Tue·Feb 17, 2026Tuesday·February 17, 2026

1. 01*

   Probing Rotational Dynamics of Quark Gluon Plasma via Global Vorticity

   Bhagyarathi Sahoo🇮🇳 · Captain R. Singh🇮🇳 · Raghunath Sahoo🇮🇳

   The findings on the spin polarization of $\Lambda$, $\Xi$, and $\Omega$ hyperons and spin alignment of $K^{\ast 0}$, $\varphi$, and $D^{\ast +}$ mesons in relativistic heavy-ion collision experiments at the RHIC and LHC facilities propose the emergence of a strong vorticity field produced in these collisions. Contemplating the potential impact of vorticity on the space-time evolution of deconfined QCD matter and its freeze-out properties, we aim to investigate its characteristics within the medium. We introduce a complementary and data-driven approach to quantify the global vorticity field by extracting it directly from the transverse momentum spectra of produced hadrons. Employing the experimental data for $\Lambda$, $\Xi$, $\Omega$, $K^{\ast 0}$, $K^{\ast \pm }$, $\varphi$, $\rho$, and $D^{\ast +}$ at mid-rapidity in Au+Au and Pb+Pb collisions over a wide range of beam energies, $\sqrt{s_{\mathrm{NN}}}=7.7$ GeV-5.02 TeV, and centrality classes, we systematically examine spin-vorticity coupling in the medium. Our finding on the magnitude of the extracted vorticity is consistent with values deduced from $\Lambda$ and $\bar{\Lambda }$ polarization measurements using statistical thermal models under the non-relativistic limit. Notably, we observe a prominent particle-species dependence of the vorticity, as well as a non-trivial variation with collision centrality and beam energy. These results indicate that vorticity-driven spin phenomena are sensitive to hadron structure and freeze-out dynamics, providing new constraints on the rotational properties of the QCD matter.

   hep-phhep-exhep-thnucl-ex+1PLB(2026)·0 citations
2. 02*

   Next-to-Leading-Order QCD Predictions for the $\Sigma$ Dirac Form Factors

   Bo-Xuan Shi🇨🇳 · Hui-Xin Yu🇨🇳 · Xue-Chen Zhao🇨🇳

   In this work, we compute the next-to-leading-order QCD corrections to the Dirac electromagnetic form factors of the $\Sigma$ hyperons within the hard-collinear factorization framework at leading power. The corresponding short-distance coefficient functions are extracted from the relevant seven-point partonic correlation functions. We find that the one-loop radiative corrections to the leading-twist hard-scattering contributions are numerically significant over a broad range of momentum transfer. Combining the perturbatively calculated hard kernels with nonperturbative $\Sigma$ distribution amplitudes determined from lattice QCD, we present state-of-the-art theoretical predictions for the $\Sigma$ hyperon electromagnetic form factors.

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

   The 95 GeV and 125 GeV Higgs Excesses in the Left-Right Supersymmetric Standard Model

   Zhi-Chuan Wang🇨🇳 · Jin-Lei Yang🇨🇳 · Qi-Zhen Qin🇨🇳 · Wen-Hui Zhang🇨🇳 · Tai-Fu Feng🇨🇳

   This study investigates the excesses observed around 95 GeV in diphoton and $b\bar{b}$ experiments within the framework of the Left-Right Supersymmetric Model (LRSSM). Considering the one-loop and two-loop effective potential corrections to the Higgs masses, the model is able to describe the experimentally observed $\mu (h_{95}{)}_{\gamma \gamma }$ and $\mu (h_{95}{)}_{b\bar{b}}$ signal strengths. In addition, we also present the impacts of the LRSSM-specific parameters $\tan {\beta }_R$, $v_R$ and $v_S$ on the theoretical predictions of the signal strengths for the 95 GeV and 125 GeV neutral Higgs both.

   hep-phPRD(2026)·1 citation
4. 04*

   Current status and prospects of light bino-higgsino dark matter in natural SUSY

   XinTian Wang🇨🇳 · Murat Abdughani🇨🇳

   Given recent advancements in dark matter (DM) search experiments, particularly the latest LUX-ZEPLIN (LZ) direct detection (DD) results, we systematically investigate the light bino--higgsino DM scenario within the natural supersymmetric framework. Requiring the electroweak fine-tuning parameter ${\Delta }_{\mathrm{EW}}<30$ fixes the higgsino mass parameter in the range of $|\mu |\in [100,350]$~GeV, while we extend the bino mass to $M_1\in [10,350]$~GeV. Incorporating constraints from Higgs physics, rare $B$ decays, LEP limits, and DD experiments, we find that part of the parameter space remains viable. However, the relic density of neutralino DM necessarily lies below the observed Planck value, contributing at most $\sim$2\% of the total DM abundance. Some of the surviving parameter space is already excluded by current 1\mbox{3 TeV LHC sear}ches, while the future 14 TeV HL-LHC with 3000 fb${}^{-1}$ luminosity will probe the remaining region of the considered parameter space.

   hep-ph1 citation
5. 05*

   Scale invariant radiative neutrino mass model

   Daijiro Suematsu🇯🇵

   We propose a scale invariant radiative neutrino mass model with custodial symmetry by introducing two real singlet scalars to the scotogenic model. Masses of an inert doublet scalar and right-handed neutrinos are induced by a vacuum expectation value (VEV) of a singlet scalar caused through the Coleman-Weinberg mechanism.It violates spontaneously both the custodial symmetry and the scale invariance. The weak scale can take a suppressed value compared with the singlet scalar VEV because of the custodial symmetry. In this framework we study phenomenological consequences for neutrino mass, dark matter and baryon number asymmetry by assuming a texture for neutrino Yukawa couplings. Since the required dark matter abundance cannot be explained by a neutral component of the inert doublet scalar in that case, the lightest right-handed neutrino should be dark matter. Mass of the dark matter is predicted to be less than $O(1)$ MeV and baryon number asymmetry could be explained through resonant leptogenesis.

   hep-phPRD(2026)·0 citations
6. 06*

   An imprint of intrinsic quark--gluon correlations: a nonmonotonic feature in $e(x)$

   Chao Shi🇨🇳 · Liming Lu🇨🇳 · Ian Cloët🇺🇸 · Wenbao Jia🇨🇳 · Peter Tandy🇺🇸

   We present the first rainbow-ladder Dyson-Schwinger equations study of the pion's chiral-odd, twist-3 parton distribution $e_{\mathrm{q}}(x)$. By deriving a novel Dyson-Schwinger equation for the pion's quark-quark correlation matrix, we simultaneously extract from it both the unpolarized twist-2 parton distribution function $f_{\mathrm{q}}(x)$ and the twist-3 distribution $e_{\mathrm{q}}(x)$. Our results show that chiral symmetry strongly suppresses the twist-2 component of $e_{\mathrm{q}}(x)$, leaving the genuine twist-3 quark-gluon component dominant and featuring a node. We therefore argue that the genuine twist-3 term can make a substantial contribution to hadronic $e(x)$, producing a nonmonotonic structure that is a clear imprint of intrinsic quark-gluon correlations. We point out that the existence of a hump-like feature is compatible with, although not uniquely indicated by, recent proton extractions and awaits more precise determination.

