Fri·Apr 4, 2025Friday·April 4, 2025

1. 01*

   Indications for freeze-out of charge fluctuations in the quark-gluon plasma at the LHC

   Jonathan Parra🇺🇸 · Roman Poberezhniuk🇺🇦 · Volker Koch🇺🇸 · Claudia Ratti🇺🇸 · Volodymyr Vovchenko🇺🇸

   The D-measure of net-charge fluctuations quantifies the variance of net charge in strongly interacting matter. It was introduced over 20 years ago as a potential signal of quark-gluon plasma (QGP) in heavy-ion collisions, where it is expected to be suppressed due to the fractional electric charges of quarks. Measurements have been performed at RHIC and LHC, but the conclusion has been elusive in the absence of quantitative calculations for both scenarios. We address this issue by employing a recently developed formalism of density correlations and incorporate resonance decays, local charge conservation, and experimental kinematic cuts. We find that the hadron gas scenario is in fair agreement with the ALICE data for $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV Pb-Pb collisions only when a very short rapidity range of local charge conservation is enforced, while the QGP scenario is in excellent agreement with experimental data and largely insensitive to the range of local charge conservation. A Bayesian analysis of the data utilizing different priors yields moderate evidence for the freeze-out of charge fluctuations in the QGP phase relative to hadron gas. The upcoming high-fidelity measurements from LHC Run 2 will serve as a precision test of the two scenarios.

   hep-phnucl-exnucl-thPRL(2025)·8 citations
2. 02*

   Quark mass matrices inspired by a numerical relation

   A. C. Kleppe🇳🇴

   In 1981, Yoshio Koide noticed that the square root values of the charged lepton masses satisfy the relation \[ Q=\frac{m_e+m_{\mu}+m_{\tau}}{(\sqrt{m_e}+\sqrt{m_{\mu}}+\sqrt{m_{\tau}})^2} \approx \frac{2}{3} \] Inspired by this relation, we introduce tentative mass matrices, using numerical values, and find matrices that display an underlying democratic texture.

   hep-phProceedings to the 27th workshop What Com…·1 citation
3. 03*

   F-Term Hybrid Inflation and SUSY Breaking

   C. Pallis🇬🇷

   We consider F-term hybrid inflation and supersymmetry breaking in the context of a model which largely respects a global U(1) R symmetry. The Kaehler potential parameterizes the Kaehler manifold with an enhanced U(1)_Rx(SU(1,1)/U(1)) symmetry, where the scalar curvature of the second factor is determined by the achievement of a supersymmetry-breaking de Sitter vacuum without ugly tuning. The magnitude of the emergent soft tadpole term for the inflaton can be adjusted in the range (1.2-460) TeV -- increasing with the dimensionality of the representation of the waterfall fields -- so that the inflationary observables are in agreement with the observational requirements. The mass scale of the supersymmetric partners turns out to lie in the region (0.09-253) PeV which is compatible with high-scale supersymmetry and the results of LHC on the Higgs boson mass. The mu parameter can be generated by conveniently applying the Giudice-Masiero mechanism and assures the out-of-equilibrium decay of the R saxion at a low reheat temperature Trh<163 GeV.

   hep-phastro-ph.COhep-thPoS(2025)·1 citation
4. 04*

   Nonperturbative heavy quark diffusion coefficients in a weakly magnetized thermal QCD medium

   Debarshi Dey🇮🇳 · Aritra Bandyopadhyay🇷🇴 · Santosh K. Das🇮🇳 · Sadhana Dash🇮🇳 · Vinod Chandra🇮🇳 · Basanta K. Nandi🇮🇳

   In this work, the perturbative and non-perturbative contributions to the heavy quark (HQ) momentum ($\kappa$) as well as spatial ($D_s$) diffusion coefficients are computed in a weak background magnetic field. The formalism adopted here involves calculation of the in-medium potential of the HQ in a weak magnetic field, which then serves as a proxy for the resummed gluon propagator in the calculation of HQ self-energy ($\Sigma$). The self-energy determines the scattering rate of HQs with light thermal partons, which is subsequently used to evaluate $\kappa$ and $D_s$. It is observed that non-perturbative effects play a dominant role at low temperature. The spatial diffusion coefficient $2\pi T{D}_s$, exhibits good agreement with recent LQCD results. These findings can be applied to calculate the heavy quark directed flow at RHIC and LHC energies. An extension of this formalism to the case of finite HQ momentum has also been attempted.

