Thu·Jan 15, 2026Thursday·January 15, 2026

1. 01*

   Searching for Quirks at LHCb

   Xabier Cid Vidal🇪🇸 · Miguel Fernández Gómez🇪🇸 · Matthew Low🇺🇸 · Alejandro Novo Cal🇪🇸 · Yuhsin Tsai🇺🇸 · Carlos Vázquez Sierra🇪🇸

   Quirks are heavy particles connected by a flux tube from a hidden confining force that remain weakly constrained in large regions of their parameter space. This flux tube acts as a string that, at short enough distance, stretches as the quirk pair separates, then pulls the pair back together leading to interesting dynamics. We propose a novel search using the LHCb Vertex Locator (VELO), whose forward geometry and software-based trigger are uniquely suited to detecting the characteristic back-to-back, planar hit patterns produced by quirk pairs with little transverse recoil. Using detailed simulations of the VELO geometry, together with simple geometric selections, we present different sensitivity projections, demonstrating that LHCb can probe parameter regions inaccessible to existing ATLAS and CMS searches and offering a powerful, complementary path toward discovering quirks.

   hep-phhep-exJHEP(2020)·3 citations
2. 02*

   Heavy Neutrinos across the Electroweak-to-Multi-TeV Frontier via Novel ML-Enhanced Probes

   Yin-Fa Shen🇺🇸 · Alfredo Gurrola🇺🇸 · Francesco Romeo🇺🇸 · Denis Rathjens🇺🇸 · Andres Flórez🇨🇴

   We propose a new strategy to probe heavy neutrinos with non-universal fermion couplings at the Large Hadron Collider (LHC) using a novel production mechanism and machine-learning algorithms. Focusing on proton--proton collisions at $\sqrt{s}=13.6\mathrm{TeV}$, we investigate final states containing a charged lepton, missing transverse energy, and two jets. For heavy neutrino masses below $\mathcal{O}(1\mathrm{TeV})$, production is dominated by the $s$ channel process. At higher masses, vector boson fusion becomes the dominant production mechanism, with cross sections that decrease slowly as the heavy neutrino mass increases. We simulate both signal and Standard Model background events and employ gradient-boosted decision trees to optimize event classification. Assuming an integrated luminosity of $3000\mathrm{f}{\mathrm{b}}^{-1}$, expected for the high-luminosity, and considering realistic statistical and systematic uncertainties, we find that heavy neutrinos in the mass range $50\mathrm{GeV}$--$10\mathrm{TeV}$ can be probed with sensitivity to the mixing parameter $|V_{\ell N}{|}^2$ spanning from $\mathcal{O}(10^{-5})$ to 1. This approach enhances the discovery potential for heavy neutrinos and provides a complementary pathway to existing search strategies.

   hep-ph1 citation
3. 03*

   Spontaneous Cogensis by QCD axion in Type I Seesaw

   Eung Jin Chun🇰🇷

   We propose a generic axion--driven cogenesis scenario in which both the baryon asymmetry and dark matter abundance originate from the kinetic misalignment. The framework unifies the Peccei--Quinn (PQ) mechanism with a Type--I seesaw sector, where Hubble--induced masses and higher-dimensional PQ--violating operators drive early--time axion rotation. Working within the DFSZ axion model augmented by heavy neutrinos, we identify the parametric window of right-handed neutrino masses, determined by its decay rate, and the range of Hubble scales compatible with successful cogenesis, while maintaining the axion solution to the strong CP problem and satisfying current limits on axion isocurvature perturbations. Our results establish kinetic axion misalignment as a robust and predictive mechanism for axion cogenesis, independent of the inflationary microphysics.

   hep-phPRD(2026)·4 citations
4. 04*

   Light neutrinophilic WIMP in the $U(1{)}_{\mathrm{B}-\mathrm{L}+\mathrm{xY}}$ model

