Fri·Jul 4, 2025Friday·July 4, 2025

1. 01*

   Primordial high energy neutrinos: theoretical/observational constraints and sharp spectral features

   Nicolas Grimbaum Yamamoto🇧🇪 · Thomas Hambye🇧🇪

   Among the few ways that allow or could allow us to probe the early Universe from the observation of a flux of primordial particles, there is one possibility which has been little studied: the observation today of high energy neutrinos which could have been emitted shortly after the Big Bang, from the decay or annihilation of early universe relics. We perform a general study of such a possibility. To this end, we first emphasise that these neutrinos could display various kinds of sharp spectral features, resulting from the primary energy spectrum at emission, and from how this spectrum is smoothed by redshift and radiative correction effects. Next, we determine the ranges of mass (from a fraction of eV all the way to the Planck scale) and lifetime of the source particles along which we do not/we do expect that the sharp spectral feature will be altered by interactions of the neutrinos on their way to the detector, mainly with the cosmic neutrino background or between themselves. We also study the theoretical (i.e. mainly BBN and CMB) and observational constraints which hold on such a possibility. This allows us to delineate the regions of parameter space (mass, lifetime and abundance) that are already excluded, hopeless for future observation or, instead, which could lead to the observation of such neutrinos in the near future.

   hep-phastro-ph.HEJCAP(2025)·2 citations
2. 02*

   Probing Earth's core using atmospheric neutrino oscillations in the presence of NSI at INO-ICAL

   Krishnamoorthi J🇮🇳 · Anuj Kumar Upadhyay🇮🇳 · Anil Kumar🇮🇳 · Sanjib Kumar Agarwalla🇮🇳

   Neutrinos can serve as a complementary and independent tool to gravitational and seismic studies in exploring the interior of Earth, thanks to their unique properties: extremely low interaction cross sections and flavor oscillations. With the precise measurements of neutrino oscillation parameters and observation of the non-zero value of mixing angle ${\theta }_{13}$, it has become feasible to detect the forward scattering of GeV-energy atmospheric neutrinos passing through Earth with ambient electrons in the form of matter effects on neutrino oscillation probabilities. These matter effects depend on both the neutrino energy and electron density distribution along their path, making them ideally suited for exploring the inner structure of Earth. Furthermore, in the presence of non-standard interactions (NSI) of neutrinos with matter, oscillation patterns undergo additional modifications. In this study, we quantify the capability of an atmospheric neutrino experiment, such as a magnetized iron calorimeter detector, to validate the Earth's core and measure the position of the core-mantle boundary in the presence of NSI. We perform this study considering a three-layered density profile of Earth. Our analysis demonstrates that neutrino non-standard interactions impact these Earth tomography measurements in comparison to standard interactions.

   hep-phhep-exphysics.geo-phphysics.ins-detJHEP(2025)·4 citations
3. 03*

   ACT-Inspired Kaehler-Based Inflationary Attractors

   C. Pallis🇬🇷

   We develop a new class of cosmological attractors which are compatible with the recent ACT results. They are based on two types of fractional Kaehler potentials, K, for a gauge-singlet inflaton phi which reduce, along the inflationary path, to the form N/(1-phi^qM)^p with qM=1, 2 and 0.1< p<10. The combination of these K's with the chaotic potentials phi^n (where n=2, 4) within a non-linear sigma model leads to inflationary observables which are consistent with the current data and largely independent from qM and n. Endowing these K's with a shift symmetry we also offer a supergravity realization of our models introducing two chiral superfields and a monomial superpotential, linear with respect to the inflaton-accompanying field. The attainment of inflation with subplanckian inflaton values and the large values for the tensor-to-scalar ratio, which increases with N, are two additional attractive features of our proposal.

   hep-phastro-ph.COhep-thJCAP(2025)·30 citations
4. 04*

   Production of $\Xi (1530)$ in the $K^{-}p$ scattering process

   Quan-Yun Guo · Jing Liu · Peiwen Wu · Dian-Yong Chen

   In the present work, we examine the production of $\Xi (1530)$ in the $K^{-}p\to K^{+}\Xi (1530{)}^{-}$ and $K^{-}p\to K^0\Xi (1530{)}^0$ reactions utilizing an effective Lagrangian approach. To accurately fit the cross sections for both processes, we include nine $\Lambda$ and $\Sigma$ hyperons and their resonances in both $s$- and $u$-channel processes. Considering the discrepancy of the measured cross sections for $K^{-}p\to K^{+}\Xi (1530{)}^{-}$ within the range $\sqrt{s}=[2.087,2.168]\mathrm{GeV}$, we employ two distinct fitting strategies: a uniform weighting scheme (model A) and a different weighting approach (model B). A comparative analysis suggests that model A yields a superior global agreement with experimental data compared to model B. Beyond fitting the cross sections, we also estimate the individual contributions from various intermediate states. Our results reveal that the cross section arising from the $\Sigma (1193)$ intermediate process is dominant. Furthermore, we predict different cross sections for $K^{-}p\to K^{+}\Xi (1530{)}^{-}$ and $K^{-}p\to K^0\Xi (1530{)}^0$ at several representative center-of-mass energies, providing testable predictions for forthcoming J-PARC experiments.