   hep-phnucl-thPRD(2025)·5 citations
5. 05*

   Measuring the Low-Energy Weak Mixing Angle with Supernova Neutrinos

   Chun-Ming Yip🇨🇳 · Xu-Run Huang🇨🇳 · Ming-chung Chu🇨🇳 · Qishan Liu🇨🇳

   The weak mixing angle ${\theta }_W$ is a fundamental parameter in the electroweak theory with a value running according to the energy scale, and its precision measurement in the low-energy regime is still ongoing. We propose a method to measure the low-energy $\sin {}^2{\theta }_W$ by taking advantage of Argo, a future ton-scale liquid argon dark matter detector, and the neutrino flux from a nearby core-collapse supernova (CCSN). We evaluate the expected precision of this measurement through the coherent elastic neutrino-nucleus scattering (CE$\nu$NS) channel. We show that Argo is potentially capable of achieving a few percent determination of $\sin {}^2{\theta }_W$, at the momentum transfer of $q\sim 20$ MeV, in the observation of a CCSN within $\sim 3$ kpc from the Earth. Such a measurement is valuable for both the precision test of the electroweak theory and searching for new physics beyond the standard model in the neutrino sector.

   hep-phEPJC(2025)·1 citation
6. 06*

   ToMCCA-3: A realistic 3-body coalescence model

   Maximilian Mahlein🇩🇪 · Bhawani Singh🇩🇪 · Michele Viviani🇮🇹 · Francesca Bellini🇮🇹 · Laura Fabbietti🇩🇪 · Alejandro Kievsky🇮🇹 · Laura Elisa Marcucci🇮🇹

   The formation of light nuclei in high-energy collisions provides valuable insights into the underlying dynamics of the strong interaction and the structure of the particle-emitting source. Understanding this process is crucial not only for nuclear physics but also for astrophysical studies, where the production of rare antinuclei could serve as a probe for new physics. This work presents a three-body coalescence model based on the Wigner function formalism, offering a refined description of light-nucleus production. By incorporating realistic two- and three-body nuclear interaction potentials constrained by modern scattering and femtoscopic correlation data, our approach improves on traditional coalescence models. The framework is validated using event generators applied to proton-proton collisions at $\sqrt{s}=13$ TeV to predict the momentum spectra of light (anti) nuclear nuclei with mass number $A=3$, which are then compared with the experimental data from ALICE. Our results demonstrate the sensitivity of light nucleus yields to the choice of nuclear wave functions, emphasizing the importance of an accurate description of the coalescence process. This model lays the foundation for the extension of coalescence studies of $A=3$ light nuclei to a wider range of collision systems and energies.

   hep-phnucl-th6 citations
7. 07*

   Effective field theory for type II seesaw model --symmetric phase v.s. broken phase--

   Yi Liao🇨🇳 · Xiao-Dong Ma🇨🇳 · Yoshiki Uchida🇨🇳

   Effective field theory is an effective approach to parameterizing effects of high energy scale physics in low energy measurements. The two popular frameworks for physics beyond the standard model are the so-called standard model effective field theory (SMEFT) and the Higgs effective field theory (HEFT). While the description by the SMEFT deteriorates when the scale of new physics is not so high or it participates in spontaneous electroweak symmetry breaking, the HEFT makes use of nonlinear realization of spontaneously broken symmetry in which there are practically no restrictions on the Higgs field as a singlet. In this work we present another framework, called broken phase effective field theory (bEFT), in which we deal directly with mass eigenstate fields after spontaneous symmetry breaking without employing nonlinear realization. We take the type-II seesaw model as an example to demonstrate our approach. By matching the model to both the bEFT and the SMEFT at tree level, we compare the results for two processes, the Higgs pair production via vector boson fusion which appears as a subprocess at the LHC and the Higgs-strahlung process at a future electron-positron collider. We find that the bEFT reproduces the type-II seesaw model more accurately than the SMEFT in the regions where the bare mass of the Higgs triplet becomes close to the electroweak scale. Therefore, the bEFT serves as a useful framework that can compensate for the shortcomings in both the SMEFT and the HEFT when dealing with UV models that involve Higgs mixing or new particles with a mass close to the electroweak scale.

   hep-phPRD(2025)·2 citations
8. 08*

   Input to the European Strategy for Particle Physics: Strong-Field Quantum Electrodynamics