   Tatsuya Aonashi🇯🇵 · Shigeki Matsumoto🇯🇵 · Yu Watanabe🇺🇸 · Yuki Watanabe🇯🇵

   Sub-GeV dark matter is an appealing thermal target because it can still be produced via the standard freeze-out mechanism; at such low masses, achieving freeze-out naturally points to the presence of a light mediator, which shifts the most promising discovery avenues from the energy frontier to the intensity frontier. Realizing this picture is nonetheless challenging, since CMB observations tightly constrain energy injection from dark-matter annihilation at recombination and therefore strongly disfavor simple $s$-wave annihilation into visible Standard-Model final states. In this work, we propose a concrete neutrinophilic framework for sub-GeV thermal dark matter (''light WIMPs'') based on an additional gauge symmetry $\mathrm{U}(1{)}_{\mathrm{B}-\mathrm{L}+x\mathrm{Y}}$; for an appropriate choice of $x$, the new gauge boson couples predominantly to dark matter and neutrinos while its couplings to charged leptons are suppressed, so that sub-GeV dark matter annihilates almost exclusively into neutrinos, with hadronic modes kinematically closed. We map the parameter space in which the observed relic abundance is reproduced via standard thermal freeze-out in a conventional cosmological history, and show that sizable regions remain viable after imposing current cosmological, indirect-detection, and terrestrial constraints; in part of the allowed parameter space, the dark matter also exhibits sufficiently large self-interactions to potentially alleviate small-scale structure tensions.

   hep-phJHEP(2026)·0 citations
5. 05*

   Near-threshold photon-proton production of $J/\psi$ and ${\rm Y}$

   Chentao Tan🇨🇳 · Zhun Lu🇨🇳

   We study the near-threshold exclusive photoproduction of heavy vector mesons (quarkonia $J/\psi$ and ${\rm Y}$) off the proton within the framework of generalized parton distribution (GPD) factorization. The gluon GPDs are computed using a spectator model in which the proton emits a gluon and the remaining constituents are treated as a single spectator particle. Model parameters are determined by fitting the gluon unpolarized and helicity collinear parton distribution functions (PDFs) from global analyses. We compare our results with the latest near-threshold $J/\psi$ production data from the GlueX and $J/\psi$-007 experiments at Jefferson Laboratory, finding good agreement for both differential and total cross sections. Predictions are also provided for ${\rm Y}$ photoproduction, which can be tested at future Electron-Ion Colliders.

   hep-phhep-exPRD(2026)·0 citations
6. 06*

   Explicit rephasing to Kobayashi-Maskawa representation and fundamental phase structure of CP violation

   Masaki J. S. Yang🇯🇵

   In this letter, we construct an explicit rephasing transformation that converts an arbitrary unitary matrix into the Kobayashi--Maskawa (KM) parameterization and identify all independent CP phases in the mixing matrix as the arguments of its matrix elements. Furthermore, by applying this rephasing transformation to the fermion diagonalization matrices $U^f$, we show that the Majorana phases are represented by fermion-specific phases ${\delta }_{\mathrm{KM}}^{\nu ,e}$ and their relative phases. In particular, by neglecting the 3-1 elements $U_{31}^{\nu ,e}$ of the diagonalization matrices for the two fermions, the KM phase ${\delta }_{\mathrm{KM}}$ is concisely expressed by fermion-specific rephasing invariants involving two relative phases ${\delta }_{\mathrm{KM}}=\arg \left[1+(U_{21}^{e\ast }{U}_{21}^{\nu }/U_{11}^{e\ast }{U}_{11}^{\nu })\right]+\arg \left[-U_{32}^{e\ast }{U}_{32}^{\nu }/U_{22}^{e\ast }{U}_{22}^{\nu }\right]$.

   hep-phPTEP(2026)·4 citations
7. 07*

   Stationary perturbation theory without sums over intermediate states: Supersymmetric Expansion Algorithm

   M. Napsuciale🇲🇽 · S. Rodríguez🇲🇽

   In this work we show that results of Rayleigh-Schrödinger perturbation theory can be easily obtained using the recently proposed supersymmetric expansion algorithm. Our formalism avoids the sums over intermediate states and yield directly corrections to the energy and eigenstates in terms of integrals weighted by the probability densities for the edge states of the involved supersymmetric Hamiltonians.

   hep-phhep-thquant-ph0 citations
8. 08*

   SMEFT effects on spin correlations and entanglement at NLO QCD in di-boson production at hadron colliders

   Giovanni Pelliccioli🇮🇹 · Emanuele Re🇮🇹

   We perform for the first time a full study of spin correlations in inclusive WZ production at the LHC with leptonic decays in the presence of NLO QCD corrections and of effects from a dimension-six operator in the SMEFT modifying the electroweak triple-gauge coupling. We carry out the complete quantum-state tomography of the di-boson system and relate its results to common purity and spin-entanglement markers, highlighting the sizeable impact of both QCD corrections and SMEFT insertions. Additionally, we show how a naive truncation at dimension-six in the SMEFT expansion of the spin-density matrix can lead to a cumbersome spin interpretation of the quantum-tomography results.