   hep-phPRD(2026)·3 citations
7. 07*

   Factorization formula connecting the ${\Lambda }_Q$ LCDA in QCD and boosted HQET

   Yu-Ji Shi🇨🇳 · Jun Zeng🇨🇳

   Light-cone distribution amplitudes (LCDAs) are essential to precision phenomenology in heavy baryon decays. In this work, we derive a factorization formula connecting the leading-twist QCD LCDA to the boosted HQET LCDA of the ${\Lambda }_Q$ baryon in the peak region. We demonstrate a significant simplification of the matching procedure by applying the method-of-regions to perturbative calculations. With this simplification, we calculate the required one-loop perturbative corrections to the QCD and boosted HQET LCDAs in the $\overline{\mathrm{MS}}$ scheme, and thereby obtain the one-loop jet function that serves as the matching kernel in the factorization formula. This result provides a critical step toward lattice QCD calculation of heavy baryon LCDAs in the future.

   hep-phhep-latJHEP(2026)·4 citations
8. 08*

   Limits on the Carroll-Field-Jackiw electrodynamics from geomagnetic data

   G. F. de Carvalho🇧🇷 · M. Fillion🇫🇷 · P. C. Malta🇧🇷 · C. A. D. Zarro🇧🇷

   Lorentz-symmetry violation may be described via the CPT-odd, dimension-3, Carroll-Field-Jackiw term, which couples the electromagnetic fields to a constant 4-vector $k_{\mathrm{AF}}$ selecting a preferred direction in spacetime. We solve the field equations using the Green's method for a static point-like magnetic dipole and find the $k_{\mathrm{AF}}$-dependent corrections to the standard dipolar magnetic field that strongly dominates the near-Earth magnetic field. Given the very good agreement between current models and ground- and satellite-based geomagnetic data, our strongest constraints on the components of $k_{\mathrm{AF}}$ in the Sun-centered frame read $|(k_{\mathrm{AF}}{)}_Z|\lesssim 4\times 10^{-25}\mathrm{GeV}$ for $|(k_{\mathrm{AF}}{)}_X|,|(k_{\mathrm{AF}}{)}_Y|\lesssim 10^{-24}\mathrm{GeV}$ at the two-sigma level. This represents an improvement of about four orders of magnitude over earlier bounds based on other geophysical phenomena.

   hep-phphysics.geo-phJHEP(2026)·0 citations
9. 09*

   Measuring neutrino mixing above 1 TeV with astrophysical neutrinos

   Mauricio Bustamante🇩🇰 · Qinrui Liu🇨🇦 · Gabriela Barenboim🇪🇸

   We assess the potential for measuring neutrino mixing parameters at energies above 1~TeV, for the first time, using the flavor composition of TeV--PeV astrophysical neutrinos, i.e., the proportion of ${\nu }_e$, ${\nu }_{\mu }$, and ${\nu }_{\tau }$. Today, flavor measurements inferred from the 11.4-year IceCube Medium Energy Starting Events sample are insufficient to constrain the mixing parameters due to limited statistics, challenges in flavor identification, and uncertainty in neutrino production. Yet, upcoming multi-neutrino-telescope observations -- even using only existing telescopes -- may achieve sensitivity to ${\theta }_{23}$ and ${\theta }_{13}$ when combined with traditional oscillation experiments. We establish the current status and future prospects for testing the three-flavor mixing framework in the previously unexplored TeV--PeV regime and quantify the minimum detectable size of flavor-modifying beyond-Standard-Model effects, providing a roadmap for high-energy neutrino mixing measurements.

   hep-phastro-ph.HEhep-ex3 citations
10. 10*

    Search for Cosmic-Ray Produced Dark Meson via the $U(1{)}_{\text{D}}$ Portal at JUNO

    Zirong Chen🇨🇳 · Dan Chi🇨🇳 · Jinmian Li🇨🇳 · Junle Pei🇨🇳

    We investigate the atmospheric production and subsequent detection of sub-GeV dark mesons within the framework of a confining dark sector coupled to the Standard Model (SM) via a $U(1{)}_{\text{D}}$ vector portal. High-energy cosmic ray interactions in the atmosphere produce dark quarks through proton bremsstrahlung, rare decays of Standard Model mesons, and Drell-Yan processes, which subsequently hadronize into dark mesons. We adopt a modified Quark Combination Model to describe the non-perturbative dark hadronization process, allowing for a detailed event-level characterization of the dark meson flux. We simulate the flux and the interactions of these relativistic dark mesons in the Jiangmen Underground Neutrino Observatory (JUNO) using the GENIE generator, considering both elastic scattering off nuclei and deep inelastic scattering channels. Adopting a LES-inspired conservative signal definition with $15\mathrm{MeV}<E_{\mathrm{vis}}<100\mathrm{MeV}$ and vetoing events containing final-state neutrons, we derive projected $90\%$ C.L. sensitivities to the coupling strength between the dark gauge boson and the SM sector for a $20\mathrm{kton}\cdot \mathrm{year}$ exposure. For the representative benchmark masses $m_{Z^{\prime }}=0.001$, $0.01$, and $0.1\mathrm{GeV}$, the projected JUNO reach corresponds to $g_{\mathrm{SM}}^{90}=6.48\times 10^{-5}$, $7.75\times 10^{-5}$, and $2.37\times 10^{-4}$, respectively. This reach is found to be only mildly sensitive to order-one variations of the hadronization parameter, as illustrated by the choices ${\kappa }_{\beta }=1/3,1,$ and $3$.

    hep-phPRD(2026)·1 citation
11. 11*

    Maxwell theories along the light track: Null Formalism in extended electrodynamics

    Zhi Xiao🇨🇳 · Bing Sun🇨🇳 · Tao Zhu🇨🇳

    We develop a differential-form approach to systematically derive the Newman-Penrose null-tetrad equations for Lorentz-violating extensions of Maxwell electrodynamics. The coordinate-independent nature of differential forms allows the actions and corresponding field equations of the theory to be expressed compactly and enables a systematic and transparent derivation of first-order equations in the Newman-Penrose formalism. Within this formalism, we explicitly present a simple algebraic construction for the gauge invariant extended Maxwell actions that avoids explicit index manipulations up to mass dimension six. The combined scheme of differential-form approach and Newman-Penrose formalism offers an efficient tool for analyzing Lorentz-violating effects on asymptotic photon propagation and polarization.

    hep-ph0 citations
12. 12*

    Establishing the Primary HEFT as a Precision Benchmark for UV-HEFT Matching

    Zizhou Ge🇨🇳 · Huayang Song🇰🇷 · Xia Wan🇨🇳

    We match the real Higgs triplet model (RHTM) onto HEFT under different parameter choices and power-counting schemes, thereby obtaining several representative HEFT formulations and clarifying their relations. We establish the primary HEFT (pHEFT) as a benchmark framework, demonstrating that alternative HEFT constructions can be systematically derived from it. A key advantage of the pHEFT construction is its parameter choice, which maintains linear relations between the UV Lagrangian parameters and squared heavy masses. By strictly employing the inverse squared heavy masses as the expansion parameters without imposing additional constraints, pHEFT preserves maximal ultraviolet (UV) information and ensures higher perturbative accuracy by avoiding the additional truncations inherent in more complex, non-linear formulations or extra constraints. Through the analysis of the $Z_2$-symmetric real singlet model and the 2HDM, we illustrate the criteria for identifying viable primary HEFT constructions in UV models with scalar extensions. Furthermore, for the first time, we derive the HEFT operators of the RHTM involving fermions.