   hep-phPRC(2025)·3 citations
5. 05*

   Analyzing $t\bar{t}Z$-couplings at the future $e^{-}p$ collider

   Katlego Machethe🇿🇦 · Pramod Sharma🇮🇳 · Mukesh Kumar🇿🇦 · Rafiqul Rahaman🇧🇷 · Bruce Mellado🇿🇦

   The proposed Large Hadron Electron Collider (LHeC), with center-of-mass energy of $\sqrt{s}\approx 1.3$ TeV, provides a clean and sensitive environment to probe the top quark's neutral current interactions with the $Z$ boson via the process $e^{-}p\to e^{-}t\bar{t}$. We investigate the precision with which the Standard Model (SM) $t\bar{t}Z$ couplings-the vector and axial-vector components ($\Delta C_{1V}$, $\Delta C_{1A}$)-can be measured, along with possible new physics effects parameterized by higher-dimensional operators inducing weak electric and magnetic dipole-like interactions ($C_{2V}$, $C_{2A}$). Focusing on the semileptonic decay channel, where either the top quark or anti-top decays leptonically to a positively charged lepton (${\ell }^{+}=e^{+},{\mu }^{+}$), we utilize the azimuthal angle difference $\Delta \varphi$ between the scattered electron and the charged lepton as the key observable. Using a one-parameter multi-bin ${\chi }^2$-analysis of this differential distribution, we find that constraints on $\Delta C_{1V}$ and $\Delta C_{1A}$ improve from order $10^{-1}$ at 50 fb${}^{-1}$ to order $10^{-2}$ at 1000 fb${}^{-1}$, corresponding to approximately 50% and 6% precision relative to their SM values. The anomalous tensor couplings $C_{2V}$ and $C_{2A}$ are constrained at the $10^{-1}$ level even at low luminosity and improve moderately with high luminosity. While the two-parameter analysis broadens the allowed regions due to parameter correlations, it retains competitive sensitivity, particularly for SM-like couplings. A systematic uncertainty of 5% is assumed throughout. These results highlight the LHeC's potential to provide complementary and competitive sensitivity to top-$Z$ couplings compared to current and future hadron and lepton collider capabilities.

   hep-phPRD(2025)·1 citation
6. 06*

   Non-Abelian chiral kinetic theory with self-consistent semiclassical expansion

   Xiao-Li Luo🇨🇳 · Shu-Xiang Ma🇨🇳 · Jian-Hua Gao🇨🇳

   We derive the chiral kinetic theory in a non-Abelian gauge field using a self-consistent semiclassical expansion. Within this new expansion scheme, we disentangle the Wigner equations up to second order and demonstrate that they do not introduce additional constraint equations. By integrating the covariant chiral kinetic equations in eight-dimensional phase space, we obtain the corresponding equations in seven-dimensional phase space. This reduction facilitates numerical simulations and practical applications.

   hep-phhep-thnucl-thJHEP(2026)·1 citation
7. 07*

   Masses of hidden-charm pentaquark states with $J^P={\frac{3}{2}}^{-}$

   Tao Li🇨🇳 · Hao-Song Li🇨🇳

   Within the heavy pentaquark chiral perturbation theory, we calculate the chiral corrections for $J^P={\frac{3}{2}}^{-}$ octet hidden-charm pentaquark masses up to next-to-leading order. Taking the LHCb-reported $P_{\psi }^N(4440)$ and $P_{\psi s}^{\Lambda }(4459)$ (with $J^P={\frac{3}{2}}^{-}$) as inputs, we predict the other two octet hidden-charm pentaquark states $P_{\psi s}^{\Sigma }(4483)$ and $P_{\psi ss}^N(4490)$ with $J^P={\frac{3}{2}}^{-}$. The results provide theoretical guidance for the further search of $P_{\psi s}^{\Sigma }$ and $P_{\psi ss}^N$ in experiments.

   hep-ph0 citations
8. 08*

   Matching from quark to hadronic operators: external source vs spurion methods

   Gang Li🇨🇳 · Chuan-Qiang Song🇨🇳 · Jiang-Hao Yu🇨🇳

   Various weak processes at the hadronic scale have been utilized to search for new physics at high energy scale, which can be described by the QCD chiral Lagrangian matched from the low-energy effective theory (LEFT). Utilizing the chiral symmetry $SU(2{)}_L\times SU(2{)}_R\to SU(2{)}_V$ at the quark and hadronic levels, we make a comprehensive comparison of various matching methods, including the external source method, conventional spurion method, and our systematic spurion method. Although different methods show agreements for dimension-6 LEFT operator matching, we find that for higher-dimensional operators, the external source method is quite limited or inapplicable, the conventional spurion methods needs to introduce more and more spurions, while our spurion method does not need to introduce any new spurions than the ones in the dimension-6 matching. Using minimal set of spurions, we thus establish an one-to-one correspondence between the LEFT and chiral operators, with several examples, such as derivative operators at dimensions 7 and 8 with a single bilinear, four-quark operators at the dimension-9 level with two quark bilinears, which can be applied to the study of neutrino/electron scatterings and neutrinoless double beta decay.