   hep-phhep-exPRD(2026)·9 citations
9. 09*

   Modulus stabilization of modular flavor models in Jordan frame supergravity

   Fei Wang🇨🇳 · Ying Kai Zhang🇨🇳

   We propose to discuss the modular flavor model and the stabilization of single modulus field in the Jordan frame supergravity with non-minimal scalar-curvature coupling of the form $\Phi (\tau ,\bar{\tau })R$. Modular invariance, positivity of the scale factor and positive definiteness of the Kahler metric constrain stringently the form of the frame function, consequently the Kahler potential by the relation $\Phi (\tau ,\bar{\tau })=-3\exp [-K(\tau ,\bar{\tau })/3]$. We discuss some general properties of scalar potentials after the scale transformation from the Jordan frame to the Einstein frame. We find that the shape of the resulting scalar potential in the Einstein frame is quite different from that of ordinary single modulus stabilization mechanism. The scalar potential could be stationary at the $i\infty$ fixed point, leading to a runaway type vacuum. Such a runaway-type vacuum can be properly stabilized at typical modulus VEV with large $\Im \tau$. We also discuss numerically the modulus stabilization for some simplified scenarios.

   hep-phhep-thPRD(2026)·0 citations
10. 10*

    Quantum properties of heavy-fermion pairs at a lepton collider with polarised beams

    Mohammad Mahdi Altakach🇱🇧 · Priyanka Lamba🇮🇹 · Fabio Maltoni🇧🇪 · Kazuki Sakurai🇵🇱

    We investigate the quantum properties of heavy-fermion pairs, such as $t\bar{t}$ or ${\tau }^{+}{\tau }^{-}$, produced in lepton-lepton collisions with polarised beams. Focusing on spin correlations, entanglement, Bell-inequality violation, and quantum-information-theoretic measures such as purity and magic, we analyse how beam polarisation shapes the structure of the spin-density matrix. We derive analytic expressions for a wide range of helicity configurations, including both Standard Model contributions and generic new-physics effects parametrised by scalar, vector, and tensor four-fermion operators within an effective field theory framework. We show that beam polarisation unlocks a substantially richer set of spin configurations and significantly enhances sensitivity to non-standard interactions. As a phenomenological application, we study $t\bar{t}$ production at a future linear collider and demonstrate that quantum observables provide a comprehensive and complementary probe of top-quark interactions and stronger constraints on the scale of new physics.

    hep-phhep-exhep-thquant-phJHEP(2026)·19 citations
11. 11*

    New modular fixed point models and their phenomenological implications for JUNO, T2HK and DUNE

    Er-Hao Shang🇨🇳 · Jun-Nan Lu🇨🇳 · Gui-Jun Ding🇨🇳 · Stephen F. King🇬🇧

    We perform a general analysis of minimal modular fixed point models based on two right-handed neutrinos (2RHNs) and three modular fixed points, and find that the only viable possibilities are based on modular $S_4^{\prime }$ and $A_5$ symmetry. Such models are highly predictive, with neutrino masses and the lepton mixing mixing matrix being fixed by three real parameters, as in the Littlest Seesaw Models. We perform an exhaustive scan over all possible models in this class and find many viable fixed points and modular form alignments, after confronting them with the latest neutrino oscillation global fits. The resulting models have the new feature that the two Dirac columns take more general forms than traditional Littlest Seesaw models, resulting in new sum rule relations between the solar and reactor angles, beyond those associated with TM1 (where the first column of the tri-bimaximal mixing matrix is preserved), which are compared to present and future projected JUNO results. We also compare the predictions of these models for the atmospheric angle and CP violating phase to current global fits and future T2HK and DUNE sensitivities.

    hep-phJHEP(2026)·6 citations
12. 12*

    Higgs Decays at NLO in the SMEFT

    Luigi Bellafronte🇺🇸 · Sally Dawson🇺🇸 · Clara Del Pio🇺🇸 · Matthew Forslund🇺🇸 · Pier Paolo Giardino🇪🇸

    The calculation of precise predictions for Higgs decays is a necessary ingredient for determining Higgs properties at the LHC and future colliders. We compute all two- and three-body Higgs decays at next-to-leading order (NLO) in both QCD and electroweak interactions using the dimension-6 Standard Model Effective Field Theory (SMEFT). Results for four-body Higgs decays that are accurate to NLO QCD/electroweak order in the SMEFT are obtained using the narrow width approximation. Our results are contained in a flexible Monte Carlo program, NEWiSH, that is publicly available and we illustrate the impact of the NLO electroweak corrections for HL-LHC, Tera-Z, and Higgstrahlung projections.