    hep-phPRD(2026)·3 citations
13. 13*

    Flavor dependence of chiral symmetry breaking and the conformal window

    Yi-huai Chen🇨🇳 · Yi Lu🇨🇳 · Zhi-wei Wang🇨🇳 · Yu-xin Liu🇨🇳 · Fei Gao🇨🇳

    We investigate the phase structure of Quantum Chromodynamics (QCD) in the vacuum as a function of quark flavor number $N_f$ within the chiral limit. By self-consistently solving the coupled DSEs for the quark and gluon propagators in a minimal QCD scheme, we elucidate the nonperturbative dynamics governing dynamical chiral symmetry breaking. Our calculations determine a critical flavor number of $N_f^c=6.81$ which marks the chiral symmetry restoration of quarks. Further analysis reveals the critical exponents of the chiral condensate as $-⟨\bar{\psi }\psi ⟩\sim |N_f-N_f^c{|}^{0.53(9)}$, characterized the second order feature of this phase transition of chiral symmetry. Additionally, we discuss the implications for the walking regime towards the conformal window at larger flavor.

    hep-phhep-lathep-thPRD(2026)·2 citations
14. 14*

    Rephasing invariant structure of CP phase for simplified mixing matrices in Fritzsch--Xing parametrization

    Masaki J. S. Yang🇯🇵

    In this paper, we construct an explicit rephasing transformation that converts an arbitrary unitary mixing matrix into the Fritzsch--Xing (FX) parametrization, which is obtained by trivializing arguments of the matrix elements in the third row and third column. We further analyze rephasing invariant structure of the FX phase ${\delta }_{\mathrm{FX}}$ under an approximation $U_{13}^e=0$, where the 1-3 element of the diagonalization matrix of charged leptons $U^e$ is neglected. With an additional approximation $U_{23}^e=0$, the FX phase becomes highly simplified, reducing to a sum of the neutrino-intrinsic FX phase ${\delta }_{\mathrm{FX}}^{\nu }$ and the contribution from the relative phase ${\rho }_1^{\prime }-{\rho }_2^{\prime }$ between the lighter 1-2 generations. The phase ${\delta }_{\mathrm{FX}}$ for finite $U_{23}^e$ is understood as a generalization of the compact expression. This result covers almost all perturbative calculations of CP phases for the CKM and MNS matrices with hierarchical charged fermions.

    hep-phNPB(2026)·3 citations
15. 15*

    Dominant One-Loop Seesaw Contribution Induced by Non-Invertible Fusion Algebra

    Monal Kashav🇮🇳

    The topological classification of the one-loop Weinberg operator at dimension-5 enables a systematic categorization of radiative neutrino mass models. Among these, the category consisting loop-extended seesaw frameworks is theoretically appealing but conventional discrete or continuous symmetries (\emph{e.g.}, $U(1)$ or ${\mathbb{Z}}_M$) cannot genuinely forbid the corresponding tree-level contributions, making loop dominance difficult to realize. We show that \textit{non-invertible selection rules} (NISRs) naturally enforce the absence of tree-level terms while ensuring a dominant one-loop contribution. Intriguingly, the same non-invertible structure also stabilizes the dark matter candidate, providing a unified radiative origin of neutrino mass and dark sector stability. In particular, we focus on the T4-2-$i$ topology which embodies a type-II one-loop seesaw and demonstrate its natural realization from $Z_7$ Tambara--Yamagami (TY) fusion algebra.

    hep-ph3 citations
16. 16*

    Revisiting charmonium hybrid spectroscopy

    Ri-Qing Qian🇨🇳 · Bing Chen🇨🇳 · Xiang Liu🇨🇳

    Hadrons with explicit gluonic degrees of freedom, such as charmonium hybrids, are key to understanding nonperturbative behavior of strong interaction, yet they remain experimentally elusive. Within a constituent gluon model treating the hybrid as a $c\bar{c}g$ three-body system with a transverse electric gluon, we predict the masses of the lightest hybrid multiplet ($J^{PC}=1^{--},0^{-+},1^{-+},2^{-+}$) to lie in the range $4.19$--$4.32$ GeV. By analyzing their decay patterns, we provide specific, experimentally testable signatures to guide the search for these exotic states at current and future facilities.

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

    Dark higher-form fields and triangle anomalies

    Cypris Plantier🇫🇷 · Christopher Smith🇫🇷

    Light scalar and vector particles admit non-trivial descriptions in terms of anti-symmetric higher-rank tensor fields. Far from mere rewritings, these provide compelling alternative frameworks, leading to immediate phenomenological applications. In this paper, we extend the playground to include the contributions of fermionic triangle loops, and use these results to compare the standard and higher-form realizations for two phenomenological processes: the pair production of two dark particles and the decay of a dark particle in two photons. Though they all do show some dependencies on the chosen realizations for the spin-zero or the spin-one dark states, we find that the two-photon mode is particularly sensitive and could actually be our prime window into the true nature of the dark field.

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

    Gauge-independent gravitational waves from a minimal dark $U(1)$ sector with viable dark matter candidates

    Wan-Zhe Feng🇨🇳 · Zi-Hui Zhang🇨🇳

    Searches for stochastic gravitational wave backgrounds generated by first-order phase transitions offer a powerful probe of hidden sectors, but quantitative predictions in gauge theories are obstructed by the gauge dependence of the finite-temperature effective potential and the associated tunneling action. We study a minimal gauged $U(1)$ dark sector containing a dark Higgs and a dark photon, optionally supplemented by a vectorlike dark fermion, coupled to the Standard Model through the Higgs portal or kinetic mixing. Using the Nielsen identity together with a controlled derivative expansion and power counting, we construct a gauge-independent effective action in the high- and low-temperature limits, enabling model-intrinsic nucleation dynamics and robust gravitational wave predictions. We perform dedicated Monte Carlo scans in both limits and map viable microscopic parameters to detector-facing peak frequencies and amplitudes, spanning bands relevant to pulsar timing arrays and planned space-based interferometers. In our scans, supercooled phase transitions typically produce much stronger signals and are more likely to fall within the sensitivity range of current and future gravitational wave detectors, whereas parametrically high-temperature phase transitions generally yield weaker signals. We further connect the phase transition phenomenology to viable dark matter candidates within the same minimal field content, providing benchmark targets for dark photon dark matter and dark fermion dark matter, and highlighting their complementarity with gravitational wave observables. Overall, our results provide an end-to-end, gauge-independent pipeline from a minimal hidden sector Lagrangian to gravitational wave spectra and cosmologically viable dark matter benchmarks, yielding the most reliable and concrete predictions to date for a minimal gauged $U(1)$ dark sector.

    hep-phastro-ph.HE5 citations
19. 19*

    Parapositronium decay into three photons and implications for the neutral pion

    Andrzej Czarnecki🇨🇦 · Divyesh Dagia🇨🇦 · Ting Gao🇺🇸 · Ripanjeet Toor🇨🇦

    We complete the determination of the parapositronium decay into three photons by evaluating amplitudes mediated by the $Z$ boson. We show that, contrary to the expectation that the extra mass scale $m_e$ may bring an enhancement to the overall scaling, the amplitude turns out to start at $1/m_Z^6$ order, similarly to the $W$ boson mediated amplitude. The decay rate with both $W$ and $Z$ boson contributions is found to be $1.1\cdot 10^{-80}$ eV, about 47 orders of magnitude smaller than previously estimated. We also discuss its implication for the ${\pi }^0\to 3\gamma$ amplitude.