   G. Sarri🇬🇧 · B. King🇬🇧 · T. Blackburn🇸🇪 · A. Ilderton🇬🇧 · S. Boogert🇬🇧 · S.S. Bulanov🇺🇸 · S.V. Bulanov🇷🇴 · A. Di Piazza🇺🇸 · L. Ji🇨🇳 · F. Karbstein🇩🇪 · C. H. Keitel🇩🇪 · K. Krajewska🇵🇱 and 12 other authors

   This document sets out the intention of the strong-field QED community to carry out, both experimentally and numerically, high-statistics parametric studies of quantum electrodynamics in the non-perturbative regime, at fields approaching and exceeding the critical or `Schwinger' field of QED. In this regime, several exotic and fascinating phenomena are predicted to occur that have never been directly observed in the laboratory. These include Breit-Wheeler pair production, vacuum birefringence, and quantum radiation reaction. This experimental program will also serve as a stepping stone towards studies of elusive phenomena such as elastic scattering of real photons and the conjectured perturbative breakdown of QED at extreme fields. State-of-the-art high-power laser facilities in Europe and beyond are starting to offer unique opportunities to study this uncharted regime at the intensity frontier, which is highly relevant also for the design of future multi-TeV lepton colliders. However, a transition from qualitative observational experiments to quantitative and high-statistics measurements can only be performed with large-scale collaborations and with systematic experimental programs devoted to the optimisation of several aspects of these complex experiments, including detector developments, stability and tolerances studies, and laser technology.

   hep-phEur.Phys.J.Plus(2025)·19 citations
9. 09*

   Backward DVCS in a Sullivan process

   Abigail R. Castro🇫🇷 · Cédric Mezrag🇫🇷 · Jose M. Morgado Chávez🇫🇷 · Bernard Pire🇫🇷

   Mesons' internal structure and dynamics may be accessed through hard exclusive electroproduction processes such as deeply virtual Compton scattering in both near forward and near backward kinematics. With the help of the Sullivan process which allows us to use a nucleon target as a quasi-real $\pi$ meson emitter, we study backward scattering in the framework of collinear QCD factorization where pion-to-photon transition distribution amplitudes describe the photon content of the $\pi$ meson. We present a model of these TDAs based on the overlap of lightfront wave functions primarily developed for generalized parton distributions, using a previously developed pion lightfront wave function and deriving a new model for the lightfront wave functions of the photon. This leads us to an estimate of the cross-sections for JLab energies. We conclude that deeply virtual $ep\to e\gamma Mn$ processes, in backward kinematics, may be experimentally discovered in the near future.

   hep-phnucl-thPRD(2025)·8 citations
10. 10*

    Background-Enhanced Axion Force by Axion Dark Matter

    Yu Cheng🇰🇷 · Shuailiang Ge🇰🇷

    We investigate the influence of axion dark matter as a background on the spin-independent axion forces between nucleons. Notably, we find that the potential for axion forces scales from $1/r^3$ in a vacuum-only context to $1/r$ when the background effect is considered. Also, the magnitude of the axion force is substantially amplified in proportion to the number density of axion DM particles. These enhancements significantly improve the constraints on the axion decay constant by several orders of magnitude, across a broad range of axion masses, based on the fifth-force experiments such as the Casimir-less and torsion balance tests. This suggests that such experiments are more effective than previously understood in detecting axions.

    hep-phPRD(2026)·12 citations
11. 11*

    Complex heavy-quarkonium potential in an anisotropic collisional quark-gluon plasma

    Manas Debnath🇮🇳 · Lata Thakur🇰🇷 · Najmul Haque🇮🇳

    We compute the complex heavy-quark potential in an anisotropic quark-gluon plasma (QGP) using kinetic theory with a Bhatnagar-Gross-Krook collision kernel. By incorporating momentum anisotropy and a finite collision rate into the medium dielectric response, we derive both the real and the imaginary parts of the in-medium potential. The real part of the inverse dielectric function is obtained from the retarded/advanced gluon propagator, while the imaginary part is determined from the Feynman (symmetric) propagator. We find that collisions have only a minimal impact on the real part of the potential, suggesting a similarly weak effect on the binding energy. In an anisotropic plasma, the Weibel instability induces a pinch singularity that can render the imaginary part of the potential ill-defined; we show that sufficiently large collision rates regularize this singularity, yielding a well-defined imaginary potential in the corresponding region of parameter space. In this well-defined regime, collisions significantly enhance the magnitude of the imaginary part and modify the effect of anisotropy. This enhancement leads to larger quarkonium thermal widths and dissociation rates in a nonequilibrium QGP, providing further insight into quarkonium suppression mechanisms.