    hep-phJHEP(2026)·8 citations
13. 13*

    Classical equipartition dynamics between axions and non-Abelian gauge fields

    Kim V. Berghaus🇺🇸 · Adrien Florio🇩🇪 · M. Laine🇨🇭 · Franz R. Sattler🇩🇪

    Motivated by axion-like inflation and its warm embedding within the Standard Model, we study the early stages of the energy transfer between an axion condensate and an SU(2) gauge ensemble, by employing non-linear classical real-time lattice simulations. The discretized equations of motion are worked out, elaborating on Gauss constraints. A numerical solution is implemented on the CosmoLattice platform. Adopting a quadratic potential, and omitting universe expansion, we establish initial exponential growth of the low-momentum gauge modes; damping of axion oscillations after some delay; and subsequent energy equipartition between axion and gauge ensembles. A clear difference between the SU(2) and U(1) dynamics is observed, likely associated with non-Abelian self-interactions. We elaborate on what this implies for the possible thermalization of the SU(2) ensemble.

    hep-phastro-ph.COhep-latJCAP(2026)·2 citations
14. 14*

    The Cosmic Neutrino Background is within Reach of Future Neutrino Telescopes

    Gonzalo Herrera🇺🇸 · Shunsaku Horiuchi🇺🇸 · Xiaolin Qi🇺🇸 · Ian M. Shoemaker🇺🇸

    The cosmic neutrino background (C$\nu$B) can be boosted to high energies due to scatterings with energetic cosmic rays (CRs) across cosmological scales. Previous calculations focused on neutral current incoherent and coherent elastic scatterings of cosmic-ray protons off relic neutrinos. However, charged current interactions and deep inelastic scatterings are also expected to occur, which enhances the boosted relic neutrino fluxes on Earth. Here, we compute the \textit{total} diffuse boosted cosmic neutrino background (DBC$\nu$B) arising from CRs at all redshifts in the Universe, accounting for neutral current and charged current elastic and deep inelastic scatterings. We find that IceCube already places an upper limit on the cosmic neutrino background overdensity in cosmological scales of ~$\mathcal{O}(100-1000)$ at $E_{\nu }=10^{10}$ GeV, for a lightest neutrino mass of $m_{\nu }\gtrsim 0.1$ eV. We further show that IceCube-Gen2 could test $\mathcal{O}(1-10)$ C$\nu$B overdensities, and the combination of $10$ future neutrino telescopes with similar sensitivity would allow us to test the $\Lambda$CDM expected C$\nu$B density for a lightest neutrino mass compatible with the KATRIN bound.

    hep-phastro-ph.COastro-ph.HE8 citations
15. 15*

    Lessons from the first JUNO results

    Ivan Esteban🇪🇸 · M.C. Gonzalez-Garcia🇺🇸 · Michele Maltoni🇪🇸 · Ivan Martinez-Soler🇬🇧 · Joao Paulo Pinheiro🇨🇳 · Thomas Schwetz🇩🇪

    First results from the JUNO reactor neutrino experiment already determine with world-leading precision the small neutrino squared-mass splitting $\Delta m_{21}^2$ and the mixing angle ${\theta }_{12}$. In this article we perform an exploratory study beyond these, taking advantage of the first JUNO data release to discuss its sensitivity to the large squared-mass splitting, $\Delta m_{3\ell }^2$. When combined with constraints from global oscillation data, this may already contain some information on the neutrino mass ordering. Indeed, we find that the combination of the complementary $\Delta m_{3\ell }^2$-determinations gives a slight preference for Normal Ordering, with a p-value for Inverted Ordering of 2%-2.6% ($2.2\sigma$-$2.3\sigma$). We study the robustness of this result with respect to potential systematic uncertainties and statistical fluctuations. Taken at face value, a full global analysis of oscillation data including the publicly available JUNO information and data leads to a preference for Normal Ordering with $\Delta {\chi }^2=4.6$ and 9.4 without and with Super-K and IceCube-24 atmospheric neutrino data, respectively.

    hep-phhep-exJHEP(2026)·24 citations
16. 16*

    Bogomol'nyi Equations in Two-Species Born--Infeld Theories Governing Vortices and Antivortices