    hep-phPRD(2026)·2 citations
20. 20*

    Strange Quark Electric Dipole Moment withTopological Anomalies

    Chao-Qiang Geng🇨🇳 · Xiang-Nan Jin🇨🇳 · Chia-Wei Liu🇨🇳 · Bin Wu🇨🇳

    We introduce an anomaly-based framework to probe quark electric dipole moments in exclusive hadronic final states produced in $e^{+}{e}^{-}$ annihilation. Chern-Simons-induced anomalous couplings yield a clean T-odd asymmetry $A_T$ from interference between the Standard-Model amplitude and dipole-moment contributions. As an application, ${\gamma }^{\ast }\to K^{+}{K}^{-}{\pi }^0$ provides direct sensitivity to the strange-quark EDM $d_s$ in the chiral limit. The precision on $d_s$ can reach $\mathcal{O}(10^{-16})e\cdot \mathrm{cm}$ with existing CMD--3 data and $\mathcal{O}(10^{-18})e\cdot \mathrm{cm}$ using current $J/\psi$ samples at BESIII, improving the current direct constraint from hyperon EDM by two to three orders.

    hep-phhep-exPRD(2026)·0 citations
21. 21*

    Inclusive hadroproduction of ${\chi }_{c1}(3872)$, $X_b$ and pentaquarks

    Nora Brambilla🇩🇪 · Mathias Butenschoen🇩🇪 · Simon Hibler🇩🇪 · Abhishek Mohapatra🇩🇪 · Antonio Vairo🇩🇪 · Xiangpeng Wang🇨🇳

    We use the Born--Oppenheimer effective field theory factorization to compute the inclusive production cross sections of the ${\chi }_{c1}(3872)$ and its partner in the bottomonium sector. In the same framework, we compute the production cross sections of the pentaquark states $P_{c\bar{c}}(4312{)}^{+}$, $P_{c\bar{c}}(4457{)}^{+}$, $P_{c\bar{c}}(4380{)}^{+}$ and $P_{c\bar{c}}(4440{)}^{+}$ within two possible scenarios for the Born--Oppenheimer potentials. Also for pentaquarks, we extend the results to the bottomonium sector. All our results are genuine predictions that do not involve fits to prompt hadroproduction data.

    hep-phhep-exnucl-thJHEP(2026)·9 citations
22. 22*

    Complementarity of di-top and four-top searches in interpreting possible signals of new physics

    Henning Bahl🇩🇪 · Philipp Gadow🇩🇪 · Romal Kumar🇩🇪 · Krisztian Peters🇩🇪 · Panagiotis Stylianou🇨🇾 · Georg Weiglein🇩🇪

    Final states comprising two or more top quarks are important search channels at the Large Hadron Collider for scalar particles predicted in models of physics beyond the Standard Model. While the di-top final state profits from a higher signal cross section, it can be subject to intricate interference patterns. Besides the interference with the large QCD background, in case of the presence of more than one high-mass scalar also large signal--signal interference contributions can occur. We show that in such scenarios it is crucial to account for loop-level mixing for obtaining accurate exclusion bounds. We demonstrate how the interference patterns can obscure the interpretation of possible deviations from the Standard Model expectations. We show that the four-top final state, while giving rise to a smaller signal cross section, provides important complementary information due to its much smaller signal--background interference contributions. Thus, the results obtained from the four-top final state can be instrumental for pinpointing the underlying new physics scenario.

    hep-ph2 citations
23. 23*

    Thermal Bhabha scattering under the influence of non-hermiticity effects

    D. S. Cabral🇧🇷 · A. F. Santos🇧🇷 · R. Bufalo🇧🇷

    In this paper, we investigate the Bhabha scattering process within the framework of non-Hermitian QED at finite temperature. In this theory, the hermiticity condition, typically required in quantum field theory to ensure the reality of physical observables, is replaced by the condition of unbroken $PT$-symmetry which favors the introduction of an axial mass and a vector-axial gauge coupling. Using the Thermofield Dynamics formalism, we derive and comprehensively analyze the thermal differential cross section for the Bhabha scattering. Furthermore, we explore the high-energy limit of the scattering amplitude and establish constraints upon the axial coupling constant, offering valuable insights into the system's behavior under extreme conditions.

    hep-phhep-thJ.Subatomic Part.Cosmol.(2026)·0 citations
24. 24*

    Dispersive analysis of the $\mathbf{\varphi }\to \mathbf{\gamma }{\mathbf{\pi }}^0{\mathbf{\pi }}^0$ process

    Bai-Long Hoid🇩🇪 · Igor Danilkin🇩🇪 · Marc Vanderhaeghen🇩🇪

    We present an analysis of the radiative decay $\varphi \to \gamma {\pi }^0{\pi }^0$ in a dispersive framework, where the two-pion subsystem undergoes strong final-state interactions that cover the $f_0(500)$ and $f_0(980)$ regions. We employ a coupled-channel Muskhelishvili-Omnès framework that allows for a consistent treatment of two scalar resonances and crossed-channel singularities induced by the Born and vector-meson exchanges. We explicitly verify the equivalence between the modified and standard Muskhelishvili-Omnès representations for vector-meson pole contributions when the isoscalar Omnès matrix is chosen asymptotically bounded, and we adopt the standard representation in decay kinematics. This yields, for the first time, a parameter-free dispersive prediction for the kaon Born rescattering, which provides a dominant contribution. To obtain a good fit to the KLOE and SND data, we employ a once-subtracted coupled-channel dispersion relation with heavier left-hand cut contributions and two unknown subtraction constants. The results demonstrate the consistency among the data for $\pi \pi$ scattering, $\gamma \gamma$ fusion, and $\varphi$ radiative decay, thereby validating the underlying dispersive formalism and the input used for the hadronic Omnès matrix and left-hand cuts.

    hep-phhep-exnucl-thPRD(2026)·1 citation
25. 25*

    The Sun Can Strongly Constrain Spin-Dependent Dark Matter Nucleon Scattering Below the Evaporation Limit

    Thong T.Q. Nguyen🇸🇪 · Tim Linden🇸🇪

    The Sun is a promising target for dark matter (DM) searches due to its ability to accumulate DM particles via scattering and catalyze their self-annihilation. However, at low DM masses, DM particles can also "evaporate" due to subsequent collisions with the hot thermal plasma of the Sun. While several modeling studies have calculated the competitive dynamics of DM evaporation and annihilation, observational studies have typically assumed a fixed 4 GeV "evaporation limit", below which DM evaporates before it can annihilate. In this paper, we consider the competitive effects of DM evaporation and annihilation on spin-dependent DM nucleon cross-section limits, finding that Solar observations can continue to exceed terrestrial constraints by between 1-5 orders of magnitude for DM masses between 2-4 GeV, and can even provide world leading constraints below 0.2 GeV where direct detection is limited.