   hep-phnucl-thJHEP(2026)·2 citations
9. 09*

   LHC and dark matter implications of t-b-{\tau} Yukawa unification in split SUSY GUTs

   Mureed Hussain🇵🇰 · Rizwan Khalid🇵🇰 · Cem Salih Un🇹🇷

   We investigate a grand unification (GUT) inspired version of the minimal supersymmetric standard model (MSSM) based on a left-right symmetric $4$-$2$-$2$ gauge group, incorporating Yukawa coupling unification and current phenomenological constraints. Utilizing a split soft supersymmetry-breaking (SSB) parameter space motivated by flavor symmetries, we analyze the implications of recent results from ATLAS, CMS, LHCb, and dark matter direct detection experiments. Our numerical scans, conducted with SARAH and SPheno, identify viable low-energy regions consistent with third-generation Yukawa unification, the observed Higgs boson mass, dark matter relic density, and flavor observables such as $B\to X_s\gamma$, $B_s\to {\mu }^{+}{\mu }^{-}$ and $B_u\to \tau {\nu }_{\tau }$ . Our findings suggest that while current bounds severely constrain much of the MSSM-like parameter space, substantial regions remain experimentally viable and testable in the ongoing LHC run and next-generation dark matter experiments.

   hep-phPRD(2026)·1 citation
10. 10*

    Impact of one-loop corrections to trilinear scalar couplings on di-Higgs production in the RxSM

    Johannes Braathen🇩🇪 · Sven Heinemeyer🇪🇸 · Andrea Parra Arnay🇪🇸 · Alain Verduras Schaeidt🇩🇪

    We investigate di-Higgs production at the (HL-)LHC and possible high-energy future $e^{+}{e}^{-}$ colliders within the real Higgs singlet extension of the Standard Model (SM), the RxSM. This model has two CP-even Higgs bosons, $h$ and $H$, for which we assume $m_h\sim 125\text{ GeV}<m_H$. We analyse the effect of one-loop corrections to the two trilinear scalar couplings relevant for di-Higgs production, ${\lambda }_{hhh}$ and ${\lambda }_{hhH}$, by performing an extensive parameter scan within the RxSM. We find that the one-loop corrections have a strong impact on the total production cross-sections, as well as on the differential cross-sections with respect to the invariant di-Higgs mass, $m_{hh}$. We evaluate the sensitivity of the HL-LHC and a high-energy $e^{+}{e}^{-}$ collider with $\sqrt{s}=1\text{ TeV}$, the ILC1000, to probe BSM physics effects in these processes. We demonstrate that the RxSM can be distinguished from the SM for large parts of the sampled parameter space. The resonant $H$ structure in the $m_{hh}$ distribution, on the other hand, can be observed only if the corresponding couplings, in particular ${\lambda }_{hhH}$, are sufficiently large. Here the ILC1000 yields a substantially better sensitivity than the HL-LHC.

    hep-phEPJC(2025)·20 citations
11. 11*

    Gravitational Waves from Gauge Quanta Produced during Inflation

    Kai-Ge Zhang🇨🇳 · Jian-Feng He🇨🇳 · Chengjie Fu🇨🇳 · Zong-Kuan Guo🇨🇳

    A fast-rolling axion can transfer its kinetic energy to a gauge field via the Chern-Simons coupling, leading to copious production of gauge quanta, which can act as a source of gravitational waves (GWs) with potentially observable amplitudes. In this work, we investigate GW production in a spectator axion model when strong backreaction is taken into account. We find that decreasing the decay constant of the axion enhances GW production. Since the initial value of the axion is larger than its quantum fluctuations, such a condition imposes a lower bound on the axion dacay constant, which sets an upper bound on the amplitude of the energy spectrum of GWs. As a result, the amplitude of the predicted GW energy spectrum is lower than $10^{-10}$ in the nHz to mHz frequency range.

