Wed·Dec 3, 2025Wednesday·December 3, 2025

1. 01*

   Linearly Polarized Gravitational Waves from Bubble Collisions

   Katarina Trailović🇸🇮

   Physics beyond the Standard Model may give rise to first-order phase transitions proceeding via the nucleation of vacuum bubbles, whose subsequent collisions generate gravitational waves (GWs). Their detection would open the possibility of investigating the universe in its first instants. If the transition is slow enough, such that it completes with the nucleation and collision of only two bubbles, the resulting GW signal is linearly polarized. This would give a unique signature for the origin of such a GW signal. We show that even though such phase transitions would be slow, they still could lie within the detectability range of GW interferometers such as LISA and the Einstein Telescope and the underlying two-bubble origin would be encoded in higher-order polarization statistics.

   hep-phastro-ph.CO0 citations
2. 02*

   Gravitational waves from flavoured SU(2) early-universe phase transitions

   Anna Chrysostomou🇫🇷 · Alan S. Cornell🇿🇦 · Luc Darmé🇫🇷 · Aldo Deandrea🇫🇷 · Thibault Demartini🇫🇷

   Flavourful extensions of the Standard Model aimed at explaining its fermionic mass structure typically rely on symmetries, broken at high-energy scales far beyond the reach of foreseeable direct collider searches. We illustrate, using a $SU(2)$ flavour gauge group, that the breaking of these symmetries up to scales as high as $10^7$ GeV could generate a gravitational-wave signal potentially observable by future observatories. We use dimensional reduction techniques to obtain the finite-temperature effective potential and study the possible first-order phase transitions. We match these transitions to steady-state hydrodynamical solutions in order to determine the corresponding gravitational-wave spectra. We observe that order-one gauge couplings are always required for a first-order phase transition to occur. On the other hand, adding leptoquarks (as an example of particles that are typically present in a complete flavour theory) significantly extends the testable parameter space. We find excellent prospects at the Einstein Telescope for future gravitational-wave detection of flavoured $SU(2)$ early-universe phase transitions.

   hep-phhep-thJHEP(2026)·4 citations
3. 03*

   Manual for SE+BSF4DM -- A micrOMEGAs package for Sommerfeld Effect and Bound State Formation in colored Dark Sectors

   Mathias Becker🇮🇹 · Emanuele Copello🇩🇪 · Julia Harz🇩🇪 · Martin Napetschnig🇩🇪

   This manual describes the usage and implementation of SE+BSF4DM, an add-on package for micrOMEGAs that includes the Sommerfeld effect and bound state formation in the numerical evaluation of the dark matter relic density for QCD-colored dark sectors, applicable to any model that can be mapped onto a simplified t-channel framework. The package seamlessly integrates these non-perturbative effects into the standard micrOMEGAs workflow, requiring minimal user modification. This document provides a comprehensive guide to the installation, configuration, and usage of SE+BSF4DM, serving as a practical user guide for dark matter phenomenologists.

   hep-ph4 citations
4. 04*

   Non-perturbaitve effects in Higgs boson decays to electroweak vector bosons and photons

   Alexander Khodjamirian🇩🇪 · Kirill Melnikov🇩🇪 · Arkady Vainshtein🇺🇸

   We estimate the magnitude of the leading non-perturbative QCD corrections to the decays of the Higgs boson to the $\gamma Z$ and $\gamma \gamma$ final states. These corrections originate from the light-quark contributions to such decays. We show that the non-perturbative effects are suppressed by the small Yukawa couplings of light quarks, but that there is no further quark-mass suppression. This is at variance with what is found in the standard perturbative calculations of the light-quark contributions. We demonstrate that the non-perturbative corrections modify the $H\to \gamma Z$ and $H\to \gamma \gamma$ decay rates by $O(10^{-5})$, well below the expected precision with which such decays can be studied both at the high-luminosity LHC and at future colliders.

   hep-phJHEP(2026)·1 citation
5. 05*

   Muon magnetic anomaly: experimental status and prospects

   Dinko Pocanic🇺🇸

   The past five years have brought significant new results on the muon magnetic anomaly, $a_{\mu }=(g_{\mu }-2)/2$, and on the hadronic vacuum polarization (HVP) contribution dominating the uncertainty $\Delta a_{\mu }$. Serious tension has emerged between the experimental and standard model(SM) values for $a_{\mu }$, as well as between the SM and the first precise lattice QCD values. We review the current experimental and theoretical status of $a_{\mu }$, along with the prospects for new results,focusing on MUonE,a new experiment at CERN, aiming to evaluate the leading order contribution to a(HVP) in a direct measurement of muonic Bhabha scattering.

   hep-phhep-exnucl-ex0 citations
6. 06*

   Impact of Higgs-boson measurements on SMEFT fits

   J. de Blas🇪🇸 · A. Goncalves🇺🇸 · V. Miralles🇬🇧 · L. Reina🇺🇸 · L. Silvestrini🇮🇹 · M. Valli🇮🇹

   We present current bounds on SMEFT operators that are mainly constrained by Higgs-boson observables, under different assumptions for the flavour structure of the UV theory. We investigate how the accuracy reached through a dedicated Higgs-boson precision physics program is starting to have a major impact in setting a lower bound on the scale of new physics, and we discuss the relevance of considering the scale evolution of the SMEFT coefficients in this context. We compare our results with the literature, pointing out the consistency of the results in spite of the different assumptions adopted in each analysis, and we discuss future steps aimed at improving the accuracy of the fit.