    hep-phastro-ph.HE7 citations
26. 26*

    Excluding MeV-scale QCD axions by $K_L\to {\pi }^0{\pi }^{0}a$ at KTeV

    Takaya Iwai🇯🇵 · Ryosuke Sato🇯🇵 · Kohsaku Tobioka🇺🇸 · Takumu Yamanaka🇯🇵

    An interesting proposal suggests that a QCD axion $(a)$ coupling to the up quark, down quark, and electron remains viable for an axion mass near 10~MeV. In this paper, this possibility is reexamined by deriving new bounds from kaon decays. In particular, we perform a detailed analysis of the $K_L\to {\pi }^0{\pi }^0{e}^{+}{e}^{-}$ measurement reported by the KTeV experiment, and reinterpret $K^{+}$ decay measurements at the E949 and NA62 experiments to constrain both the diphoton decay and effectively invisible decay modes of the axion. We find that, combined with the previously known bounds, the viable window for the MeV-scale QCD axion is excluded, primarily due to the KTeV bound. Uncertainties associated with the chiral Lagrangian are further examined, and the scenario remains excluded even after accounting for these uncertainties, except for a tiny region of parameter space where higher-order corrections must finely cancel the leading-order contribution, suppressing the branching ratio of $K_L\to {\pi }^0{\pi }^{0}a$ by three orders of magnitude.

    hep-phhep-ex1 citation
27. 27*

    Decoherence, Perturbations and Symmetry in Lindblad Dynamics -- Implications for Diffractive Dissociation

    A.Y.Klimenko🇷🇺

    We extend a perturbative Dyson-type treatment and discrete-symmetry constraints from the Schrödinger and von Neumann equations to a dephasing Lindblad framework. This work develops further the odd-symmetric formulation involving dual temporal conditions from general dynamical considerations to specific tools of quantum mechanics. Applying the resulting scaling relations to published single- and double-diffractive data in $pp$ and $p\bar{p}$ collisions (ISR, UA4, UA5, CDF, D0, ALICE, and E710), we show that single-diffraction cross sections are well described by a three-parameter fit with a relative RMS deviation of $\sim 4\%$, substantially improving upon conventional approximations that neglect decoherence. The extracted decoherence factor is consistently $\varphi \approx 0.89$, in agreement across SD, DD, and E710-based (direct) estimates, and is naturally interpreted as $\varphi =1$ for CP-invariant dephasing but $\varphi <1$ for CPT-invariant dephasing, favouring the latter.

    ↳ quant-phhep-phEPJC(2026)·1 citation
28. 28*

    Quarkyonic matter and hadron-quark crossover from an ultracold atom perspective

    Hiroyuki Tajima🇯🇵 · Kei Iida🇯🇵 · Toru Kojo🇯🇵 · Haozhao Liang🇯🇵

    The dense matter equation of state is of great interest due to the recent development of astrophysical observations for neutron stars. A rapid increase in pressure indicates a continuous crossover from a hadron phase to a quark phase without any phase transitions, yet its microscopic mechanism remains elusive. Recently, a peak in the speed of sound and a baryon momentum-shell structure, which are predicted from a quarkyonic matter picture, have been regarded as key features of the hadron-quark crossover. In this work, we explore a field-theoretical framework to describe the hadron-quark crossover, drawing an analogy with the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer (BEC-BCS) crossover established in ultracold atomic experiments. Strikingly, a peak in the speed of sound and the baryon momentum-shell structure can simultaneously be explained by the tripling fluctuation effect arising from a different context of quantum many-body physics. We demonstrate these properties in a simplified model and provide a microscopic derivation of the quarkyonic matter model within our field-theoretical framework.

    ↳ nucl-thastro-ph.HEcond-mat.quant-gascond-mat.supr-con+1Class.Quant.Grav.(2026)·1 citation
29. 29*

    Resummation of small-spin singularities in anomalous dimensions of twist-two operators

    Alexander N. Manashov🇩🇪 · Sven-Olaf Moch🇩🇪 · Leonid A. Shumilov🇩🇪

    Anomalous dimensions of leading-twist operators in QCD play an important role in precision predictions for high-energy processes, since they govern the scale evolution of parton distributions. Their analytic structure as a function of spin is particularly important due to the complexity of higher-loop computations. In these proceedings, we discuss the resummation of the certain type of such singularities that share common features with those appearing in the quark flavor-nonsinglet sector of QCD. Our main focus is on the interplay between Gross-Neveu-Yukawa model in $ϵ$ expansion and Gross-Neveu in $1/N$ expansion. Such resummation allows one to predict the higher-loop singular behavior and reveals connections with the conformal Regge theory and recent studies of detector operators in QCD and various conformal field theories.

    ↳ hep-thhep-ph1 citation
30. 30*

    PeV neutrons as origin of separated SS433 TeV signals

    D. Fargion🇮🇹 · P.G. De Sanctis Lucentini🇷🇺 · S. Turriziani · M.Y. Khlopov🇫🇷 · D. Sopin

    The SS433, a well-known binary system with an internal black hole, have shown since half a century, an inner (a few year light distances) twin precessing jets spirals. These beams are made by tidal forces while stripping mass from large stellar companion feeding an inner BH accretion disk and an orthogonal accelerating twin jet. From it, the radio, X gamma jet emission. A couple of years ago H.E.S.S telescope as well as HAWC and LHAASO array detectors, discovered also the surprising signature of an unexpected far twin separated gamma beam at tens TeV energy. At a hundred light years distances from its central source. We suggest that it is the legacy of a past rare eruption, a century ago, of tens PeV (10^16 eV) relativistic twin neutron beams. Their beta decay in flight at far distances, into proton, neutrino and in particular into tens TeV electrons, could feed the observed TeV gamma traces. They are originated by the same secondary tens TeV electrons emitting hard gamma, by Inverse Compton Scattering onto interstellar infrared photons.

    ↳ astro-ph.HEastro-ph.GAhep-phhep-thPoS(2025)·0 citations
31. 31*

    The initial states of high frequency gravitons

    Massimo Giovannini🇨🇭

    After distinguishing the role of classical and quantum inhomogeneities in cosmological backgrounds, we constrain the initial states of the relic gravitons as soon as the different wavelengths of the spectrum cross the comoving Hubble radius, without any reference to earlier timescales. According to this pragmatic perspective the quantum states with finite energy density at the crossing time consistently affect the two-point functions and the related power spectra. An initial state different from the vacuum turns out to be marginally permitted in the low frequency range (associated with the largest observable wavelengths that crossed the comoving Hubble radius) while the intermediate and high frequency domains of the spectrum are populated by the gravitons produced from the vacuum. The non classical correlations are expected to dominate between the kHz and the THz since in this region gravitons are produced quantum mechanically with a negligible contribution from the initial state.