    Aonan Xu🇨🇳 · Yisong Yang🇺🇸

    We derive several new Bogomol'nyi (self-dual) equations in two-species $U(1)\times U(1)$ gauge theories governed by the Born--Infeld nonlinear electrodynamics. By identifying appropriate Born--Infeld type Higgs potentials, we show that the highly nonlinear energy functionals admit exact topological lower bounds saturated by coupled first-order equations. The resulting models accommodate both vortex-vortex and vortex-antivortex configurations and generalize previously known single-species Born--Infeld systems to interacting multi-component settings. Beyond the derivation of the Bogomol'nyi equations, we develop an exact thermodynamic theory for pinned multivortex configurations in both the full plane and compact doubly periodic domains. Owing to the linear dependence of the Bogomol'nyi energy spectrum on topological charges, we obtain closed-form expressions for the canonical partition function, internal energy, heat capacity, and magnetization. In compact domains, the Bradlow type geometric bounds constrain admissible vortex numbers and lead to qualitatively new high-temperature behavior. In particular, vortex-only systems exhibit spontaneous magnetization, while vortex-antivortex systems do not, reflecting the underlying symmetry between opposite topological charges. These results provide a rare analytically solvable framework for studying thermodynamics in nonlinear multi-component gauge theories regulated by the Born--Infeld electrodynamics.

    ↳ hep-thhep-phmath-phmath.MP1 citation
17. 17*

    Ascertaining higher-order quantum correlations in high energy physics

    Ao-Xiang Liu🇨🇳 · Cong-Feng Qiao🇨🇳

    Nonlocality is a peculiar nature of quanta and it stands as an important quantum resource in application. Yet mere linear property of it, viz. the first order in moment, has been explored through various inequalities. Noticing the vast higher-order regime unexplored, in this study we investigate the higher-order quantum correlations in entangled hyperon-antihyperon system, which may be generated massively in charmonium decays. A new type of Clauser-Horne inequality for statistical cumulants and central moments is formulated. We find that a significant violation of the third-order constraint, indicating the existence of higher-order correlation, exists in hyperon-antihyperon system and can be observed in high energy physics experiments, like BESIII and Belle II. Notably, the violation manifests more in higher energy systems of the $\Lambda \bar{\Lambda }$ pair against the kinematic contamination of timelike events.

    ↳ quant-phhep-phAnnalen Phys.(2026)·0 citations
18. 18*

    Comments on Baryon Transition Form Factors

    Christoph Hanhart🇩🇪 · Maxim Mai🇺🇸 · Ulf-G. Meißner🇩🇪 · Deborah Rönchen🇩🇪

    We discuss in rather general terms the properties of space-like baryon transition form factors. In particular, we argue why these are necessarily complex-valued, what can be deduced from the respective phase motion and why dealing with real valued transition form factors in general leads to misleading results. For illustration the transition form factors for the Roper resonance as derived in the Jülich-Bonn-Washington framework are discussed.

    ↳ nucl-thhep-exhep-phnucl-exActa Phys.Polon.B(2026)·0 citations
19. 19*

    Collapse versus Disruption: The Fate of Compact Stellar Systems in Ultralight Dark Matter Halos

    Yu-Ming Yang🇨🇳 · Xiao-Jun Bi🇨🇳 · Long Wang🇨🇳 · Peng-Fei Yin🇨🇳

    Interference of the ultralight dark matter (ULDM) field generates time-varying gravitational potential fluctuations, which stochastically heat stellar systems embedded in ULDM halos. Small-sized stellar systems are therefore often used to set stringent constraints on ULDM. However, the evolution of systems with sizes well below the ULDM de Broglie wavelength remains poorly explored. Using numerical simulations, we show that the evolution of compact stellar systems in ULDM halos is governed by the interplay between internal stellar relaxation and ULDM-induced heating. We find the following main results. First, in sufficiently compact systems, relaxation-driven core collapse dominates, allowing the system to remain bound and dense, while ULDM-induced stripping of outer stars further accelerates the collapse. Second, in more extended systems, ULDM heating dominates and ultimately disrupts the system. Near the disruption threshold, we identify systems resembling ultra-faint dwarfs like Segue 1. Third, we further introduce a dimensionless parameter to quantify the relative importance of heating and relaxation and finally lead to an evolutionary phase diagram. Our results reveal the rich and nontrivial dynamics of compact stellar systems in ULDM halos, indicating that precise system modeling is essential for robust ULDM constraints.