   hep-phhep-exSciPost Phys.Comm.Rep.(2026)·5 citations
7. 07*

   Non-diagonal DVCS with spinless hadron-to-two-hadron transition ${\gamma }^{\ast }\pi \to \gamma \pi \pi$

   Sangyeong Son🇰🇷

   We present the formalism of hadron-to-two-hadron transition generalized parton distributions (GPDs) for spinless hadron case. Definitions of the twist-2 unpolarized and polarized $\pi \to \pi \pi$ transition GPDs are introduced with a particular choice of kinematic variables that characterize the produced two-pion system. In the vicinity of $\rho (770)$, we work out the two-pion decay angular distributions of the $e^{-}\pi \to e^{-}\gamma \pi \pi$ cross section, incorporating both the Bethe-Heitler and deeply virtual Compton scattering processes. Each cross section exhibits a distinctive angular distribution, which is sensitive to the polarization states of the produced $\rho (770)$ resonance. In addition, we construct the double partial-wave expansion of $\pi \to \pi \pi$ transition GPDs in the two-pion decay angles as a generalization of GPDs for transition from a pion to a spin-$\ell$ resonance state. With the help of the Omnès representation, we constrain the $\pi \to \pi \pi$ transition GPDs in terms of the low energy $\pi \pi$ scattering phase shift and build a phenomenological model for these GPDs.

   hep-phnucl-thPoS(2026)·0 citations
8. 08*

   Properties of Stable Massive Quark Stars in Holography

   Kazem Bitaghsir Fadafan🇮🇷 · Jesús Cruz Rojas🇰🇷 · Jonas Mager🇦🇹

   We study a holographic D3/D7 system, whose dilaton profile has been phenomenologically adjusted in the infrared. The model is used to describe a deconfined yet massive quark phase of QCD at finite density, concluding that the equation of state of such a phase can be stiff enough to support exotic dense stars as massive as 2 solar masses. Nucleons are modeled phenomenologically using the Hebeler-et.al EFT baryon phases. For the stiff phenomenological baryon phases the transition to the quark phase is weakly first order allowing for stable quark cores. We also find that holographic baryons, modeled as wrapped D5-branes, provide unrealistic pressures (in the homogeneous approximation) and have to be discarded. We compute the mass vs. radius relation and tidal deformability for these hybrid stars. Contrary to a large number of other holographic models, this holographic model indicates that quark matter could be present at the core of heavy compact stars and may be used to explore the phenomenology of such objects.

   hep-phastro-ph.HEhep-th2 citations
9. 09*

   Relativistic correction to the binding energies of two-body hadronic molecular states

   Lin-Qing Song🇨🇳 · Hai-Qing Zhou🇨🇳

   This study presents a systematic estimation of the relativistic correction to the binding energies of two-body hadronic molecular states by comparing the numerical solutions of the three-dimensional (3D) Schrödinger, 3D Salpeter, and fully relativistic four-dimensional (4D) Bethe-Salpeter (BS) equations derived from the same underlying interaction. The numerical results reveal a counter-intuitive property: for hadronic molecular states whose binding energies are in the MeV range, the relativistic correction is unexpectedly large. This finding contradicts the conventional expectation that a heavier exchanged mass in the interaction implies suppressed relativistic effects. Specifically, we first benchmark the results using the Wick-Cutkosky model with a one-boson-exchange (OBE) interaction of mass $m_{ex}$, and then extend the analysis to the physical $D\bar{D}$ system. We find within the $1\sim 50$ MeV binding energy region, the relativistic correction is substantial, amounting to $-90\%\sim -70\%$ of the non-relativistic result. Such a significant correction strongly suggests that analyses based solely on the 3D Schrödinger or 3D Salpeter equations for hadronic molecular states should be treated with caution.

   hep-phhep-ex0 citations
10. 10*

    Unified Functional-Holographic Theory of the QCD Critical End Point

    Sameer Ahmad Mir🇨🇦 · Saeed Uddin🇮🇳 · Swatantra Kumar Tiwari🇮🇳 · Mir Faizal🇨🇦

    We develop a thermodynamically consistent nonperturbative framework for equilibrium QCD criticality, unifying DSE quark propagation, FRG flow, and PNJL thermodynamics for coupled chiral/deconfinement order parameters. A holographic Maxwell-Chern-Simons sector supplies topological response; its topological susceptibility enters the FRG flow of the determinantal ('t Hooft) interaction, encoding axial-anomaly evolution across the phase diagram. At ${\mu }_B=0$ we anchor to continuum-extrapolated lattice thermodynamics and conserved-charge susceptibilities through a lattice-calibrated Polyakov sector, enforcing exact thermodynamic identities by evaluating derivatives at the stationary grand-potential solution at each RG scale. Solving the coupled DSE-FRG-holographic system yields, at the present approximation level, an equilibrium critical end point at $T_{\mathrm{CEP}}\simeq 130\text{–}135,\mathrm{MeV}$ and ${\mu }_{B,\mathrm{CEP}}\simeq 600,\mathrm{MeV}$, with quantified sensitivity to regulator, Polyakov-sector, and holographic-normalization choices. The critical region is organized by a nonperturbative map onto universal 3D Ising scaling variables, with anomalous-dimension effects absorbed into nonuniversal metric factors, yielding predictions for the hierarchy, nonmonotonicity, and sign structure of higher-order net-baryon cumulant ratios along smooth freeze-out trajectories and speed-of-sound softening. Comparisons to RHIC BES fluctuation measurements are qualitative consistency checks on correlated equilibrium trends and sign patterns, because finite size/lifetime, critical slowing down, baryon-number conservation, acceptance/efficiency corrections, net-proton-to-net-baryon conversion, and baryon transport can round or reshape experimental cumulants. The results provide a unified equilibrium baseline and controlled inputs for finite-size scaling and dynamical embeddings of heavy-ion data.