    hep-phastro-ph.COgr-qcPRD(2025)·4 citations
12. 12*

    The $\theta$-term effects on isospin asymmetric hot and dense quark matter

    Lei Zhang🇨🇳 · Lu-Meng Liu🇨🇳 · Mei Huang🇨🇳

    We investigate the impact of the CP-violating $\theta$ term on isospin symmetry breaking in quark matter and compact star properties using a two-flavor Nambu-Jona-Lasinio (NJL) model. By incorporating the $\theta$ parameter through the Kobayashi-Maskawa-'t Hooft (KMT) determinant interaction, we derive the thermodynamic potential and gap equations under finite temperature, baryon chemical potential, and isospin chemical potential. At zero temperature and baryon density, $\theta$ suppresses conventional chiral ($\sigma$) and pion ($\pi$) condensates while promoting pseudo-scalar ($\eta$) and scalar-isovector ($\delta$) condensates, thereby reducing the critical isospin chemical potential ${\mu }_I^{\text{crit}}$ for spontaneous symmetry breaking. For $\theta =\pi$, a first-order phase transition emerges at ${\mu }_I^{\text{crit}}=0.021$ GeV, accompanied by CP symmetry restoration. Extending the investigation to finite temperature and baryon chemical potential reveals that these $\theta$-term-induced effects persist. Axion effects (modeled via $\theta \equiv a/f_a$) stiffen the equation of state (EOS) of non-strange quark stars, increasing their maximum mass and radii, in agreement with multimessenger constraints from pulsar observations and gravitational wave events. These results establish $\theta$ as a critical parameter modulating both the Quantum Chromodynamics (QCD) phase structure and compact star observables.

    hep-phnucl-thPRD(2025)·2 citations
13. 13*

    The Yukawa potential of a non-homogeneous sphere, with new limits on an ultralight boson

    Pierre Fayet🇫🇷

    Extremely weak long-range forces may lead to apparent violations of the Equivalence Principle. The final MICROSCOPE result, leading at 95 % c.l. to $|\delta |<4.5\times 10^{-15}$ or $6.5\times 10^{-15}$ for a positive or negative Eötvös parameter $\delta$, requires taking into account the spin of the mediator, and the sign of $\Delta (Q/A_r{)}_{\mathrm{Ti}-\mathrm{Pt}}$ ($Q$ denoting the new charge involved). A coupling to $B-L$ or $B$ should verify $|g_{B-L}|<1.1\times 10^{-25}$ or $|g_B|<8\times 10^{-25}$, for a spin-1 mediator of mass $m<10^{-14}$ eV$/c^2$, with slightly different limits of $1.3\times 10^{-25}$ or $6.6\times 10^{-25}$ in the spin-0 case. The limits increase with $m$, in a way which depends on the density distribution within the Earth. This involves an hyperbolic form factor, expressed through a bilateral Laplace transform as $\Phi (x=mR)=⟨\sinh mr/mr⟩$, related by analytic continuation to the Earth form factor $\Phi (ix)=⟨\sin mr/mr⟩$. It may be expressed as $\Phi (x)=\frac{3}{x^2}(\cosh x-\frac{\sinh x}{x})\times \bar{\rho }(x)/{\rho }_0$, where $\bar{\rho }(x)$ is an effective density, decreasing from the average ${\rho }_0$ at $m=0$ down to the density at the periphery. We give general integral or multishell expressions of $\Phi (x)$, evaluating it, and $\bar{\rho }(x)$, in a simplified 5-shell model. $\Phi (x)$ may be expanded as $\sum \frac{x^{2n}}{(2n+1)!}\frac{⟨r^{2n}⟩}{R^{2n}}\simeq 1+.0827x^2+.00271x^4+4.78\times 10^{-5}{x}^6+5.26\times 10^{-7}{x}^8+...$, absolutely convergent for all $x$ and potentially useful up to $x\approx 5$. The coupling limits increase at large $x$ like $mR{e}^{mz/2}/\sqrt{1+mr}$ ($z=r-R$ being the satellite altitude), getting multiplied by $\simeq 1.9,34$, or $1.2\times 10^9$, for $m=10^{-13},10^{-12}$ or $10^{-11}$ eV$/c^2$, respectively.

    hep-phhep-exPRD(2025)·3 citations
14. 14*

    Constraining color-charge effects of partonic energy loss with jet axis-based inclusive jet substructure measurement

    Raghunath Pradhan🇺🇸 · Olga Evdokimov🇺🇸

    This study investigates the color-charge dependence of parton energy loss in the quark-gluon plasma (QGP) medium and the associated relative modifications of quark and gluon jet fractions compared to vacuum, using jet axis decorrelation observables. Recent CMS jet axis decorrelation measurements in PbPb collisions at 5.02 TeV are interpreted using Pythia simulations with varied quark/gluon jet compositions and emulated color-charge dependent energy loss. A template-fit procedure is employed to estimate the limits on gluon jet fractions in the published CMS data and average shift in jet momentum due to quenching for quark- and gluon-initiated jets traversing the QGP. The extracted gluon jet fractions and the estimated quark and gluon energy losses based on this study of jet axis decorrelations are found to be consistent with other model calculations based on inclusive observables. This work illustrates the use of jet substructure measurements for providing constraints on the color-charge dependence of parton energy loss and offers valuable insights for jet quenching models.

    hep-phhep-exnucl-exnucl-thPRC(2025)·0 citations
15. 15*

    Neutrino mixing parameters and masses from $\Delta (96)⋊H_{CP}$ in the tri-direct CP approach

