvement over $\Lambda$CDM in fitting the data. We point out that models of coupled dark matter and dark energy that cross the phantom divide are under pressure from constraints on long-range DM forces. They rule out the simplest renormalizable coupling of scalar DM to quintessence, but leave the fermionic case marginally allowed, while exponentially coupled models are safe from current constraints.

    ↳ astro-ph.COhep-phJCAP(2026)·35 citations
30. 30*

    The Magnetic Origin of Primordial Black Holes: A Viable Dark Matter Scenario

    Subhasis Maiti🇮🇳 · Debaprasad Maity🇮🇳

    Primordial Black Holes (PBHs) are compelling candidates for explaining the present-day relic abundance of cold dark matter (CDM), yet their formation typically requires finely tuned early-universe dynamics. In this work, we propose a novel PBH formation mechanism within a well-established magnetogenesis framework. This scenario simultaneously accounts for the large-scale magnetic fields observed today and generates an enhanced curvature power spectrum at intermediate scales, leading to PBH formation with masses that can survive until the present epoch. We identify a narrow reheating temperature range, $10^5\mathrm{GeV}\le T_{re}\le 3\times 10^5\mathrm{GeV}$, within which the resulting PBHs can constitute the entirety of the observed CDM abundance. Furthermore, our model predicts a stochastic gravitational wave (GW) background as a byproduct of the PBH formation process. Remarkably, the predicted GW signal lies within the sensitivity reach of upcoming space-based interferometers, such as the LISA, DECIGO, or SKA mission, offering a direct observational probe of this PBH generation mechanism.

    ↳ astro-ph.COhep-phJCAP(2026)·8 citations
31. 31*

    Quantifying fluctuation signatures of the QCD critical point using maximum entropy freeze-out

    Jamie M. Karthein🇺🇸 · Maneesha Sushama Pradeep🇺🇸 · Krishna Rajagopal🇺🇸 · Mikhail Stephanov🇺🇸 · Yi Yin🇨🇳

    A key question about the QCD phase diagram is whether there is a critical point somewhere on the boundary between the hadronic and quark-gluon plasma phases, and if so where. Heavy-ion collisions offer a unique opportunity to search for signatures of such a critical point by analyzing event-by-event fluctuations in particle multiplicities. To draw meaningful conclusions from experimental data, a theoretical framework is needed to link QCD thermodynamics with the particle spectra and correlations observed in detectors. The Equation of State (EoS) of QCD near a critical point can be related to the universal Gibbs free energy of the 3D Ising model using four currently unknown non-universal mapping parameters whose values are determined by the microscopic details of QCD. We utilize the maximum entropy approach to freeze-out the fluctuations in order to make estimates for factorial cumulants of proton multiplicities, assuming thermal equilibrium, for a family of EoS with a 3D Ising-like critical point, varying the microscopic inputs that determine the strength and structure of the critical features. We quantify the effect of the non-universal mapping parameters, and the distance between the critical point and the freeze-out curve, on the factorial cumulants of proton multiplicities.

    ↳ nucl-thhep-phnucl-exPRD(2026)·12 citations
32. 32*

    Implications for Pulsar Timing Arrays of Sub-solar Black Hole Detections: From LVK to Einstein Telescope and Cosmic Explorer

    Yann Gouttenoire🇩🇪 · Sokratis Trifinopoulos🇨🇭 · Miguel Vanvlasselaer🇧🇪

    The detection of compact binary mergers with sub-solar masses at gravitational-wave observatories could mark the groundbreaking discovery of primordial black holes (PBHs). Concurrently, evidence for a nHz stochastic gravitational wave background observed by pulsar timing arrays (PTAs) could suggest a non-astrophysical origin, potentially arising from scalar-induced gravitational waves (SIGW). In this work, we analyze the connection between the two phenomena in the case where they share a common origin: the collapse of large primordial curvature perturbations in the early universe. We focus on sub-solar PBH populations within reach of upcoming experiments, including the current and future runs of LIGO-Virgo-KAGRA as well as the third generation observatories such as the Einstein Telescope and Cosmic Explorer. Using a Bayesian framework with physically motivated priors, we perform a consistent model comparison that incorporates existing astrophysical bounds together with the discovery potential of future detectors. Our analysis lends stronger support for the SIGW interpretation over the astrophysical one, as the narrowed priors place greater weight on the region of highest likelihood. Ultimately, we illustrate that combining PTA data with interferometer searches can deliver correlated evidence for new physics across multiple gravitational-wave bands.

    ↳ astro-ph.COhep-phJCAP(2026)·12 citations
33. 33*

    Lensing by black holes within astrophysical environments

    Gerasimos Kouniatalis · Arthur G. Suvorov🇪🇸 · Kyriakos Destounis🇵🇹

    Astrophysical black holes are likely to be surrounded by various forms of matter in the form of disks or halos. While a number of studies have examined the impact of an environment on the lensing of light or gravitational waves from cosmological sources, these have, thus far, been carried out in either a Newtonian or post-Newtonian framework where the environment is superimposed on the black-hole spacetime. By using an exact solution in general relativity describing a black hole embedded within a realistic halo of Hernquist matter distribution, we study deflection angles and image amplification in a fully relativistic setup. It is shown that large ``bumps'', that also arise at the Newtonian and post-Newtonian levels, track the transition scale set by the halo parameters that control the strong-lensing upturn and can significantly adjust the inferences made for either the source or lens in various contexts. As an application, we consider ``echoes'' of gravitational waves, sourced by astrophysical lenses rather than being intrinsic to the compact object that produces the signal.

    ↳ gr-qcastro-ph.GAastro-ph.HEhep-phPRD(2025)·14 citations
34. 34*

    GammaPBHPlotter: A public code for calculating the complete Hawking evaporation gamma-ray spectra from primordial black holes

    John Carlini🇺🇸 · Ilias Cholis🇺🇸

    We present GammaPBHPlotter, a public Python code for calculating and plotting the Hawking radiation gamma-ray spectra of primordial black holes in the mass range of $10^{14}$ to $10^{18}$ grams. This tool allows users to compute the monochromatic and mass-averaged spectra of black holes over a range of parameters. We include the primary/direct Hawking emission, the secondary emission from the decay and hadronization of unstable particles, the final state radiation, and the in-flight annihilation gamma-ray emission components.

    ↳ astro-ph.HEastro-ph.COastro-ph.IMgr-qc+11 citation
35. 35*

    Finite-volume analysis and universal scaling signatures near the chiral phase transition in (2+1)-flavor QCD

    Sabarnya Mitra🇩🇪 · Frithjof Karsch🇩🇪

    For quantifying the universal properties of the chiral phase transition in QCD through numerical calculations on a discrete space-time lattice, one needs to perform controlled extrapolations to the continuum and infinite-volume limits followed by an extrapolation to the limit of massless light quarks. We discuss here, the results on the latter two limits at still finite lattice spacings. We use here for chiral symmetry breaking, an improved order parameter free of additive and multiplicative divergences and we analyse its volume and quark mass dependence. Comparing to the expected universal behavior in the chiral limit, we quantify deviations from the universal finite-size scaling behavior as function of the light to strange quark mass ratio.

    ↳ hep-lathep-phhep-thnucl-ex+1EPJ Web Conf.(2026)·3 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.