    hep-phFortsch.Phys.(2026)·2 citations
11. 11*

    Probing fully coherent radiation and parton densities using (virtual) photons at the LHC

    François Arleo🇫🇷 · Djessy Bourgeais🇫🇷 · Maxime Guilbaud🇫🇷 · Greg Jackson🇫🇷 · Víctor Valencia Torres🇫🇷

    Prompt photon production in pA collisions has long been suggested as a sensitive probe of the nuclear parton distribution functions (nPDFs). In this study, we present recent results on another cold nuclear matter effect, namely fully coherent radiation induced by parton multiple scattering, which may influence the nuclear dependence of prompt photon production. Medium-induced radiation effects, implemented in leading-order direct and fragmentation photon processes, are computed for pPb collisions at the LHC. At backward rapidity, photons are sensitive to fully coherent energy loss (FCEL), while at forward rapidity, fully coherent energy gain (FCEG) plays a crucial role due to the dominance of the $qg\to q\gamma$ scattering channel. In contrast, for virtual photon production, the impact of fully coherent radiation is marginal, making Drell-Yan (DY) one of the best ways to probe nuclear PDFs. The power of the DY process is demonstrated by reweighting nPDF sets at next-to-leading order using realistic pseudo-data for LHC Run 3.

    hep-phhep-exPoS(2026)·0 citations
12. 12*

    Reevaluating the $a_1(1420)$ enhancement and its molecular partners in the low-lying axial-vector meson spectrum

    Mao-Jun Yan🇨🇳 · Chun-Sheng An🇨🇳 · Cheng-Rong Deng🇨🇳

    We assess possible axial-vector states with $G$-parity $\left(G=\pm 1\right)$ dynamically generated by pseudoscalar-vector interactions in coupled channels, driven by the Weinberg-Tomozawa term at leading order in chiral perturbation theory. The $S$-wave amplitudes are unitarized via the Bethe-Salpeter equation, and poles of the unitarized amplitudes are searched for in the complex energy plane. In the isovector sector with $I^G(J^{PC})=1^{\pm }(1^{+\mp })$, we identify two poles around 1400 MeV in the second Riemann sheet below the $K^{\ast }\bar{K}$ mass threshold. The $G=+1$ and $G=-1$ poles can be one of the origins of the peaks in the $f_0(980)\pi$ and $\varphi {\pi }^0$ mass spectra reported by the COMPASS and BESIII collaborations, respectively, in the $\pi N\to \pi \pi \pi N$ and $J/\psi \to \eta \varphi \pi$ processes, in addition to triangle singularity effects discussed in the literature. Additionally, the poles in the isoscalar sector may explain the nontrivial behavior of the $K^{\ast }\bar{K}$ spectra line shapes measured by several experiments in different reactions. Specifically, for the $0^{+}(1^{++})$ case, we find a sizeable $K^{\ast }\bar{K}$ component for the $f_1(1420)$. In the $0^{-}(1^{+-})$ scenario, the pole strongly coupled to $\rho \pi$ can be associated with the $h_1(1170)$ resonance. Lastly, in this same sector, we identify a higher pole that dominates the $K^{\ast }\bar{K}$ invariant mass in the ${\chi }_{cJ}\to \varphi K^{\ast }\bar{K}$ decay, where the \(h_1(1415)\) is observed in the BESIII data.

    hep-ph4 citations
13. 13*

    Exploring Leptogenesis, WIMP Dark Matter, and Gravitational Waves in an extended Scalar Framework

    Subhaditya Bhattacharya🇮🇳 · Niloy Mondal🇮🇳 · Arunansu Sil🇮🇳

    We explore extensions of type I seesaw framework with a scalar mediator ($\Phi$) connecting to a complex scalar dark field ($S$), and right handed neutrinos ($N_i$), with an aim to correlate neutrino mass generation, leptogenesis, and dark matter. ${\mathcal{Z}}_4\times CP$ turns out to be a phenomenologically viable choice of the extended symmetry, which can accommodate a dimension five effective interaction ${\bar{l}}_L^{\alpha }\tilde{H}\Phi N_i$, involving the SM lepton isodoublet $l_L$, and Higgs $H$; prohibiting the canonical Yukawa term ${\bar{l}}_L^{\alpha }\tilde{H}{N}_i$. The ${\mathcal{Z}}_4$ symmetry is spontaneously broken via the vacuum expectation value (VEV) of the $\Phi$ filed, which directly affects neutrino mass generation and leptogenesis; while the $CP$ symmetry stabilises one component of $S$, making it a viable dark matter candidate. The discrete symmetry breaking creates domain wall, which needs to be annihilated before the over-closure of the Universe. This paves the way for gravitational wave signal associated with the model set up, which probes the symmetry breaking scale, and indirectly connects to the other phenomena.