    Li-Na Yan🇨🇳 · Xiang-Yan Gao🇨🇳 · Gao-Da Liu🇨🇳 · Cai-Chang Li🇨🇳

    We present a comprehensive model independent analysis of all breaking patterns resulting from $\Delta (96)⋊H_{CP}$ in the tri-direct CP approach of the minimal seesaw model with two right-handed neutrinos. The three generations of left-handed lepton doublets are assumed to transform as the irreducible triplet $3_0$ of $\Delta (96)$, and the two right-handed neutrinos are assigned to singlets. In the case that both flavon fields ${\varphi }_{\text{atm}}$ and ${\varphi }_{\text{sol}}$ transform as triplet ${\bar{3}}_0$, only one phenomenologically viable lepton mixing pattern is obtained for normal ordering neutrino masses. The lepton mixing matrix is predicted to be the TM1 pattern, with neutrino masses, mixing angles, and CP violation phases depending on only three real input parameters. When ${\varphi }_{\text{sol}}$ is assigned to the ${\bar{3}}_1$ representation, an additional real parameter $x$ must be included. Then we find 42 (12) independent phenomenologically interesting mixing patterns for normal (inverted) ordering neutrino masses, and the corresponding predictions for lepton mixing parameters and neutrino masses are obtained. Furthermore, we perform a detailed numerical analysis for five (one) example breaking patterns with some benchmark values of $x$ for normal (inverted) ordering. For the five normal examples, the absolute values of the first columns of the PMNS matrix are fixed to be ${\left(\sqrt{\frac{2}{3}},\frac{1}{\sqrt{6}},\frac{1}{\sqrt{6}}\right)}^T$, $\frac{1}{5}{\left(\sqrt{17},2,2\right)}^T$, $\frac{1}{\sqrt{38}}{\left(5,2,3\right)}^T$, $\frac{1}{\sqrt{57}}{\left(\sqrt{37},\sqrt{10},\sqrt{10}\right)}^T$ and $\frac{1}{3}{\left(\sqrt{6},1,\sqrt{2}\right)}^T$, respectively. For the inverted example, the absolute value of the third column of the PMNS matrix is $\frac{1}{2\sqrt{11}}{\left(1,5,3\sqrt{2}\right)}^T$.

    hep-phJHEP(2025)·2 citations
16. 16*

    Soft background fields at next-to-leading power in transverse momentum dependent SIDIS with jets

    Max Jaarsma🇳🇱 · Oscar del Rio🇪🇸 · Ignazio Scimemi🇪🇸 · Wouter Waalewijn🇳🇱

    We present a factorization formula for the $e+h\to e+\text{jet}+X$ cross section at small transverse momenta up to next-to-leading power (NLP), derived using the background field method (BFM) with explicit inclusion of soft modes. We discuss the relation between soft modes and overlap subtractions at NLP, showing that the inclusion of soft modes enables a definition of twist-3 operators with properly subtracted rapidity and endpoint divergences. We also derive the effective current operator at NLP and identify additional structures compared to previous approaches based on soft-collinear effective theory and the BFM without soft modes. Nevertheless, for the hadronic tensor, we find agreement at the perturbative order that we are working at, and identify a condition that needs to be satisfied for this agreement to extend to higher orders. Furthermore, we construct the most general form factors for this process, taking into account the polarization of the initial states. These involve perturbatively-calculable jet functions, opening a path to precise determinations of twist-3 hadronic distributions. Finally, our formalism is illustrated with phenomenological results for a specific azimuthal asymmetry, whose leading-logarithmic contribution depends solely on a twist-3 hadronic distribution and a twist-2 jet function.

    hep-phnucl-thJHEP(2025)·8 citations
17. 17*

    Cornering Natural SUSY at a Tera-$Z$ Factory

    Admir Greljo🇨🇭 · Ben A. Stefanek🇪🇸 · Alessandro Valenti🇨🇭

    The future circular $e^{+}{e}^{-}$ collider (FCC-ee) stands out as the next flagship project in particle physics, dedicated to uncovering the microscopic origin of the Higgs boson. In this context, we assess indirect probes of the Minimal Supersymmetric Standard Model (MSSM), a well-established benchmark hypothesis, exploring the complementarity between Higgs measurements and electroweak precision tests at the $Z$-pole. We study three key sectors: the heavy Higgs doublet, scalar top partners, and light gauginos and higgsinos, focusing on the parameter space favored by naturalness. Remarkably, the Tera-$Z$ program consistently offers significantly greater indirect sensitivity than the Mega-$h$ run. While promising, these prospects hinge on reducing SM uncertainties. Accordingly, we highlight key precision observables for targeted theoretical work.

    hep-phhep-exhep-thPLB(2025)·7 citations
18. 18*

    Examining the Anomalous Nature of Chiral Effects in Thermodynamics

    Rémy Larue🇨🇳 · Jérémie Quevillon🇫🇷 · Diego Saviot🇫🇷

    Quantum anomalies give rise to novel transport phenomena, including the generation of a current in a relativistic fluid due to the presence of magnetic field or vorticity. We present an exclusive and direct computation of the chiral anomaly within the path integral for a massless fermion on a generic electromagnetic and curved background, including local temperature and chemical potential. We identify new thermodynamical contributions to the anomaly which induce the Chiral Separation and Vortical Effects. Additionally, we show that the anomaly fully vanishes at global equilibrium.