    ↳ gr-qcastro-ph.COhep-phhep-th0 citations
32. 32*

    Accessing the Gluon Momentum Fraction of Nucleons through the Gradient Flow

    Robert Edwards🇺🇸 · Joe Karpie🇺🇸 · Lorenzo Maio🇮🇹 · Christopher J. Monahan🇺🇸 · Kostas Orginos🇺🇸 · David Richards🇺🇸 · Alexandru M. Sturzu🇺🇸 · Savvas Zafeiropoulos🇫🇷

    We calculate the gluon momentum fraction of the nucleon using lattice quantum chromodynamics (QCD), with a nonperturbative renormalization technique based on the gradient flow. The gluon momentum fraction is determined on a single Wilson-clover ensemble using Nf = 2+1 flavors with pion mass 358 MeV and lattice spacing 0.094 fm. We employ the variational method to reduce excited-state contamination and apply the distillation framework to ensure a large operator basis. To reduce systematic uncertainties, we apply Bayesian model averaging to all fit procedures. We apply matching coefficients to the flow-time dependent lattice results to recover the gluon momentum fraction in the MS-scheme at 2 GeV. Our final result is <x>_g(\mu = 2 GeV) = 0.482(35), where we quote only statistical uncertainties.

    ↳ hep-lathep-phPRD(2026)·3 citations
33. 33*

    Gravitational waves from supercooled phase transitions and pulsar timing array signals

    Jinzheng Li🇺🇸 · Pran Nath🇺🇸

    The recent detection of a gravitational wave background in the nano-Hertz frequency range by Pulsar Timing Array (PTA) collaborations, including NANOGrav, EPTA, and PPTA, has opened a new avenue for exploring fundamental physics in the early universe. In this work, we analyze a supercooled first-order phase transition in a hidden sector with a spontaneously broken $U(1{)}_X$ gauge symmetry as a source for this signal. We demonstrate that the thermal history of the hidden and visible sectors plays a crucial role in the gravitational wave power spectrum analysis. Our analysis shows that supercooled phase transitions can generate gravitational waves strong enough to explain the PTA observations while satisfying cosmological constraints from Big Bang Nucleosynthesis.

    ↳ astro-ph.COhep-ph2 citations
34. 34*

    Effects of the symmetry energy slope on magnetized neutron stars

    Luiz L. Lopes🇧🇷 · Cesar V. Flores🇧🇷 · Débora P. Menezes🇧🇷

    In this work, we study the effect of the symmetry slope on the observables of weakly and strongly magnetized neutron stars within the chaotic magnetic field approximation. We investigate the impact of the symmetry energy slope in the equation of state, as well as on the observables of neutron stars, by calculating their masses, radii, redshifts, tidal deformabilities, and fundamental-mode gravitational-wave frequencies. We show that the effect of the magnetic field is strong on low mass stars, producing a softer equation of state and correspondingly lower values of radii. Furthermore, the magnetic field also causes a significant drop in the dimensionless tidal parameter even when the effects on the radii are small. At the end of the paper, we discuss the effects of the magnetic field in neutron stars' universal relations.

    ↳ astro-ph.HEgr-qchep-phnucl-thUniverse(2026)·0 citations
35. 35*

    Quintessence with tachyonic resonance and late-time cosmic-microwave-background and gravitational-wave signals

    Shun Yoshioka🇯🇵 · Kiyotomo Ichiki🇯🇵 · Yuichiro Tada🇯🇵 · Takahiro Terada🇯🇵

    Combinations of recent cosmological observations, including Dark Energy Spectroscopic Instrument (DESI), show hints of a dynamical nature for dark energy. While the data suggest the possibility of the phantom crossing, it is worth thoroughly exploring quintessence models. Given that phenomenological parametrisations of the equation-of-state parameter $w(a)$ with a sharp transitional feature fit the data well, we study the realisation of such models in quintessence. In the late Universe, the quintessence field begins to oscillate abruptly, changing the behaviour of $w$. Naturally, such a model entails tachyonic instability, and particle production modifies $w$. We perform numerical lattice simulations to study the time dependence of $w$. In addition, the violent particle production produces significant density perturbations and the stochastic gravitational-wave background, whose characteristic scale depends on the mass scale of the quintessence around the minimum of the potential. We discuss the observability of these late-time cosmological signals through cosmic microwave background, quasar astrometry, pulsar timing arrays, and other observational probes.

    ↳ astro-ph.COgr-qchep-ph1 citation
36. 36*

    Human versus Artificial Intelligence; various significant examples in astrophysics

    A. De Rújula🇪🇸

    In a recent arXiv posting [1] I reported the result of an experiment: asking Perplexity.ai to compare three items concerning (ordinary) Gamma Ray Burts (GRBs): the data, the standard paradigm(s) and the "Cannonball" (CB) model. Here I ask the same URL to extend this comparison to long--lasting GRBs, binary Neutron-Star mergers and their associated short--hard GRBs, low--luminosity GRBs, X--ray flashes, X--ray transients, and non--solar cosmic rays. The results of this experiment are enlightening but worrisome. Except for this abstract, two footnotes and two other references to standard [2] and CB-model [3] articles and talks, all of what follows is, verbatim, what the cited AI "opines".

    ↳ astro-ph.HEhep-phphysics.soc-ph0 citations
37. 37*

    The road of quantum entanglement: from Einstein to 2022 Nobel Prize in Physics

    Yu Shi🇨🇳

    We explain the achievements that were awarded 2022 Nobel Prize in Physics, as well as the preceding and the later developments. The main notions and historic cornerstones of Bell inequalities, the related researches on quantum entanglement are reviewed, and the key physical ideas are emphasized. Among the early work, C. S. Wu's contributions using polarization-entangled photons from electron-positron annihilation are introduced.

    ↳ physics.hist-phhep-phquant-ph1 citation
38. 38*

    Resurgent structure of the 't Hooft-Polyakov monopole

    Michal Malinský🇨🇿

    In this letter we present a comprehensive analysis of the differential equations governing the spatial profile of the 't~Hooft-Polyakov monopole from the viewpoint of resurgence theory. We note that the universality of the gauge-component asymptotics, together with the relative simplicity of its Borel transform and the associated Volterra equations' kernels, gives rise to a perturbative expansion featuring a good control over the proliferation of the Borel-plane singularities to all orders, along with full information about the relevant logarithmic discontinuities. Moreover, its partial resummation reveals remarkably simple universal analytic non-perturbative background profiles, around which one can develop a uniformly convergent global perturbative expansion of the exact solutions for any $\lambda /e^2>0$. This also provides an analytic grip on the numerical parameters governing the expansions of both the gauge and scalar profile functions at the origin and at infinity.

    ↳ hep-thhep-phPRD(2026)·2 citations
39. 39*

    Bounds on Lorentz invariance violation from muon fluctuations at the Pierre Auger Observatory

    The Pierre Auger Collaboration · A. Abdul Halim · P. Abreu · M. Aglietta · I. Allekotte · K. Almeida Cheminant · R. Aloisio · J. Alvarez-Muñiz · A. Ambrosone · J. Ammerman Yebra · L. Anchordoqui · B. Andrada and 348 other authors

    Quantum gravity theories often modify spacetime symmetries. In particular, Lorentz invariance may be violated when approaching the Planck scale. Although the scales at which interactions occur in extensive air showers induced by ultra-high-energy cosmic rays in the atmosphere are many orders of magnitude below the Planck scale, these violations might still be observable. In this work, the fluctuations in the number of muons in the extensive air showers measured at the Pierre Auger Observatory are exploited, for the first time, to constrain Lorentz invariance violations. The bounds derived in the hadronic sector are the strongest ever obtained, and do not rely on assumptions about the mass composition of ultra-high-energy cosmic rays. The fluctuations in the number of muons constitute a new and powerful observable to further explore Lorentz invariance in a region of the parameter space not accessible to other observables.