    hep-phastro-ph.CO1 citation
14. 14*

    Chen Ning Yang Retrospective

    Stephen L. Adler🇺🇸

    Chen-Ning Yang made important contributions to the theory of solvable models in statistical mechanics, including generalizations of the Bethe Ansatz, magnetization in the Ising model, the Lee-Yang circle theorem, and the Yang-Baxter equation. Most famously, Yang made transformative contributions to the current Standard Model of elementary particle interactions. The proposal of Yang and T. D. Lee, that left-right symetry (parity) is violated in weak particle decays, established that the primary currents involved in weak interactions are left handed. The work of Yang and R. L. Mills gave a framework for force carriers coupling to these currents that are non-Abelian generalizations of the electromagnetic photon, which unlike the electrically neutral photon, carry ``charges'' to which they self-couple . Two decades of work by others on quantization and mass-generation mechanisms then culminated in the Standard Model.

    hep-phhep-exhep-thmath-ph+20 citations
15. 15*

    Nucleon decays into three leptons: Noncontact contributions

    Jing Chen🇨🇳 · Yi Liao🇨🇳 · Xiao-Dong Ma🇨🇳 · Hao-Lin Wang🇨🇳

    We investigate baryon number violating (BNV) nucleon decays into three leptons from noncontact contributions that are induced by dimension-6 (dim-6) BNV operators in low-energy effective field theory (LEFT) with an exchange of a baryon, meson, lepton, or photon field. We systematically classify all these processes that change lepton flavor by one unit and formulate their decay widths in terms of the dim-6 LEFT Wilson coefficients. By applying constraints on these Wilson coefficients derived from current experimental limits on BNV two-body nucleon decays, we obtain stringent bounds on the rates of these triple-lepton modes. These bounds vary significantly from one dim-6 operator to another under consideration. Our results for the $\Delta (B-L)=0$ modes differ by several orders of magnitude from previous phase-space estimates in the literature, thereby providing a more reliable assessment of their potential occurrence. In addition, we provide improved bounds on $\Delta (B+L)=0$ modes compared to the existing experimental limits.

    hep-phPLB(2026)·2 citations
16. 16*

    Lepton Flavor Physics in the flipped 3-3-1-1 Model: Non-Universality and Violation

    D.T.Huong🇻🇳 · V.H.Binh🇻🇳 · N.T.Huong🇻🇳 · H.T.Hung🇻🇳 · Duong Van Loi🇻🇳 · D.T.Binh🇻🇳

    We investigate the flavor violation (FV) of Z decays to leptons at tree level and flavor conserving Z decays to leptons in the frame work of the flipped $SU(3{)}_C\otimes SU(3{)}_L\otimes U(1{)}_X\otimes U(1{)}_N$,(F3311) model. In addition, we analyze the processes $l_i\to l_j\gamma$ and the leptonic three-body decay. Using the experimental bounds on these decays we set the constraint on $\sin \varphi$ which represents the mixing between Z-Z' boson. The most stringent limits arises from $\mu \to e\gamma$ decay where $\sin \varphi \sim \mathcal{O}(10^{-3})$. The leptonic three-body decay set lower bound on the mass of the new neural gauge boson $m_{Z^{\prime }}\ge 3.2TeV$. Using the LUX-ZEPLIN (LZ) experiment data we set bounds to the mass of the dark matter candidates. Subsequently, we investigate the lepton non-universality in B decays within the $F3311$ model by calculating the generic one-loop contribution to the process $u_i\to d_j{e}_b{\bar{\nu }}_a$ in the unitary gauge as well as numerical evaluating the branching ratio $R_D,R_{D^{(\ast )}},R(X_c)$. We demonstrate that the $F3311$ model can address the $3.3\sigma$ discrepancies between Standard Model and experimental data. To reaffirm our results, we also analyze the $d\to u$ transitions and $s\to u$ transitions. These two transitions also give consistent result with experiment data. Combine all experiment dat a we obtain the operating region for the mass of the model specifically $m_E\in [6.5,9]TeV$, $m_Q\in [6,11]TeV$ and the dark matter candidate $m_{\xi }\in [1.5,2]TeV$.

    hep-phInt.J.Mod.Phys.A(2025)·1 citation
17. 17*

    Heavy sterile neutrinos in $B$ decays and new QCD corrections to their semi-hadronic decay rates

    Tim Kretz🇩🇪

    In modern experiments on flavour physics it is possible to search for the decays of $B$ or $D$ mesons or $\tau$ leptons into final states with heavy neutrinos $N$ (a.k.a. heavy neutral leptons). I present a common study of theorists and experimentalists from Belle II on constraints on $B\to D^{\ast }\ell N$. Next I discuss the status of the theory predictions of the various $N$ decay rates. In scenarios in which $N$ interacts with SM particles only through sterile-active neutrino mixing, the dependence of the lifetime on the relevant mixing angles is important to determine whether $N$ decays in the detector or outside. To calculate the inclusive decay rate into semi-hadronic final states reliably one needs to include radiative QCD corrections. I present analytic results for the QCD-corrected decay rates and discuss their phenomenological impact.