    ↳ hep-thcond-mat.stat-mechhep-ph2 citations
19. 19*

    Testing T2K's Bayesian constraints with priors in alternate parameterisations

    The T2K Collaboration: K. Abe · S. Abe · R. Akutsu · H. Alarakia-Charles · Y.I. Alj Hakim · S. Alonso Monsalve · L. Anthony · S. Aoki · K.A. Apte · T. Arai · T. Arihara · S. Arimoto and 391 other authors

    Bayesian analysis results require a choice of prior distribution. In long-baseline neutrino oscillation physics, the usual parameterisation of the mixing matrix induces a prior that privileges certain neutrino mass and flavour state symmetries. Here we study the effect of privileging alternate symmetries on the results of the T2K experiment. We find that constraints on the level of CP violation (as given by the Jarlskog invariant) are robust under the choices of prior considered in the analysis. On the other hand, the degree of octant preference for the atmospheric angle depends on which symmetry has been privileged.

    ↳ hep-exhep-phEPJC(2025)·1 citation
20. 20*

    On discrete gauging and non-invertible selection rules

    Jun Dong🇯🇵 · Tim Jeric🇯🇵 · Tatsuo Kobayashi🇯🇵 · Ryusei Nishida🇯🇵 · Hajime Otsuka🇯🇵

    We clarify selection rules of conjugacy classes of several finite discrete groups where we deal with both gauged and ungauged cases. We find that the selection rules enjoy finite Abelian or non-Abelian discrete symmetries originating from the inner and/or outer automorphism of underlying discrete groups. Since the selection rules of conjugacy classes do not obey conventional group-like selection rules, they open up new coupling selection rules of fields which are labeled by the conjugacy classes.

    ↳ hep-thhep-phPRD(2026)·27 citations
21. 21*

    Primordial regular black holes as all the dark matter. III. Covariant canonical quantum gravity models

    Marco Calzà🇮🇹 · Davide Pedrotti🇮🇹 · Guan-Wen Yuan🇮🇹 · Sunny Vagnozzi🇮🇹

    In earlier companion papers, we showed that non-singular primordial black holes (PBHs) could account for all the dark matter (DM) over a significantly wider mass range compared to Schwarzschild PBHs. Those studies, mostly based on phenomenological metrics, are now extended by considering the quantum-corrected space-time recently proposed by Zhang, Lewandowski, Ma and Yang (ZLMY), derived from an effective canonical (loop) quantum gravity approach explicitly enforcing general covariance. Unlike the BHs considered earlier, ZLMY BHs are free from Cauchy horizons, and are hotter than their Schwarzschild counterparts. We show that this higher temperature boosts the evaporation spectra of ZLMY PBHs, tightening limits on their abundance relative to Schwarzschild PBHs and shrinking the asteroid mass window where they can constitute all the DM, a result which reverses the earlier trend, but rests on firmer theoretical ground. While stressing the potential key role of quantum gravity effects in addressing the singularity and DM problems, our study shows that working within a consistent theoretical framework can strongly affect observational predictions.

    ↳ gr-qcastro-ph.COhep-phhep-thPRD(2025)·39 citations
22. 22*

    Estimation of gravitational production uncertainties

    Jose A. R. Cembranos🇪🇸 · Luis J. Garay🇪🇸 · Álvaro Parra-López🇪🇸 · Javier Ortega del Río🇪🇸

    Cosmological production of scalar, non-minimally coupled dark matter depends on the specifics of the inflationary model under consideration. We analyze both Starobinsky inflation and a quadratic potential, solve the full background dynamics, study pair production during inflation and reheating, and find that the observed dark matter abundance can be explained solely by this mechanism, regardless of the inflationary model. Qualitative differences between the two cases only appear for dark matter masses close to the inflationary scale. In addition, we identify a large region in parameter space in which cosmological production of dark matter is mostly independent of the chosen inflationary potential, highlighting the robustness of this dark matter production mechanism and its independence of the unknown particular details of inflation. In the region of masses lower than the scale of inflation, and sufficiently away from the conformal limit, the total comoving number density of produced particles becomes a function of the coupling to the geometry alone. This allows us to provide an approximated analytic expression for fitting the resulting abundance.