    hep-phPRD(2026)·3 citations
12. 12*

    Excitation of the Glashow resonance without neutrino beams

    I. Alikhanov🇷🇺

    The $s$-channel process ${\bar{\nu }}_e{e}^{-}\to W^{-}$ (on-shell) is now referred to as the Glashow resonance and being searched for at kilometer-scale neutrino ice/water detectors like IceCube, Baikal-GVD or KM3NeT. After over a decade of observations, IceCube has recorded only a few neutrino events with energies of interest such that an independent confirmation of the existence of this resonant interaction would be of great importance for testing the Standard Model. One might therefore ask: are there reactions with the Glashow resonance that would not necessitate having initial (anti)neutrino beams? This article suggests a surprisingly affirmative answer to the question $-$ namely, that the process may proceed in electron-positron collisions at accelerator energies, occurring as $e^{+}{e}^{-}\to W^{-}\rho (770{)}^{+}$. Although the resonance appears somewhat disguised, the underlying physics is transparent, quite resembling the well known radiative return: emission of ${\rho }^{+}$ from the initial state converts the incident $e^{+}$ into ${\bar{\nu }}_e$. Likewise, the CP conjugate channel, ${\nu }_e{e}^{+}\to W^{+}$, takes the form $e^{+}{e}^{-}\to W^{+}\rho (770{)}^{-}$. Similar reactions with muons and other hadrons are also possible. From this viewpoint, future high-luminosity lepton colliders seem to be promising for excitation of the Glashow resonance in laboratory conditions.

    hep-ph1 citation
13. 13*

    Determining Spin-Dependent Light Dark Matter Rates from Neutron Scattering

    Asher Berlin🇺🇸 · Alexander J. Millar🇺🇸 · Tanner Trickle🇺🇸 · Kevin Zhou🇺🇸

    The scattering and absorption rates of light dark matter with electron spin-dependent interactions depend on the target's spin response. We show how this response is encoded by the target's dynamical magnetic susceptibility, which can be measured using neutron scattering. We directly use existing neutron scattering data to compute the dark matter scattering rate in a candidate target material, finding close agreement with the previous first-principles calculation at MeV dark matter masses. Complementary experiments and measurements can extend the reach of this technique to other dark matter models and masses, and identify promising target materials for future experiments.

    hep-phastro-ph.COcond-mat.mtrl-scicond-mat.str-el+1PRD(2025)·8 citations
14. 14*

    Visible Collider Signals of Natural Quirks

    Joshua Forsyth🇺🇸 · Matthew Low🇺🇸 · Carson Tenney🇺🇸 · Christopher B. Verhaaren🇺🇸

    Though some LHC searches for new physics exceed the TeV scale, there may be discoveries waiting to be made at much lower masses. We outline a simple quirk model, motivated by models that address the hierarchy problem through neutral naturalness, in which new electroweakly charged states with masses as low as 100 GeV have not yet been probed by the LHC. We also describe a novel search strategy which is complementary to current search methods. In particular, we show its potential to discover natural quirks over regions of parameter space that present methods will leave unexplored, even after the LHC's high-luminosity run.

    hep-phhep-exPRD(2025)·7 citations
15. 15*

    Near-Peak Spectrum of Gravitational Waves from Collapsing Domain Walls

    Bryce Cyr🇺🇸 · Steven Cotterill🇬🇧 · Richard Battye🇬🇧

    Cosmological domain walls appear in many well-motivated extensions to the standard model of particle physics. If produced, they quickly enter into a self-similar scaling regime, where they are capable of efficiently sourcing a stochastic background of gravitational waves. In order to avoid a cosmological catastrophe, they must also decay before their enormous energy densities can have adverse effects on background dynamics. Here, we provide a suite of lattice simulations to comprehensively study the gravitational wave signatures of the domain wall network during this decay phase. The domain walls are initially formed through spontaneous breaking of a ${\mathbb{Z}}_2$ symmetry, and subsequently decay through the action of a small bias term which causes regions of false vacuum to collapse. We find that gravitational waves are produced in abundance throughout this collapsing phase, leading to a shift in the peak frequency and increase in the overall amplitude of the spectrum by an $\mathcal{O}(100)$ factor when compared against simple analytic arguments. Importantly, we also find that the characteristic frequency of emitted gravitational waves increases as the network decays, which leads to a softening of the high frequency spectral index. This high frequency spectrum therefore carries key information related to the dynamics of the collapsing phase, and can be used to discriminate between different domain wall scenarios using upcoming data.