    hep-phPoS(2026)·0 citations
18. 18*

    Leptophilic Gauge Interactions in the SMEFT Era

    Seyit Okan Kara🇹🇷

    We develop a "precision-ready", model-independent EFT framework that connects general leptophilic gauge interactions to their low-energy manifestations in SMEFT and LEFT. Starting from a broad U(1)'_ell extension in which leptons carry family-dependent charges (q_e, q_mu, q_tau) while quarks remain neutral, quantum consistency is ensured through a minimal set of vectorlike leptons, chiral under U(1)'_ell but vectorlike under the SM, together with singlet scalars responsible for symmetry breaking and the masses of both Z_ell and the heavy leptons. In the heavy-mediator limit, we integrate out Z_ell at tree level and derive compact, analytic SMEFT Wilson coefficients for four-lepton operators and Higgs-current structures, including hypercharge-U(1)'_ell kinetic mixing proportional to Tr(Y Q'). Renormalization-group evolution down to the electroweak scale and matching onto LEFT produce closed-form expressions directly applicable to e+e- -> l+l-, neutrino trident production, nu e scattering, parity-violating Moeller observables, and muon-decay parameters. A single parameter combination, Lambda_eff = M_Zell / (g_ell * sqrt(|q q'|)), governs all leading EFT signatures, offering a unified way to map UV charge assignments onto precision observables. We delineate the validity domain of this EFT and outline its use as a "plug-and-play" interface for global fits, collider recasts, and future-collider projections.

    hep-ph0 citations
19. 19*

    Models for differential cross section in neutron-proton scattering and their implications

    Muhammad Saad Ashraf🇵🇰 · Nosheen Akbar🇵🇰

    A few analytic exponential models of elastic differential cross section, constructed as purely phenomenological models, are proposed and tested. The models incorporate energy-dependent exponential slopes, power-law prefactors, and localized Gaussian modifications which are built to reproduce the observed dip region, supplemented in some cases by logarithmic $t$-dependent slopes. Simple additive sub-leading exponential contributions that represent charge conjugation and isospin roles are introduced in the models to increase applicability and quality of fit across elastic differential cross section data of $np$, $n\bar{p}$, $pp$, and $p\bar{p}$ elastic scattering. The models reproduce the characteristic features of the elastic scattering data such as the dip-bump structure, shrinkage of the forward peak, and controlled curvature that is localized around the dip. Parameters of the models are found by fitting the experimental data of elastic $np$ differential cross section in an energy range of $\sqrt{s}$ = 3.36 GeV to 26.02 GeV, across a momentum range of $0.065\le \mid t\mid \le 5.341{\text{GeV}}^2$. The parameter values and their ranges, obtained by ${\chi }^2$ minimization are found within their assumed expected bounds with the $np$ data fitting. The total cross section, the slope parameter, the interaction radius, the total elastic cross section, the inelastic cross section, the ratios ${\sigma }_{el}/{\sigma }_{tot}$, and ${\sigma }_{inel}/{\sigma }_{tot}$ are predicted by the models for the $np$ scattering at all the energies, which show accurate quantitative agreement with their reference values. The results show that the proposed models not only provide accurate quantitative description of $np$ elastic differential cross section but also yield estimates of the observables that are consistent with theoretical expectations from Regge phenomenology and high-energy scattering constraints.

    hep-ph0 citations
20. 20*

    From Dark Sectors to the Axion-Neutrino Connection

    H. B. Câmara🇵🇹

    The Standard Model (SM) of particle physics provides a successful description of fundamental particles and their interactions but fails to explain phenomena such as neutrino oscillations, dark matter (DM), and the baryon asymmetry of the Universe. These clear signs of BSM physics motivate extensions introducing new particles and symmetries. Theoretical questions like the flavor puzzle and the strong CP problem further guide BSM frameworks. This thesis explores BSM scenarios based on two guiding principles: constructing unified frameworks that address multiple open problems in (astro)particle physics and cosmology, and emphasizing their experimental testability through detailed phenomenological analyses. This approach uncovers deep connections between seemingly disconnected sectors, offering a more complete view of fundamental physics. We investigate dark sector models for the origin of neutrino masses, proposing a novel setup: dark linear seesaw, which radiatively links neutrino mass generation to DM candidates and predicts charged lepton flavor violation. In these scenarios, dark sector particles can constitute WIMP DM, testable via direct detection experiments. We study spontaneous CP violation induced by a complex scalar singlet, acting as a common origin of low- and high-energy CP violating effects relevant for leptogenesis. We also analyze a Nelson-Barr model that solves the strong CP problem, generates a realistic CKM matrix radiatively, and yields scalar WIMP DM. Additionally, we present unified axion frameworks in which a colored sector radiatively generates neutrino masses. These models predict distinctive axion couplings to photons and fermions and accommodate axion DM in both pre- and post-inflationary cosmologies. Finally, we explore minimal flavored Peccei-Quinn symmetries that link the flavor puzzle, neutrino masses and DM within a predictive and testable framework.

    hep-ph0 citations
21. 21*

    All planar three-loop Feynman integrals for the production of two vector bosons at hadron colliders

    Dhimiter Canko🇮🇹 · Mattia Pozzoli🇮🇹

    We compute all the planar three-loop master integrals relevant for the leading colour N3LO QCD corrections to the production of two massive or off-shell vector bosons at hadron colliders. These integrals are organised into nine four-point integral families with massless internal propagators and two external massive legs. For each family, we construct a basis of pure master integrals and we reconstruct the corresponding canonical differential equations using finite field techniques. We evaluate the master integrals by solving the differential equations using generalised power series expansions.

    hep-phJHEP(2026)·1 citation
22. 22*

    The role of the top Yukawa coupling in triple Higgs production at the LHC

    Luca Panizzi🇮🇹

    In this letter I quantify the effects of varying the top Yukawa coupling in the process of production of three Higgs bosons at the LHC. Modifications of the coupling within experimentally observed ranges have a sizeable impact on the total cross-section, but do not have large effects on the distributions of the invariant mass of the three-Higgs system and other global observables.