    ↳ gr-qchep-phhep-thJCAP(2026)·2 citations
23. 23*

    Extended momentum-dependent interaction for transport models and neutron stars

    Si-Pei Wang🇨🇳 · Lie-Wen Chen🇨🇳

    The momentum-dependent interaction (MDI) model, which has been widely used in microscopic transport models for heavy-ion collisions (HICs), is extended to include three different momentum-dependent terms and three zero-range density-dependent terms, dubbed as MDI3Y model. Compared to the MDI model, the single-nucleon potential in the MDI3Y model exhibits more flexible momentum-dependent behaviors. Furthermore, the inclusion of three zero-range density-dependent interactions follows the idea of Fermi momentum expansion, allowing more flexible variation for the largely uncertain high-density behaviors of nuclear matter equation of state (EOS), especially the symmetry energy. Moreover, we also obtain the corresponding Skyrme-like energy density functional through density matrix expansion of the finite-range exchange interactions. Based on the MDI3Y model, we construct four interactions with the same symmetry energy slope parameter $L=35$ MeV but different momentum dependence of $U_{\mathrm{sym}}$, by fitting the empirical nucleon optical potential, the empirical properties of symmetric nuclear matter, the microscopic calculations of pure neutron matter EOS and the astrophysical constraints on neutron stars. In addition, two interactions with $L=55$ and $75$ MeV are also constructed for comparison. Using these MDI3Y interactions, we study the properties of nuclear matter and neutron stars. These MDI3Y interactions, especially those with non-monotonic momentum dependence of $U_{\mathrm{sym}}$, will be potentially useful in transport model analyses of HICs data to extract nuclear matter EOS and the isospin splitting of nucleon effective masses.

    ↳ nucl-thastro-ph.HEhep-phnucl-exPRC(2025)·4 citations
24. 24*

    Theoretical insights on nuclear double parton distributions

    Federico Alberto Ceccopieri🇫🇷 · Filippo Fornetti🇮🇹 · Emanuele Pace🇮🇹 · Matteo Rinaldi🇮🇹 · Giovanni Salmè🇮🇹 · Nicholas Iles🇮🇹

    In this paper, we address double parton scattering (DPS) in pA collisions. Within the Light-Front approach, we formally derive the two contributions to the nuclear double parton distribution (DPD), namely: DPS1, involving two partons from the same nucleon, and DPS2, where the two partons belong to different parent nucleons. We then generalize the sum rule for hadron DPDs to the nuclear case and analytically show how all contributions combine to give the expected results. In addition partial sum rules for the DPDs related to DPS1 and DPS2 mechanisms are discussed for the first time. The deuteron system is considered for the first calculation of the nuclear DPD by using a realistic wave function obtained from the very refined nucleon-nucleon AV18 potential, embedded in a rigorous Poincaré covariant formalism. Results are used to test sum rules and properly verify that DPS1 contribution compares with the DPS2 one, although smaller. We also introduce EMC-like ratios involving nuclear and free DPDs to address the potential role of DPS in understanding in depth the EMC effect.

    ↳ nucl-thhep-phEPJC(2025)·2 citations
25. 25*

    Trans-series from condensates in the non-linear sigma model

    Yizhuang Liu🇵🇱 · Marcos Mariño🇨🇭

    In this work we provide a massless perturbative framework for the two dimensional non-linear sigma model (NLSM), that allows the computation of the perturbative series attached to the operator condensates in the operator product expansion (OPE). It is based on a limit of the quartic linear sigma model (LSM) and is manifestly $O(N)$ symmetric. We show, at next-to-leading order in the $1/N$ expansion, how this framework reproduces the perturbative contribution to the two-point function, as well as its first exponentially small correction due to the condensate of the Lagrangian operator, in full agreement with the exact non-perturbative large $N$ solution. We also show that, in the full LSM, the physics at the natural UV cutoff indeed decouples from the NLSM in the IR, in the weak-coupling limit. In particular, we show that the perturbative framework for the LSM at the cutoff scale is connected to the one in the NLSM. The structure of power divergences in the LSM regularization also reveals that the first renormalon on the positive Borel axis of the NLSM perturbative self-energy is an UV renormalon, which cancels against the ambiguity in the condensate.

    ↳ hep-thhep-phSciPost Phys.(2026)·7 citations
26. 26*

    Prospects for probing dark matter particles and primordial black holes with the Square Kilometre Array using the 21 cm power spectrum at cosmic dawn

    Meng-Lin Zhao🇺🇸 · Yue Shao🇺🇸 · Sai Wang🇨🇳 · Xin Zhang🇨🇳

    Probing the nature of dark matter (DM) remains an outstanding problem in modern cosmology. The 21 cm signal, as a sensitive tracer of neutral hydrogen during cosmic dawn, provides a unique means to investigate DM nature during this critical epoch. Annihilation and decay of DM particles, as well as Hawking radiation of primordial black holes (PBHs), can modify the thermal and ionization histories of the early universe, leaving distinctive imprints on the 21 cm power spectrum. Therefore, the redshifted 21 cm power spectrum serves as a powerful tool to investigate such DM processes. In this work, we systematically assess the potential of the upcoming Square Kilometre Array (SKA) to constrain DM and PBH parameters using the 21 cm power spectrum. Assuming $10,000$ hours of integration time, the SKA is projected to reach sensitivities of $⟨\sigma v⟩\le 10^{-28}{\mathrm{cm}}^3{\mathrm{s}}^{-1}$ and $\tau \ge 10^{28}\mathrm{seconds}$, for $10\mathrm{GeV}$ DM particles. It can also probe PBHs with masses of $10^{16}\mathrm{g}$ and abundances $f_{\mathrm{PBH}}\le 10^{-6}$. These results indicate that the SKA could place constraints on DM annihilation, decay, and PBH Hawking radiation that are up to two to three orders of magnitude stronger than current limits. Furthermore, the SKA is expected to exceed existing bounds on sub-GeV DM and to probe Hawking radiation from PBHs with masses above $10^{17}\mathrm{g}$, which are otherwise inaccessible by conventional cosmological probes. Overall, the SKA holds great promise for advancing our understanding of both DM particles and PBHs, potentially offering new insights into the fundamental nature of DM.