    ↳ astro-ph.HEgr-qchep-phPRL(2026)·2 citations
40. 40*

    Diffeomorphism Invariant Formulation of CP Violation

    Alibordi Muhammad🇵🇱

    We identify a fundamental tension between the standard formulation of CP violation and diffeomorphism invariance in general relativity. The effective Hamiltonian approach, while phenomenologically successful, relies on a preferred time foliation that is incompatible with general covariance. The CP-violating phases are scalars along the worldline of the decaying parent particle; however, the definition of masses and phases presupposes a local covariant structure, which becomes ill-defined near the origin where curvature is large and metric fluctuations become significant. We propose an information-geometric framework based on relative entropy, exploiting pure quantum states in particle and antiparticle Hilbert spaces. We show how the Sakharov conditions could be reinterpreted in terms of information-geometric quantities, although a fully rigorous phenomenological implementation remains to be developed.

    ↳ gr-qchep-ph0 citations
41. 41*

    RG-Invariant Symmetry Ratio for QCD: A Study of $U(1{)}_A$ and Chiral Symmetry Restoration

    Ting-Wai Chiu🇹🇼 · Tung-Han Hsieh🇹🇼

    We introduce a renormalization-group-invariant (RGI), scheme-independent symmetry ratio ${\kappa }_{AB}$, for the quantitative characterization of symmetry breaking in QCD. As a first application, we employ ${\kappa }_{AB}$ to investigate the relative strength of $SU(2{)}_L\times SU(2{)}_R$ chiral symmetry and $U(1{)}_A$ axial symmetry breaking in $N_f=2+1+1$ lattice QCD using optimal domain-wall fermions at the physical point. Our study covers three lattice spacings and twelve temperatures in the range 164--385~MeV. We examine three independent symmetry-breaking channels in the nonsinglet sector with quark-connected correlators: the $U(1{)}_A$-sensitive scalar--pseudoscalar channel (${\kappa }_{PS}$), probing the $\pi$--$\delta$ system; the $SU(2{)}_L\times SU(2{)}_R$-sensitive vector--axial-vector channel (${\kappa }_{VA}$), probing the $\rho$--$a_1$ system; and an additional $U(1{)}_A$-sensitive tensor vector--axial-tensor vector channel (${\kappa }_{TX}$), probing the ${\rho }_T$--$b_1$ system. At finite lattice spacing, we observe a clear hierarchy ${\kappa }_{PS}>{\kappa }_{VA}>{\kappa }_{TX}$. A controlled continuum extrapolation reveals that this hierarchy collapses, with all three symmetry-breaking strengths becoming statistically indistinguishable within our precision. This result provides a new, model-independent benchmark from a chirally symmetric lattice action. Our findings indicate that in the continuum limit the $SU(2{)}_L\times SU(2{)}_R$ and $U(1{)}_A$ channels in the nonsinglet sector reach degeneracy at the same temperature, already at the lowest simulated point of $164$~MeV, so that the two symmetries restore concurrently near the chiral crossover rather than at parametrically separated scales.

    ↳ hep-lathep-ph4 citations
42. 42*

    Gravitational Wave Echoes of the First Order Phase Transition in a Kination-Induced Big Bang

    Richard Casey🇺🇸 · Katherine Freese🇺🇸 · Evangelos I. Sfakianakis🇺🇸

    Gravitational waves (GWs) produced during first-order phase transitions (FOPTs) in the early universe provide a powerful probe of nonstandard cosmological histories. We study GW production from a FOPT ending a kination-dominated epoch in the Kination-Induced Big Bang scenario, in which a period of kination domination terminates through a phase transition that reheats the universe into radiation domination. A rolling scalar field drives the kination epoch. In the specific model we consider, its derivative coupling to a second scalar (tunneling field) dynamically traps the latter in a false vacuum, with the phase transition triggered as the kination field slows due to Hubble friction. We compute the resulting stochastic GW background from bubble nucleation and collisions, presenting analytic estimates and numerical results for the peak amplitude and frequency. In all cases we find an upper bound ${\Omega }_{\mathrm{GW}}{h}^2\lesssim 2\times 10^{-7}$ from the bubble percolation condition. In the case where the false vacuum energy dominates at the transition (yet the kination field drives the FOPT), we find ${\Omega }_{\mathrm{GW}}{h}^2\gtrsim 10^{-12}$. We further find that the Hubble scale during the phase transition across a broad set of model parameters is bounded by $\mathcal{O}(10^{-13})M^2/M_{\mathrm{Pl}}\lesssim H_{\ast }\lesssim \mathcal{O}(0.1)M^2/M_{\mathrm{Pl}}$, where $M$ is the mass-scale controlling the strength of the interaction between the kination and tunneling fields. The predicted signal spans frequencies from nHz to MHz, allowing the model to explain the signal reported by Pulsar Timing Array experiments and to be constrained or probed by interferometers such as LISA, Advanced LIGO, Cosmic Explorer, and BBO. Interestingly, a FOPT can occur even if the bare tunneling potential has a single minimum, as metastability is generated dynamically by the coupling between the tunneling and the kination field.

    ↳ astro-ph.COhep-phhep-th0 citations
43. 43*

    Prospects of Indirect Detection of Dark Matter via Primordial Black Hole Induced Gravitational Waves

    Debarun Paul🇮🇳 · Md Riajul Haque🇮🇳 · Supratik Pal🇮🇳

    Primordial black holes (PBHs), produced in the early Universe, can source a stochastic background of induced gravitational waves (GWs) and provide a non-thermal origin for dark matter (DM). We investigate DM production in a PBH-dominated cosmological framework, including contributions from PBH evaporation, gravitational production, and thermal freeze-in and freeze-out mechanisms, and determine the regions consistent with the observed DM relic abundance. We find that thermal freeze-in can compensate for the underabundance of PBH-sourced DM, while indirect detection remains largely insensitive due to the feeble interaction strength, making future GW observatories such as LISA and the Einstein Telescope (ET) unique probes of this scenario. For freeze-out DM, indirect detection experiments constrain regions with relatively large annihilation cross-sections, whereas GW observations probe complementary regions with heavier DM masses and smaller interaction strengths. Consequently, the same DM parameter space cannot be simultaneously probed by both indirect detection searches and GW missions. These results establish GW observations as a powerful and independent probe of DM production in PBH-dominated cosmologies, opening a new observational window into DM properties and the thermal history of the pre-BBN Universe.

    ↳ astro-ph.COhep-phJCAP(2026)·1 citation
44. 44*

    Imprints of asymptotic freedom on confining strings

    Jan Albert🇺🇸 · Alexandre Homrich🇺🇸

    We consider the Polyakov loop correlator in the confining phase of large $N$ Yang-Mills theory in three and four dimensions. It can be computed by summing over the exchange of closed flux tubes winding around the thermal cycle. At short separations, the leading divergence is controlled by perturbation theory. Combining these two facts allows us to determine the asymptotic spectral density of string states contributing to the correlator. This sharply relates the weakly-coupled UV of the gauge theory to the dynamics of highly energetic flux tubes. Then, in a toy integrable setting, we explore how this can bound the scattering data of the Goldstone modes on top of a long string. We derive a bound on the asymptotic behavior of the reflection amplitude of Goldstones against the flux tube boundary sourced by the Polyakov line, and rule out an asymptotically linear phase shift for the S-matrix. Along the way, we discuss how causality can impose bounds on thermodynamic quantities, and show how the positivity of time delays follows from unitarity and analyticity of $2d$ massless elastic S-matrices. We include a review on reflection amplitudes, and their computation in the theory of long effective strings.