    hep-phPRD(2026)·2 citations
23. 23*

    Modeling dark matter halos with self-interacting fermions: A polytropic approach

    Fabian Hernandez-Gutierrez🇲🇽 · Juan Barranco🇲🇽

    In this work we study the possibility of modeling the dark matter content in galaxies as a core-halo model consisting of self-gravitating, self-interacting fermions by means of an effective polytropic equation of state. For the core of the halo, the dark matter fermions are degenerate, while for the halo we have considered two possibilities: the fermions have thermalized as a perfect fluid, or they will follow a standard cold dark matter Navarro-Frenk-White profile. The core density profile is obtained by solving the Tolman-Oppenheimer-Volkoff equations, and their properties are determined by the fermion mass, the central density and the interaction strength. The mass of the fermion and the strength of the fermion self-interaction is fixed by doing a ${\chi }^2$ analysis to fit that fit the rotational curves of Low Surface Brightness galaxies. It was found that the fermion mass should be in the range $155.10\mathrm{eV}<{\mathrm{m}}_{\mathrm{f}}<313.26\mathrm{eV}$ and the interparticle strength in the range $1465.31<y<6002.04$ at $68$ C.L. in order to reproduce the rotational curves adequately, in the case when the halo is modeled as a thermalized ideal gas. Similar values are obtained if the halo is modeled following a Navarro-Frenk-White case, namely $42.31\mathrm{eV}<{\mathrm{m}}_{\mathrm{f}}<49.23\mathrm{eV}$ and $71.43<y<132.65$. Once fixed the values of the mass of the fermion $m_f$ and the interaction strength $y$, we tested the core-halo model with data from the Milky Way, local dwarf spheroidal galaxies and the SPARC database. We have found good agreement between the data and the core-halo models, varying only one free parameter: the central density. Thus a single fermion can fit hundreds of galaxies. Nevertheless, the dark matter halo surface density relation or the halo total mass and radius depend strongly on the model for the halo.

    hep-phastro-ph.GAPRD(2026)·0 citations
24. 24*

    Radiative decays of the ${\Sigma }_c$, ${\Xi }_c^{\prime }$ and ${\Omega }_c$ charmed baryons

    A. Dávila-Rivera🇲🇽 · H. García-Tecocoatzi🇲🇽 · A. Ramirez-Morales🇲🇽 · Ailier Rivero-Acosta🇲🇽 · E. Santopinto🇮🇹 · Carlos Alberto Vaquera-Araujo🇲🇽

    In this work, we study the radiative decays of the ${\Sigma }_c$, ${\Xi }_c^{\prime }$ and ${\Omega }_c$ charmed baryons, which belong to the flavor sextet ($6_{\mathrm{F}}$), within the constituent quark model formalism. The electromagnetic transitions are calculated from the ground and $P$-wave states to ground states, as well as from the second shell states to both the ground and $P$-wave final states. These decays play a crucial role in confirming the existence of certain resonances when strong decays are not allowed. Moreover, electromagnetic decay widths are particularly useful for identifying resonances when states have the same mass and total decay width. A relevant case is the ${\Omega }_c(3327)$ state, whose branching ratios between the strong decay channels are comparable; thus, the radiative decay widths may help assign this state. We also make the assignment of the recently discovered ${\Xi }_c^{\prime }(2923{)}^{+}$ baryon, which is consistent with being the isospin partner of the ${\Xi }_c^{\prime }(2923{)}^0$. This study presents, for the first time, the calculation of electromagnetic decays for $D_{\rho }$-wave states, $\rho -\lambda$ mixed states, and $\rho$-mode radially excited states in the charm sector. Throughout our calculations, we account for uncertainties arising from both experimental and model-dependent errors.

    hep-phPRD(2026)·3 citations
25. 25*

    A Thermal Relic Encyclopedia: Dark Matter Candidates Coupled to Quarks

    Dan Hooper🇺🇸 · Gordan Krnjaic🇺🇸 · Tanner Trickle🇺🇸 · Isaac R. Wang🇺🇸

    Thermal freeze-out is a compelling framework for naturally generating the dark matter abundance. We systematically study a broad range of dark matter and mediator particle combinations that can viably realize thermal freeze-out, focusing on models in which the mediator couples to Standard Model quarks. In each case, we calculate the relic density and consider existing constraints from accelerators, cosmology, direct detection, and indirect detection over the full range of dark matter and mediator masses. We present an encyclopedic catalog of matrix elements, cross sections, and decay rates which can be used as a reference for future studies of dark matter phenomenology.

    hep-phastro-ph.COhep-ex4 citations
26. 26*

    Muon collider probes of the gluonic quartic gauge couplings

    Yu-Chen Guo🇨🇳 · Peng-Cheng Lu🇨🇳 · Tong Arthur Wu🇺🇸

    We investigate the dimension-8 gluonic quartic gauge couplings (gQGCs) at future high-energy muon colliders through the process ${\mu }^{+}{\mu }^{-}\to gg\gamma$. Using detailed event simulation and optimized kinematic selections, we derive projected sensitivities to the Wilson coefficients and their associated new-physics scales, showing that muon colliders can probe deep into the multi-TeV regime and significantly surpass current LHC bounds. We further present the positivity bounds on those Wilson coefficients, as theoretical constraints from the fundamental principles of quantum field theory. Our results establish ${\mu }^{+}{\mu }^{-}\to gg\gamma$ as one of the most sensitive probes of dimension-8 new physics at future muon colliders.