    ↳ astro-ph.COgr-qchep-phPRD(2026)·22 citations
16. 16*

    Isospin kaon anomaly and its consequences

    Francesco Giacosa🇵🇱 · Martin Rohrmoser🇵🇱

    Isospin symmetry is well fulfilled in the QCD vacuum, as evidenced by small mass differences of isospin partners and suppressed isospin-violating decays. Recently, the NA61/SHINE collaboration reported an unexpectedly large isospin-violating charged-to-neutral kaon ratio in Ar-Sc heavy-ion collisions (HIC).Using a quark recombination approach, we introduce a function of kaon multiplicities that reduces to unity in the isospin-symmetric limit independently of the scattering energy and type of nuclei. Using this quantity, we show that nucleus-nucleus collisions violate isospin sizably (at the $6.4\sigma$--level), while proton-proton data on kaon multiplicities do not. We predict other isospin-violating enhancements in HIC, such as the proton-to-neutron ratio $p/n\sim 1.2$ and the hyperon ratio ${\Sigma }^{+}/{\Sigma }^{-}\sim 1.4$. Finally, we extend the approach to antiquarks in the initial state, useful for e.g. pion-nucleus scattering reactions.

    ↳ nucl-thhep-phnucl-exEPJC(2025)·2 citations
17. 17*

    The temperature dependence of fractional topological charge objects

    Jackson A. Mickley🇦🇺 · Waseem Kamleh🇦🇺 · Derek B. Leinweber🇦🇺

    We present a novel method for defining the topological charge contained within distinct topological objects in the nontrivial ground-state fields of SU(N) lattice gauge theory. Such an analysis has been called for by the growing number of models for Yang-Mills topological structure which propose the existence of fractionally charged objects. This investigation is performed for SU(3) at a range of temperatures across the deconfinement phase transition, providing an assessment of how the topological structure evolves with temperature. This reveals a connection between the topological charge and holonomy of the system which must be satisfied by finite-temperature models of Yang-Mills vacuum structure. We find a promising consistency with the instanton-dyon model for SU(N) vacuum structure.

    ↳ hep-lathep-phnucl-thPoS(2025)·2 citations
18. 18*

    Diversifying halo structures in two-component self-interacting dark matter models via mass segregation

    Daneng Yang🇺🇸 · Yue-Lin Sming Tsai🇨🇳 · Yi-Zhong Fan🇨🇳

    Self-interacting dark matter (SIDM), through gravothermal evolution driven by elastic self-scatterings, offers a compelling explanation for the observed diversity of inner halo densities. In this work, we investigate SIDM dynamics in a two-component dark matter model with mass ratios of order unity, motivated by an asymmetric dark matter framework that naturally evades constraints from relic abundance and mediator decay, while enabling strong, velocity-dependent self-interactions. We show that cross-component scatterings significantly enhance mass segregation, driving the formation of dense, core collapsed-like halos. This effect couples naturally to SIDM-induced diversity, introducing a new mechanism for generating structural variations beyond those arising from gravothermal evolution alone. Our results reveal a novel mechanism for reconciling SIDM with small-scale observational tensions by enabling shifts in central densities while preserving the flexibility to generate diverse halo structures. We further highlight that halo structural diversity may serve as a diagnostic of dark sector composition, opening a new observational window into the particle nature of SIDM.

    ↳ astro-ph.COhep-phPRD(2025)·15 citations
19. 19*

    Quantization of massive fermions in vacuum and external fields

    Maxim Dvornikov (IZMIRAN)🇷🇺

    We study massive Majorana neutrinos in background matter. Representing these particles in terms of Weyl spinors, we carry out their quantization. The propagators of these fields are also constructed. Then, we apply the Hamilton dynamics based formalism to describe massive Majorana neutrinos in matter on the classical level. Finally, we study a classical Dirac particle in vacuum, described with $c$-number variables, within the Hamiton formalism. Such a Dirac field is also canonically quantized.