    ↳ astro-ph.COastro-ph.GAhep-ph5 citations
20. 20*

    Inclusive and exclusive semileptonic decays of heavy mesons on the lattice

    Zhi Hu🇯🇵 · Alessandro Barone🇩🇪 · Ahmed Elgaziari🇬🇧 · Shoji Hashimoto🇯🇵 · Andreas Jüttner🇬🇧 · Takashi Kaneko🇯🇵 · Ryan Kellermann🇯🇵

    We report the recent progress from our group in extracting observables of both inclusive and exclusive semileptonic heavy-meson decays directly from lattice QCD four-point correlators. On the inclusive side, we illustrate how to estimate the systematic uncertainties from omitted higher-order terms and non-zero smearing of the kernel approximation, building on two important features of the Chebyshev expansion. On the exclusive side, we perform BCL parameterizations of the pseudoscalar to pseudoscalar form factors and compare the fitted coefficients with those from earlier results by HPQCD. We also perform a HQET-based parameterization of the P-wave form factors to shed new light on the 1/2-vs-3/2 puzzle. This work constitutes a step toward a unified lattice treatment of inclusive and exclusive semileptonic decays, relevant for the Vcb puzzle. In this study, we use lattice ensembles from the RBC/UKQCD collaboration for numerical investigations. Future developments from our group will focus on the control of other systematic effects for inclusive decays and investigations of other techniques with reduced statistical errors to extract exclusive contributions from lattice four-point correlators.

    ↳ hep-lathep-phPoS(2026)·1 citation
21. 21*

    The NANOGrav 15 yr Data Set: Piecewise Power-Law Reconstruction of the Gravitational-Wave Background

    Gabriella Agazie🇺🇸 · Akash Anumarlapudi🇺🇸 · Anne M. Archibald🇬🇧 · Zaven Arzoumanian🇺🇸 · Jeremy G. Baier🇺🇸 · Paul T. Baker🇺🇸 · Bence Bécsy🇺🇸 · Amit Bhoonah🇺🇸 · Laura Blecha🇺🇸 · Adam Brazier🇺🇸 · Paul R. Brook🇬🇧 · Sarah Burke-Spolaor🇺🇸 and 99 other authors

    The NANOGrav 15-year (NG15) data set provides evidence for a gravitational-wave background (GWB) signal at nanohertz frequencies, which is expected to originate either from a cosmic population of inspiraling supermassive black-hole binaries or new particle physics in the early Universe. A firm identification of the source of the NG15 signal requires an accurate reconstruction of its frequency spectrum. In this paper, we provide such a spectral characterization of the NG15 signal based on a piecewise power-law (PPL) ansatz that strikes a balance between existing alternatives in the literature. Our PPL reconstruction is more flexible than the standard constant-power-law model, which describes the GWB spectrum in terms of only two parameters: an amplitude A and a spectral index gamma. Concurrently, it better approximates physically realistic GWB spectra -- especially those of cosmological origin -- than the free spectral model, since the latter allows for arbitrary variations in the GWB amplitude from one frequency bin to the next. Our PPL reconstruction of the NG15 signal relies on individual PPL models with a fixed number of internal nodes (i.e., constant power law, broken power law, doubly broken power law, etc.) that are ultimately combined in a Bayesian model average. The data products resulting from our analysis provide the basis for fast refits of spectral GWB models.

    ↳ astro-ph.HEastro-ph.COgr-qchep-phApJL(2026)·5 citations
22. 22*

    Simultaneous determination of Hubble constant and cosmic baryon density: Forecasts for the synergy between FRBs and emerging probes

    Peng-Ju Wu🇨🇳 · Bo-Yang Zhang🇨🇳 · Ji-Guo Zhang🇺🇸 · Guo-Hong Du🇺🇸 · Shang-Jie Jin🇺🇸 · Xin Zhang🇺🇸

    Two of the most pressing challenges in cosmology are the persistent discrepancy in measurements of the Hubble constant, referred to as the Hubble tension, and the deficit of baryons in the local Universe, known as the missing baryon problem. Fast radio bursts (FRBs) provide a unique probe of both the Hubble constant $H_0$ and the cosmic baryon density ${\Omega }_{\mathrm{b}}$. However, constraints from FRBs alone suffer from a severe $H_0$-${\Omega }_{\mathrm{b}}$ degeneracy that prevents them from resolving either problem. We show that this degeneracy can be broken by combining FRBs with other emerging probes whose degeneracy directions differ in the $H_0$-${\Omega }_{\mathrm{b}}$ plane. Specifically, we quantify three multi-messenger approaches: FRBs paired with gravitational wave (GW) standard sirens, strong gravitational lensing (SGL) time delays, and 21 cm intensity mapping (IM) surveys. The combinations FRB+GW, FRB+SGL, and FRB+21 cm IM each deliver simultaneous constraints on $H_0$ and ${\Omega }_{\mathrm{b}}$ better than (1%, 1.5%) in the $\Lambda$CDM model, and when dynamical dark energy is introduced, the constraining precision degrades gracefully as model complexity increases. Furthermore, within a model-independent framework, both FRB+GW and FRB+SGL constrain $H_0$ and ${\Omega }_{\mathrm{b}}$ to precisions better than (1.5%, 3%). These precision levels are based on nominal observational expectations and would improve significantly under optimistic observational scenarios.