    hep-phPRD(2026)·1 citation
27. 27*

    Heavy Long-lived Dark Vector Via a Gluonic Portal

    Xiaoyong Chu🇨🇳 · Qiyuan Gao🇨🇳 · Hongkai Liu🇺🇸 · Teng Ma🇨🇳 · Chengjie Yang🇨🇳

    We study a dark gauge boson $Z^{\prime }$ that exclusively couples to the QCD gluons through higher dimensional operators. These operators are generated from integrating out of heavy ultraviolet resonances carrying both QCD and dark gauge charges. With $SU(3{)}_C$ gauge invariance, charge and parity symmetries preserved, we find that the leading effective operators are restricted to have the form of $Z^{\prime }GGG$ and $Z^{\prime }{Z}^{\prime }GG$ at dimension-eight, which can naturally render the $Z^{\prime }$ particle long-lived, and serve as a viable dark matter candidate. We investigate the phenomenology of these operators with both collider experiments and cosmological observation, without and with the assumption that this dark gauge boson plays the role of the dominant dark matter component. For an unstable $Z^{\prime }$, we show that depending on its lifetime, it can be probed by various observables up to ultraviolet physics scale around $10^9$ GeV. For $Z^{\prime }$ being dark matter, we find that $m_{Z^{\prime }}\gtrsim 1$ TeV is consistent with the thermal freeze-out scenario. In contrast, in the freeze-in scenario, the extremely small couplings leave the relevant parameter space largely unconstrained by current experiments.

    hep-phJHEP(2026)·0 citations
28. 28*

    Neutron-deuteron scattering revisited with the EKM chiral nuclear force and the WPCD method

    Qing-Yu Zhai🇨🇳 · Dan-Yang Pang🇨🇳 · Wen-Di Chen🇨🇳 · O. A. Rubtsova🇷🇺 · Rui-Rui Xu🇨🇳 · Jun-Xu Lu🇨🇳 · Haozhao Liang🇯🇵 · Li-Sheng Geng🇨🇳

    We revisit the neutron-deuteron scattering using the Wave-Packet Continuum Discretization (WPCD) method with the EKM chiral nuclear force at various chiral orders. We rederive the permutation operator and solve the Faddeev-AGS equations directly, without rewriting the initial Faddeev kernel $t{G}_0$ and introducing pseudo-states, thereby rendering the approach easily extendable to a relativistic framework. We find that up to the next-to-next-to-next-to-leading order (N${}^3$LO), although one can well describe the differential cross sections, one cannot resolve the long-standing $A_y$ puzzle, consistent with previous studies. The fact that the N${}^3$LO chiral forces can well describe the $NN$ phase shifts and the results obtained with the EKM and Idaho N${}^3$LO chiral forces agree with each other underscores the need for further investigations to resolve the $A_y$ puzzle, e.g., considering three-body forces or relativistic effects.

    ↳ nucl-thhep-phnucl-exPRC(2026)·1 citation
29. 29*

    Non-vanishing non-linear Static Love Number of a Class of Extremal Reissner-Nordstrom Black Holes

    L.R. Gounis🇬🇷 · A. Kehagias🇬🇷 · G. Panagopoulos🇬🇷 · A. Riotto🇨🇭

    We compute the tidal Love numbers for a particular axially symmetric configuration of extremal Reissner-Nordstrom geometry. By exactly solving the non-linear Einstein equations, we investigate the tidal response of extremal Reissner-Nordstrom black holes in four-dimensional spacetimes under external gravitational fields. We show that, for the specific geometry considered, the static tidal Love number remains finite and non-vanishing to all orders in the external tidal field. By contrast, we verify that the Love number of an isolated extremal Reissner-Nordstrom black hole remains zero, in agreement with previous expectations. Furthermore, we explicitly calculate the Zerilli-Moncrief master functions and match them with the effective field theory description.

    ↳ gr-qchep-phhep-thJCAP(2026)·2 citations
30. 30*

    Excitation function of femtoscopic Lévy source parameters of pion pairs in EPOS4

    Yan Huang🇭🇺 · Matyas Molnar🇭🇺 · Daniel Kincses🇭🇺 · Mate Csanad🇭🇺

    Three-dimensional (3D) femtoscopic source parameters of pions provide a sensitive probe of the space-time structure of particle-emitting sources in high-energy heavy-ion collisions. Compared to one-dimensional measurements, three-dimensional femtoscopy not only provides a valuable cross-check but also offers a more complete characterization of the source geometry and its dynamical evolution. Particularly, differences between the out and side directions are sensitive to signals of a strong first-order phase transition, while the collision-energy dependence of Lévy radii may reveal non-monotonic features related to the equation of state. In this work, we systematically investigate the transverse mass (mT) and collision-energy (sqrt(sNN)) dependence of the three-dimensional femtoscopic parameters of pion pairs with Lévy-type sources in the STAR Beam Energy Scan (BES) range from sqrt(sNN) = 7.7 to 200 GeV using the EPOS4 model. The analyzed parameters include the Lévy index alpha, the correlation strength lambda, and the three-dimensional radii Rout, Rside and Rlong, corresponding to the outward, sideward, and longitudinal (beam) directions. Derived quantities such as the out-side squared radius difference and the out/side ratio are also investigated. The results show that the extracted radii Rside and Rlong decrease with increasing transverse mass and increase gradually with collision energy, while Rout shows little energy dependence. The Lévy index alpha exhibits only a mild dependence on mT and collision energy, whereas the correlation strength lambda shows a clear mT dependence and generally decreases with increasing collision energy. A comparison with EPOS3 results indicates general agreement within approximately 2sigma, with the notable exception of Rside, which is systematically smaller in EPOS4.