    ↳ hep-thhep-phPhys.Atom.Nucl.(2026)·1 citation
20. 20*

    Heavy meson lightcone distribution amplitudes from Lattice QCD

    Xue-Ying Han · Jun Hua · Cai-Dian Lü · Andreas Schäfer · Yushan Su · Wei Wang · Ji Xu · Yibo Yang · Jian-Hui Zhang · Qi-An Zhang · Shuai Zhao

    Lightcone distribution amplitudes (LCDAs) within the framework of heavy quark effective theory (HQET) play a crucial role in the theoretical description of weak decays of heavy bottom mesons. However, the first-principle determination of HQET LCDAs faces significant theoretical challenges. In this presentation, we introduce a practical approach to address these obstacles. This makes sequential use of effective field theories. Leveraging the newly-generated lattice ensembles, we present a pioneering lattice calculation, offering new insights into LCDAs for heavy mesons. Additionally, we discuss the impact of these results on the heavy-to-light form factors and briefly give potential future directions in this field.

    ↳ hep-lathep-exhep-phPoS(2025)·5 citations
21. 21*

    Gravitational Wave with Domain Wall Dominance

    Sungwoo Hong🇰🇷 · Sung Mook Lee🇨🇭 · Qiuyue Liang🇯🇵

    Domain walls (DWs) can be produced when a discrete symmetry is spontaneously broken, and long-lived DWs can dominate the energy density of the universe. In this work, we explore the possibility that a "domain wall dominant (DWD)" phase existed in the early universe and ended with DW decay. During the DWD phase, the universe undergoes a power-law accelerated expansion of the scale factor and exhibits temporal superhorizon evolution of the relevant frequency modes. We show that this can lead to distinct features imprinted on the stochastic gravitational wave (GW) background including the independence of its amplitude from the wall tension. Our findings provide a comprehensive framework for evaluating GW emission associated with DWD, leading to distinguishable long-lived DW-induced GWs from other cosmological sources, with significant implications for future GW observatories.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2026)·4 citations
22. 22*

    Globular cluster distributions as a dynamical probe of dark matter

    Nativ Ben-Yeda · Kfir Blum🇮🇱 · Inbar Havilio

    Globular clusters (GCs) act as massive probe particles traversing the dark matter halos of their host galaxies. Gravitational dynamical friction due to halo particles causes GC orbits to contract over time, providing a beyond-mean field test of the cold dark matter paradigm. We explore the information content of such systems, using N-body and semianalytic simulations and scanning over a range of initial conditions. We consider data from the ultradiffuse galaxies NGC5846-UDG1 and UDG-DF44, and from the Fornax dwarf spheroidal galaxy. The GC systems of UDG1 and Fornax indicate the presence of dark matter halos, independent of (but consistent with) stellar kinematics data. UDG-DF44 is too diffuse for dynamical friction to give strong constraints. Our analysis can be extended to many additional galaxies.

    ↳ astro-ph.GAhep-phApJ(2026)·0 citations
23. 23*

    Revealing the harmonic structure of nuclear two-body correlations in high-energy heavy-ion collisions

    Thomas Duguet🇫🇷 · Giuliano Giacalone🇨🇭 · Sangyong Jeon🇨🇦 · Alexander Tichai🇩🇪

    Smashing nuclei at ultrarelativistic speeds and analyzing the momentum distribution of outgoing debris provides a powerful method to probe the many-body properties of the incoming nuclear ground states. Within a perturbative description of initial-state fluctuations in the quark-gluon plasma, we express the measurement of anisotropic flow in ultra-central heavy-ion collisions as the quantum-mechanical average of a specific set of operators measuring the harmonic structure of the two-body azimuthal correlations among nucleons in the colliding states. These observables shed a new light on spatial correlations in atomic nuclei, while enabling us to test the complementary pictures of nuclear structure delivered by low- and high-energy experiments on the basis of state-of-the-art theoretical approaches rooted in quantum chromodynamics.

    ↳ nucl-thhep-exhep-phnucl-exPRL(2025)·24 citations
24. 24*

    Rapidity spectra in high-energy collisions and longitudinal nuclear suppression from nonadditive statistics

    Trambak Bhattacharyya🇵🇱 · Maciej Rybczyński🇵🇱 · Zbigniew Włodarczyk🇵🇱

    We investigate the longitudinal nuclear suppression factor defined by a scaled ratio of rapidity distributions. To study this experimental observable, we describe three approaches involving numerical and analytical calculations. We first approach this problem by conducting model studies using EPOS, FTFP${}_{BERT}$, and HIJING, and notice that while EPOS shows a decreasing trend of this ratio at forward/backward rapidities, the latter two model calculations display an increment of the ratio. The analytical approaches involve, first, the quasi-exponential distribution obtained from the Tsallis statistics, and second, the nonadditive Boltzmann transport equation in the relaxation time approximation. We notice that our analytical results satisfactorily describe NA61 experimental data (for $\sqrt{s_{NN}}$=6.3, 7.6, 8.8, 12.3, and 17.3 GeV) for the negatively charged pions.