    ↳ astro-ph.COgr-qchep-ph3 citations
23. 23*

    Spatial Wilson Loops and Energy Loss for Heavy Quarks in Magnetized HQCD Model

    Irina Ya. Aref'eva🇷🇺 · Ali Hajilou🇷🇺 · Kristina Rannu🇷🇺 · Pavel Slepov🇷🇺

    We investigate the effective potential and the string tension for the spatial Wilson loop (SWL) in hot dense QGP with two types of anisotropy, i.e. external magnetic field and spatial anisotropy, employing a holographic approach for the heavy quark model. In this approach, the string is extended in the 5th, holographic direction and has a turning point either on a dynamical wall (DW) configuration or on the horizon configuration in the 5th direction. We obtain the magnetic catalysis behavior for a phase transition between DW and horizon configuration of the string. The structure of the phase diagram does not depend on the boundary conditions choice for the dilaton field. Inclusion of the external magnetic field and spatial anisotropy enhance the string tension in the horizon configuration, namely drag force. For the spatially isotropic case $\nu =1$ at different magnetic field values the string tension is proportional to $T^2$ and is qualitatively consistent with lattice results. However, for the anisotropic case, $\nu =4.5$, it deviates from the quadratic term.

    ↳ hep-thhep-lathep-phPRD(2026)·2 citations
24. 24*

    Constraining axion-like dark matter with a radio-frequency atomic magnetometer

    A. Rigoulet🇬🇷 · S. Nanos🇬🇷 · I. K. Kominis🇬🇷 · D. Antypas🇬🇷

    We report on a broadband search for axion-like-particle (ALP) interactions using a radio-frequency-operated ${}^{87}\mathrm{Rb}$ atomic magnetometer. The instrument provides wide spectral coverage and sensitivity to an oscillating pseudomagnetic field that may be generated by the gradient coupling of the ALP field to the constituent fermions of atoms. We search for an ALP-gradient signature in the mass range $2.40\times 10^{-10}\mathrm{eV}/c^2$--$2.11\times 10^{-9}\mathrm{eV}/c^2$. No statistically significant signatures of an oscillating magnetic field are observed, and we derive upper limits on the corresponding ALP-proton, -neutron and -electron couplings, $g_{\alpha pp}$, $g_{\alpha nn}$ and $g_{\alpha ee}$, respectively. The result on $g_{\alpha pp}$ improves over previous laboratory searches, while the limits on $g_{\alpha nn}$ and $g_{\alpha ee}$ complement earlier laboratory searches and astrophysical bounds. The work extends searches for ALP-fermion interactions into a mass region largely unexplored in a dark-matter context, demonstrating the potential of our method for broadband axion-like particle searches targeting the Galactic dark-matter halo.

    ↳ physics.atom-phhep-phPRD(2026)·0 citations
25. 25*

    Constant-roll $\beta$-exponential inflation: Palatini formalism

    Ozan Sargın🇹🇷

    This paper investigates the inflationary dynamics of a $\beta$-exponential potential model within the framework of non-minimally coupled quadratic $(R+R^2)$ gravity. The functional form of the adopted potential provides a well-motivated framework; its physical origin can be interpreted either as the stabilization dynamics of a radion field determining the size of the extra dimension in braneworld cosmology, or as a manifestation of the $q$-exponential function emerging naturally from Tsallis non-extensive thermodynamics. Utilizing the Palatini formalism, we derive an effective Einstein-frame generalized k-inflation theory and analyze its evolution under the constant-roll condition. We perform a comprehensive scan of the parameter space to obtain predictions for the spectral index $n_s$ and the tensor-to-scalar ratio $r$. Our results demonstrate that for specific viable ranges of the model parameters, the inflationary observables are in excellent agreement with the latest observational data from the Atacama Cosmology Telescope (ACT) DR6 and the Planck mission, thereby identifying the physically consistent regions of the parameter space. Furthermore, an evaluation of the primordial non-Gaussianity confirms that the constant-roll dynamics generate a distinct, observationally viable phenomenological signature.