    ↳ nucl-thhep-phPLB(2026)·5 citations
31. 31*

    Thermoelectric coefficients of two-flavor quark matter from the Kubo formalism

    Harutyun Gabuzyan🇦🇲 · Arus Harutyunyan🇦🇲 · Armen Sedrakian🇩🇪

    The hot quark matter created in heavy-ion collision experiments can exhibit strong temperature and chemical-potential gradients, which in turn can generate electric fields through thermoelectric effects. In this work, we investigate two relevant thermoelectric coefficients -- the thermopower (Seebeck coefficient) and the Thomson coefficient -- of two-flavor quark matter using the Kubo formalism and the Nambu--Jona-Lasinio model as an effective description of dense, finite-temperature QCD. The required two-point equilibrium correlation functions are evaluated using the Matsubara formalism of thermal field theory, applying a 1/Nc expansion to the relevant multi-loop Feynman diagrams. We employ previously derived quark spectral functions obtained from one--meson-exchange diagrams above the Mott transition temperature. Our numerical results show that both thermoelectric coefficients increase approximately linearly with temperature and decrease with increasing chemical potential. We also estimate the magnitude of the electric fields that can be generated in heavy-ion collisions by thermal gradients via the Seebeck effect.

    ↳ nucl-thastro-ph.HEhep-phPRD(2026)·1 citation
32. 32*

    Evidence of Spin-Interference Effects in Exclusive $J/\psi \to e^{+}{e}^{-}$ Photoproduction in Ultraperipheral Heavy-Ion Collisions

    The STAR Collaboration

    We report the first evidence of spin interference in exclusive $J/\psi \to e^{+}{e}^{-}$ photoproduction in ultraperipheral heavy-ion collisions at STAR at $\sqrt{s_{NN}}=200$~GeV. In Au+Au collisions, a negative $\cos (2\varphi )$ modulation is found for $p_T<120$~MeV/$c$ with a significance of $3.2\sigma$, while the isobar data (Ru+Ru, Zr+Zr) show a consistent negative modulation with a significance of $1.9\sigma$, opposite in sign to that in ${\rho }^0\to {\pi }^{+}{\pi }^{-}$ photoproduction. This establishes for the first time that the interference sign is controlled by the spin structure of the final-state daughters, resolving the ambiguity present in the all-boson ${\rho }^0$ channel. The compact $J/\psi$ probes gluon distributions at perturbative scales, resulting in a weaker modulation and providing stringent constraints on Color Glass Condensate calculations. These findings demonstrate that spin-dependent interference in heavy vector mesons provides a new, experimentally accessible handle on gluon structure beyond traditional cross-section measurements.

    ↳ nucl-exhep-exhep-phnucl-thPRL(2026)·3 citations
33. 33*

    Singular $\alpha$-attractors

    Renata Kallosh🇺🇸 · Andrei Linde🇺🇸

    $\alpha$-attractor models naturally appear in supergravity with hyperbolic geometry. The simplest versions of $\alpha$-attractors, T- and E-models, originate from theories with non-singular potentials. In canonical variables, these potentials have a plateau that is approached exponentially fast at large values of the inflaton field $\phi$. In a closely related class of polynomial $\alpha$-attractors, or P-models, the potential is not singular, but its derivative is singular at the boundary. The resulting inflaton potential also has a plateau, but it is approached polynomially. In this paper, we will consider a more general class of potentials, which can be singular at the boundary of the moduli space, S-models. These potentials may have a short plateau, after which the potential may grow polynomially or exponentially at large values of the inflaton field. We will show that this class of models may provide a simple solution to the initial conditions problem for $\alpha$-attractors and may account for a very broad range of possible values of $n_s$ matching the recent ACT, SPT, and DESI data.

    ↳ hep-thastro-ph.COgr-qchep-phJCAP(2026)·10 citations
34. 34*

    Inferring black hole formation channels in GWTC-4.0 via parametric mass-spin correlations derived from first principles

    Emanuele Berti🇺🇸 · Francesco Crescimbeni🇮🇹 · Gabriele Franciolini🇨🇭 · Simone Mastrogiovanni🇮🇹 · Paolo Pani🇮🇹 · Grégoire Pierra🇮🇹

    We investigate the differences between several proposed formation scenarios for binary black holes (BBHs), including isolated stellar evolution, dynamical assembly in dense clusters and AGN disks, and primordial BHs. Our approach exploits the predicted spin features of each formation channel, and adopts parameterized models of the predicted correlations between the spin magnitudes (and orientations) and mass, inspired by first principles. Using hierarchical Bayesian inference on the recent GWTC-4.0 dataset, we compare these features across all models and assess how well each scenario explains the data. We find that the data strongly favor the presence of a positive correlation between mass and spin magnitude, in agreement with previous studies. Furthermore, the hierarchical scenario provides a better fit to the observations, due to the inclusion of second-generation mergers leading to higher spins at larger masses. The current dataset is not informative enough about spin orientation: the cluster (random orientations) and AGN (aligned orientations) scenarios have comparable Bayesian evidence. Finally, the mass-spin correlation predicted by the primordial scenario gives a poor fit to the data, and this scenario can only account for a subset of the observed events.

    ↳ gr-qcastro-ph.HEhep-phPRD(2026)·21 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.