    ↳ nucl-thhep-exhep-phnucl-exPLB(2026)·1 citation
25. 25*

    Unveiling the reflection spectrum in the ultracompact LMXB 4U 1820-30

    A. Anitra · A. Gnarini · T. Di Salvo · R. Iaria · A. Sanna🇮🇹 · L. Burderi · A. Marino🇺🇸 · M. Del Santo · G. Matt · F. Ursini · S. Bianchi · F. Capitanio and 3 other authors

    4U 1820-30 is a ultracompact X-ray binary located in the globular cluster NGC 6624, consisting of a neutron star accreting material from a helium white dwarf companion characterized by the shortest known orbital period for this type of star (11.4 minutes). Despite extensive studies, the detection of the relativistic Fe K emission line, has been inconsistently reported and no measurement of the system inclination has been achieved. In this work, we investigate the broadband spectral and polarimetric properties of 4U 1820-30, exploring the presence of a reflection component and its role in shaping the polarization signal. We analyzed simultaneous X-ray observations from NICER, NuSTAR, and IXPE. The spectral continuum was modeled with a disk blackbody, a power law, and a Comptonization component with seed photons originating from a boundary layer. We detected a strong reflection component, described, for the first time, with two self-consistent models ({\tt Relxillns} and {\tt Rfxconv}), allowing us to provide a measurement of the system inclination angle (about 31 degrees), supporting the low-inclination hypothesis. Subsolar iron abundances were detected in the accretion disk and interstellar medium, probably related to the source location in a metal-poor globular cluster. The polarization increases from an upper limit of $1.2\%$ in the 2--4 keV band up to about $8\%$ in the 7--8 keV range. The disk is expected to be orthogonally polarized to these components, which may help to explain the decreasing of the observed polarization at low energies. However, the high polarization degree we found challenges the current models, also taking into consideration the relatively low inclination angle derived from the spectral analysis.

    ↳ astro-ph.HEhep-phAstron.Astrophys.(2025)·4 citations
26. 26*

    Constraining hot and cold nuclear matter properties from heavy-ion collisions and deep-inelastic scattering

    Anton Andronic🇩🇪 · Nicolas Borghini🇩🇪 · Xiaojian Du🇪🇸 · Christian Klein-Bösing🇩🇪 · Renata Krupczak🇩🇪 · Hendrik Roch🇺🇸 · Sören Schlichting🇩🇪

    We perform a global analysis of deep-inelastic $e+p$ scattering data from HERA and transverse energy distributions in $p+p$ and $p+\mathrm{Pb}$ collisions, alongside charged hadron multiplicities in $\mathrm{Pb}+\mathrm{Pb}$ collisions at $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$ from ALICE. Using a saturation-based initial state model grounded in high-energy QCD, we determine the early-time non-equilibrium shear viscosity to entropy density ratio $\eta /s$ of the quark-gluon plasma. Our results provide new insights into the early-time transport properties of nuclear matter under extreme conditions.

    ↳ nucl-thhep-phJHEP(2026)·5 citations
27. 27*

    Parity violation as enforced symmetry breaking in 3D fermionic topological order

    Shang-Qiang Ning🇨🇳 · Yang Qi🇨🇳 · Chenjie Wang🇨🇳 · Zheng-Cheng Gu🇨🇳

    Symmetry can be intrinsically broken in topological phases due to inherent incompatibilities, a phenomenon known as enforced symmetry breaking (ESB) in the framework of topological order. In our previous work, we developed a systematic framework to understand ESB within 2D invertible topological order. Meanwhile, the origin of parity violation in the Standard Model remains one of the most profound mysteries in physics, with no clear explanation to date. In this study, we explore the ESB of parity symmetry by three-dimensional fermionic topological order (fTO), offering potential insights into the origins of parity violation. As the simplest example, here we consider an fTO related to the intrinsic interacting fermionic SPT phase protected by $Z_2^f\times Z_2\times Z_8$ symmetry in three dimensions. We show that time-reversal symmetry (TRS) with $T^2=1$ on physical fermions is incompatible with such fTO; then, through the so-called crystalline equivalence principle, we show that the parity symmetry is also incompatible with it. In comparison, conventional TRS with $T^2=P_f$ remains compatible to this fTO. We also discuss a general framework to study the ESB phenomenon for 3D fTO.