    ↳ astro-ph.COgr-qchep-phhep-thCPC(2026)·11 citations
27. 27*

    Axion USR Inflation

    Alireza Talebian🇮🇷 · Hassan Firouzjahi🇮🇷

    We consider a model of inflation in which the inflaton field is a rolling axion with a potential which is flat enough to support an intermediate phase of USR inflation. Because of the Chern-Simons interaction, one polarization of the gauge field experiences the tachyonic growth during the first slow-roll stage, inducing large corrections in curvature perturbations via the inverse decay effect. A non-trivial feature of our setup is that once the system enters the USR phase, the instability parameter falls off rapidly, terminating the gauge field production efficiently. Consequently, the power spectrum involves two separate peaks, the first peak is induced by the gauge field particles production while the second peak is due to standard USR mechanism. We show that the power spectrum at the intermediate scales develops strong scale-dependence $\propto k^m$ with the index $m>4$. Calculating the bispectrum, we demonstrate that non-Gaussianities with non-trivial shapes and multiple peaks are generated in this setup.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2025)·6 citations
28. 28*

    Cosmological constraints from UV/IR mixing

    Niccolò Cribiori🇧🇪 · Flavio Tonioni🇮🇹

    Holography and entropy bounds suggest that the ultraviolet (UV) and infrared (IR) cutoffs of gravitational effective theories are related to one another as a form of UV/IR mixing. Motivated by this, we derive a bound on the allowed scalar field range in theories with cosmic horizons. We show how this bound challenges several inflationary scenarios, such as $\alpha$-attractors and modular-invariant inflation. Besides, we find a relation between the number of extra spatial dimensions and the tensor-to-scalar ratio.

    ↳ hep-thastro-ph.COhep-phJHEP(2026)·14 citations
29. 29*

    Experimentally accessible drive-induced attractor in a Fermi gas near unitarity

    Michal P. Heller🇧🇪 · Clemens Werthmann🇧🇪

    Hydrodynamic attractors describe loss of sensitivity to initial conditions. Their earliest, expansion-driven stage is distinct from the later relaxation-driven mechanism and central to the theoretical paradigm but hard to access in heavy-ion collision experiments. We show within a coupled energy-bulk-pressure model that a near-unitary Fermi gas driven by a rapid scattering-length sweep loses sensitivity to one state-space direction before bulk relaxation sets in -- visible only in the joint state space, not as a universal single-variable curve. We outline an experimental ${}^{40}$K protocol based on time-resolved contact measurements and a varied-ramp comparison.

    ↳ hep-thcond-mat.quant-gashep-phnucl-th5 citations
30. 30*

    Reproducing Standard Model Fermion Masses and Mixing in String Theory: A Heterotic Line Bundle Study

    Andrei Constantin🇬🇧 · Lucas T.-Y. Leung🇬🇧 · Andre Lukas🇬🇧 · Luca A. Nutricati🇬🇧

    Deriving the Yukawa couplings and the resulting fermion masses and mixing angles of the Standard Model (SM) from a more fundamental theory remains one of the central outstanding problems in theoretical high-energy physics. It has long been recognised that string theory provides a framework within which this question can, at least in principle, be addressed. While substantial progress has been made in studying flavour physics in string compactifications over the past few decades, a concrete string construction that reproduces the full set of observed SM flavour parameters remains unknown. Here, we take a significant step in this direction by identifying two explicit $E_8\times E_8$ heterotic string models compactified on a Calabi-Yau threefold with abelian, holomorphic, and poly-stable vector bundles with an (MS)SM spectrum. Subject to reasonable assumptions about the moduli, we show that these models reproduce the correct values of the quark and charged lepton masses, as well as the quark mixing parameters, at some point in their moduli spaces. The resulting four-dimensional theories are $\mathcal{N}=1$ supersymmetric, contain no exotic fields and realise a $\mu$-term suppressed to the electroweak scale. While the issues of moduli stabilisation and supersymmetry breaking are not addressed here, our main result constitutes a proof of principle: there exist choices of topology and moduli within heterotic string compactifications which allow for an MSSM spectrum with the correct flavour parameters.

    ↳ hep-thhep-phPRD(2026)·8 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.