    ↳ gr-qcastro-ph.COhep-ph1 citation
26. 26*

    Exploring the hadronic phase with momentum and azimuthal distribution of short-lived resonances and understanding the internal structure of exotic resonances with ALICE

    Hirak Kumar Koley🇮🇳

    Hadronic resonances are crucial probes to understand the various phases of matter created during relativistic heavy-ion collisions. Due to their short lifetimes, the yields of these resonances can be affected by competing rescattering and regeneration mechanisms in the final hadronic phase. Rescattering can alter the momentum of the resonance decay products, limiting their reconstruction through the invariant-mass technique, while pseudo-elastic scattering can regenerate them. Final state observables such as elliptic flow, transverse momentum spectra, and measured yields of resonances could be significantly modified due to the interaction in the hadronic phase. By comparing the yields of longer-lived resonances, such as the $\varphi$-meson with shorter-lived ones, such as the K${}^{\ast }$(892), it is possible to obtain information about the properties and timescales of the hadronic phase. This contribution presents new Run 3 results on production yields, spectra, and flow harmonics for K${}^{\ast }$(892) and $\varphi$(1020) in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.36 TeV obtained by the ALICE Collaboration. The results are compared with state-of-the-art models to interpret the underlying mechanism that can describe the experimental observations. In addition to probe hadronic phase, the study of resonances also offers valuable insights into the non-perturbative regime of Quantum Chromodynamics (QCD). Resonances such as the f${}_0$(980) and f${}_1$(1285) challenge the traditional quark model. Their structure is yet unknown as they could potentially be tetraquark states or meson-meson molecules. This contribution presents new measurements of exotic resonances such as f${}_0$(980), f${}_1$(1285), and the glueball candidates to get more insight into their internal structure.

    ↳ hep-exhep-phnucl-exPoS(2026)·0 citations
27. 27*

    Microscopic Description of Critical Bubbles

    Carlos Hoyos🇪🇸 · David Mateos🇪🇸 · Wilke van der Schee🇨🇭 · Javier G. Subils🇳🇱

    First-order phase transitions occur through the nucleation of critical bubbles of the stable phase within the metastable phase. Using holography, we present a fully microscopic description of these bubbles in a strongly coupled, four-dimensional gauge theory at finite temperature. In the gravitational dual, these bubbles correspond to static, inhomogeneous and unstable black-brane solutions with a localized deformation on the horizon. We construct these solutions across the entire metastable branch and compute the surface tension and the nucleation rate. We then compare these microscopic results with those obtained from a two-derivative effective action for the order parameter in two different scenarios. When the effective action is derived from the microscopic theory via holography, we find remarkable agreement. However, when the effective action is constrained only by the equation of state and dimensional analysis, significant discrepancies emerge. These discrepancies can be resolved if an additional constraint related to the surface tension is imposed.

    ↳ hep-thastro-ph.COgr-qchep-ph3 citations
28. 28*

    Thermodynamic characteristics of a Fermi gas with an invariant energy scale and its astrophysical implications

    Tiyasa Kar🇺🇸 · Atul Kedia🇺🇸 · Ramkumar Radhakrishnan🇺🇸

    We investigate the thermodynamics of a relativistic Fermi gas governed by a modified dispersion relation in the Magueijo Smolin (MS) formulation of Doubly Special Relativity (DSR), characterized by the presence of an invariant ultraviolet energy (deformation) scale. We study the system in two physically distinct regimes: the near degenerate low-temperature limit, and the high-temperature regime. In the low-temperature regime, we derive the thermodynamic quantities using the standard Sommerfeld expansion. In the high-temperature regime, we evaluate all thermodynamic quantities numerically from the exact grand canonical potential and demonstrate that the thermodynamics of the Fermi gas reduces to the standard relativistic ideal gas behavior. We apply the resulting low-temperature equation of state to study compact astrophysical objects, namely, non-rotating white dwarfs and neutron stars. Helium white dwarfs exhibit a strong dependence on the deformation scale, while white dwarfs composed of heavier elements are less affected. For neutron stars, the modified equation of state leads to configurations that are smaller in radius and lower in mass than that is produced by nucleonic equations of state. Our results highlight how modified relativity theories can be probed by studying astrophysical objects.

    ↳ astro-ph.HEgr-qchep-phEPJC(2026)·2 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.