    ↳ cond-mat.str-elcond-mat.supr-conhep-phhep-th0 citations
28. 28*

    Fractional attractors in light of the latest ACT observations

    Christian Dioguardi🇪🇪 · Antonio J. Iovino🇦🇪 · Antonio Racioppi🇪🇪

    In light of the latest results from ACT observations we review a class of potentials labeled as fractional attractors, that can originate from Palatini gravity. We show that, for certain choices of the scalar potential $V(\varphi )$, the fractional attractors predict both a spectral index $n_s$ and a tensor-to-scalar ratio $r$ that fall within the $1\sigma$ region of the combined ACT+Planck data for a wide range of parameters. We also provide a numerical fit for the parameter space of this models in the case of a simple quadratic and quartic fractional potential.

    ↳ gr-qcastro-ph.COhep-phPLB(2025)·103 citations
29. 29*

    Bubbles in a box: Eliminating edge nucleation in cold-atom simulators of vacuum decay

    Alexander C. Jenkins🇬🇧 · Hiranya V. Peiris🇬🇧 · Andrew Pontzen🇬🇧

    The decay of metastable 'false vacuum' states via bubble nucleation plays a crucial role in many cosmological scenarios. Cold-atom analog experiments will soon provide the first empirical probes of this process, with potentially far-reaching implications for early-Universe cosmology and high-energy physics. However, an inevitable difference between these analog systems and the early Universe is that the former have a boundary. We show, using a combination of Euclidean calculations and real-time lattice simulations, that these boundaries generically cause rapid bubble nucleation on the edge of the experiment, obscuring the bulk nucleation that is relevant for cosmology. We demonstrate that implementing a high-density 'trench' region at the boundary completely eliminates this problem, and recovers the desired cosmological behavior. Our findings are relevant for ongoing efforts to probe vacuum decay in the laboratory, providing a practical solution to a key experimental obstacle.

    ↳ cond-mat.quant-gasastro-ph.COgr-qchep-ph+1PRA(2025)·9 citations
30. 30*

    Supersizing hydrodynamical simulations of reionization using perturbative techniques

    Wenzer Qin🇺🇸 · Katelin Schutz🇨🇦 · Olivia Rosenstein🇺🇸 · Stephanie O'Neil🇺🇸 · Mark Vogelsberger🇺🇸

    We show that perturbative techniques inspired by effective field theory (EFT) can be used to "paint on" the 21~cm field during reionization using only the underlying linear density field. This procedure is accurate to within O(10%) on large scales and thus can be used to enlarge or "supersize" hydrodynamical simulations. In particular, the EFT provides a mapping between the linear density field and a nonlinear tracer field, both in real and redshift space. We show that this mapping can be reliably extracted from relatively small simulation volumes using the THESAN suite of simulations, which have a comoving volume of (95.5 Mpc)^3. Specifically, we show that if we fit the EFT coefficients in a small ~5% sub-volume of the simulation, we can accurately predict the 21cm field in the rest of the simulation given only the linear density field. We show that our technique is robust to different models of dark matter and differences in the sub-grid reionization modeling.

    ↳ astro-ph.COhep-ph4 citations
31. 31*

    Anatomy of Parity-violating Trispectra in Galaxy Surveys

    Yunjia Bao🇺🇸 · Lian-Tao Wang🇺🇸 · Zhong-Zhi Xianyu🇨🇳 · Yi-Ming Zhong🇨🇳

    Parity-violating interactions are ubiquitous phenomena in particle physics. If they are significant during cosmic inflation, they can leave imprints on primordial perturbations and be observed in correlation functions of galaxy surveys. Importantly, parity-violating signals in the four-point correlation functions (4PCFs) cannot be generated by Einstein gravity in the late universe on large scales, making them unique and powerful probes of high-energy physics during inflation. However, the complex structure of the 4PCF poses challenges in diagnosing the underlying properties of parity-violating interactions from observational data. In this work, we introduce a general framework that provides a streamlined pipeline directly from a particle model in inflation to galaxy 4PCFs in position space. We demonstrate this framework with a series of toy models, effective-field-theory-like models, and full models featuring tree-level exchange-type processes with chemical-potential-induced parity violation. We further showed the detection sensitivity of these models from BOSS data and highlighted potential challenges in data interpretation and model prediction.

    ↳ astro-ph.COhep-phhep-thPRD(2025)·12 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.