    ↳ hep-thhep-lathep-phPRL(2026)·8 citations
45. 45*

    ABCMB: A Python+JAX Package for the Cosmic Microwave Background Power Spectrum

    Zilu Zhou🇺🇸 · Cara Giovanetti🇺🇸 · Hongwan Liu🇺🇸

    We present ABCMB, a differentiable Einstein-Boltzmann solver for the cosmic microwave background (CMB). ABCMB is a complete code capturing important effects to linear order in $\Lambda \mathrm{CDM}$ cosmology. It computes the CMB power spectrum and includes effects like lensing, polarization, massive neutrinos, and a state-of-the-art treatment of BBN and recombination. ABCMB has sub-percent-level agreement with CLASS and can be run on a GPU with competitive, and sometimes even faster, run times. It is refactored compared to previous codes and takes advantage of object-oriented programming to improve extensibility, meaning new physics can be added to it without the need for modifying source files. ABCMB provides accurate and stable gradients to the user, making Fisher analyses straightforward, and enabling the use of efficient gradient-based sampling methods.

    ↳ astro-ph.COhep-phJCAP(2026)·4 citations
46. 46*

    Measuring Pulsar Distances from Chirping Orbital Periods

    Brady Egleston · Reza Ebadi🇺🇸 · Ronald Walsworth🇺🇸

    The observed orbital period time derivative (or orbital "chirp") of a millisecond binary pulsar (MSP) encodes information about both the intrinsic properties of the binary system and its environment. Orbital chirp has contributions from intrinsic energy loss due to gravitational wave emission, kinematic effects due to motion in the plane of the sky, and dynamical effects due to galactic acceleration, with the latter two contributions depending on the MSP distance. We use orbital chirp data to infer distances to 21 MSPs; and for four of which we obtain smaller uncertainties than those reported in previous distance measurements. We incorporate multiple realistic galactic acceleration models to assess the sensitivity of the inferred distances to the choice of galactic gravitational potential, finding a significant dependence for four MSPs.

    ↳ astro-ph.HEastro-ph.COastro-ph.GAgr-qc+11 citation
47. 47*

    Orbital eccentricity can make neutron star g-mode resonances observable with current gravitational-wave detectors

    János Takátsy🇭🇺 · Lorenz Zwick🇩🇰 · Pankaj Saini🇩🇰 · Johan Samsing🇩🇰

    Dynamical tides can provide us vital information about the properties of neutron star (NS) matter. This is particularly true for g-modes, whose frequency and tidal coupling are highly sensitive to the composition of NSs, especially in their centers, where microphysical models are the least reliable. However, due to their weak coupling to external tidal fields, their effect on the gravitational-wave (GW) signal of binary inspirals can be difficult to observe. Here we show that the detectability of these tides can be significantly enhanced by binary NSs with moderate eccentricities. This is primarily due to higher eccentric harmonics in the early phase of the binary evolution experiencing larger phase shifts, which they transport to the sensitive band of GW detectors. In addition, g-mode tides in eccentric binaries undergo several epicyclic resonances, which also amplify the total phase shift. We demonstrate that these effects increase the detectability of g-mode dynamical tides by more than an order of magnitude for eccentricities of $e_{10Hz}\sim 0.2-0.4$, making it possible to put robust constraints on g-mode properties using current GW detectors, while all relevant models could potentially be constrained with eccentric binary NSs with Einstein Telescope.

    ↳ astro-ph.HEhep-phnucl-thPRD(2026)·3 citations
48. 48*

    Experimental characterization of the hierarchy of quantum correlations in top quark pairs

    Yoav Afik🇺🇸 · Regina Demina🇺🇸 · Alan Herrera🇺🇸 · Otto Hindrichs🇺🇸 · Juan Ramón Muñoz de Nova🇪🇸 · Baptiste Ravina🇨🇭

    Recent results from the Large Hadron Collider have demonstrated quantum entanglement of top quark-antiquark pairs using the spin degrees of freedom. Based on the doubly differential measurement of the spin density matrix of the top quark and antiquark performed by the CMS collaboration in the helicity and beam bases, we evaluate a set of quantum observables, including discord, steerability, Bell correlation, and magic. These observables allow for a quantitative characterization of the quantum correlations present in a top quark-antiquark system, thus enabling an interpretation of collider data in terms of quantum states and their properties. Discord is observed to be greater than zero with a significance of more than 5 standard deviations ($\sigma$) in several regions of phase space, some of which correspond to separable quantum states. Evidence for steerability is established for the first time in a high-energy system, with a significance of more than 3$\sigma$. No Bell correlation is observed within the currently probed phase space, in agreement with the theoretical prediction. These results experimentally corroborate the hierarchy of quantum correlations in top quarks with discord being the most basic form of quantum correlation, followed by entanglement, steerability, and Bell correlation. The significance of nonzero magic, which is a complementary observable to the quantum correlation hierarchy, is found to exceed 5$\sigma$ in several regions of phase space.

    ↳ quant-phhep-exhep-phPRD(2026)·12 citations
49. 49*

    Detection horizon for the neutrino burst from the stellar helium flash

    Pablo Martínez-Miravé🇩🇰 · Irene Tamborra🇩🇰 · Georg Raffelt🇩🇪

    Low-mass stars ($M\lesssim 2M_{\odot }$) ignite helium under degenerate conditions, eventually causing a nuclear run-away -- the helium flash. The alpha-capture process on ${}^{14}$N produces a large amount of ${}^{18}$F, whose subsequent decay spawns an intense ${\nu }_e$ burst (with average energy of $0.38$ MeV) lasting about a day. We show that, in addition, a strong $1.7$ MeV neutrino line is generated by electron capture on ${}^{18}$F. Detection is hindered by large backgrounds in state-of-the-art neutrino observatories, such as JUNO. In next-generation facilities, such as the Jinping neutrino experiment, the horizon for a detection with a local significance of $3\sigma$ would be extended to almost $3$ pc. Although helium flashes occur a few times per year in our Galaxy, there are no stellar candidates approaching the tip of the red giant branch within $10$ pc. Hence, to date, asteroseismology remains the most promising tool for probing the most energetic thermonuclear event in the life of a low-mass star.

    ↳ astro-ph.SRastro-ph.HEhep-exhep-phPRD(2026)·0 citations
50. 50*

    Mathematical Paradoxes of Dirac Equation Representations

    V.P.Neznamov🇷🇺

    This paper examines the Foldy-Wouthuysen and Feynman-Gell-Mann representations of the Dirac equation. The analysis is conducted for electrons and positrons interacting with electromagnetic fields. Versions of quantum electrodynamics are considered both within the scope of perturbation theory and in the nonperturbative case with strong electromagnetic fields. Mathematical artifacts that contradicting the physical premises of the theory are identified in the studied representations of the Dirac equation. These mathematical paradoxes are resolved if the theory only employs amplitude states (real and virtual) with positive energies.

    ↳ hep-thhep-phquant-phPhys.Usp.(2025)·0 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.