Abstract Nuclear transparency in the electronuclear reaction $A(e,e'K^+)$ is investigated
in parallel with our previous study of pion transparency in
Phys.\ Rev.\ C {\bf 111}, 064608 (2025). Based on an extended Glauber
framework that incorporates shadowing from the initial-state two-step
process, kaon color transparency (CT) is analyzed to show that the
steeper $Q^2$ dependence observed for kaon CT, compared with the pion
case, is more naturally described by the naive parton model (NPM) than
by the quantum diffusion model (QDM). The inclusion of initial-state
shadowing further reduces the transparency and improves the agreement
with the experimental data. The $Q^2$ and $A$ dependences of the kaon
transparency are presented up to $Q^2=10$~GeV$^2/c^2$, together with the
corresponding $\alpha(Q^2)$ and the supplementary ratio $T_A/T_C$, for
comparison with the Jefferson Lab (JLab) data obtained with the 6-GeV
electron beam on $^{12}$C, $^{63}$Cu, and $^{197}$Au nuclei.

Abstract We report enhanced evidence for the $X(7200)$ state and significantly improved measurements of the $X(6900)$ resonance parameters through a combined analysis of the di-$J/\psi$ mass spectrum using published data from LHCb, ATLAS, and CMS. By performing simultaneous fits to all three experiments, we observe the $X(6900)$ with overwhelming significance ($>12\sigma$) and determine its mass and width with improved precision. For the $X(7200)$, we find consistent signals across multiple interference models, with significances ranging from $3.7\sigma$ to $6.6\sigma$; the best-fit model (adopting the CMS three-resonance scheme) yields $6.6\sigma$ significance, providing substantially strengthened evidence for this state. Our results underscore the essential role of interference effects in fully-charmed tetraquark spectroscopy and offer new constraints on their production mechanisms at the LHC.

Abstract Angular momentum projection is a basic technique in constructing nuclear wave functions with good spins. Traditionally, a projected nuclear wave function is expressed in terms of the bases built by performing the angular momentum projection directly on reference states for the whole nuclear system. Alternatively, one can construct nuclear wave function with another kind of projected bases, called as the coupled projected bases, which are generated by first performing the angular momentum projections on the reference states for neutrons and protons, respectively, then coupling the neutron projected states with the proton ones via Clebsch–Gordon coefficients. In the present work, we derive a new identity, which provides a decomposition of the conventional angular momentum projected nuclear wave function in terms of the coupled projected bases. This decomposition offers direct insight into the underlying structure of nuclear states. To show this point, we present the decompositions of variation after projection shell model (VAPSM) wave functions for the ground states in some $sd$ shell nuclei. It is interesting to see that even for the ground states in even-even nuclei, the nucleons are not fully paired. Finally, we demonstrate that the VAPSM wave function can be further improved by adopting the coupled projected bases.

The Galactic Center GeV Excess (GCE) remains a compelling but enigmatic signal from the inner regions of our galaxy. Muonphilic dark matter (DM), which couples exclusively to muons via a new mediator, provides a viable explanation for the GCE and relic density while naturally evading constraints from direct detection, collider searches, and other multimessenger observations. Based on the viable nonresonant parameter space identified in previous global fits, we perform a comprehensive study on the prospects for discovering such muonphilic DM in the context of a future 3 TeV muon collider, focusing on simplified models with a -even mediator. Four distinct search strategies are investigated: visible on-shell mediator decays ( final state), invisible on-shell mediator decays (mono-photon plus missing energy), mono-photon production via off-shell mediators, and vector boson fusion production. Through a detailed signal-background analysis using cut-and-count methods, we project the exclusion limits at % confidence level for seven representative models across a wide range of mediator masses. Our results demonstrate that the projected limits cover a significant portion of viable parameter space that explains the GCE, establishing a muon collider as a decisive machine for testing the muonphilic DM hypothesis.

The simulation of the observed properties of type I X-ray bursts, also known as superbursts, poses challenges once Cooper pair neutrino emission from the crust of the neutron star are included. Further, additional heating of the accumulating fuel layer is required. The emission of γ-rays caused by electron captures to excited states in astrophysical environments is a major source of heat loss competing with that carried away by weak-interaction neutrinos. γ-heating significantly affect the presupernova evolution of massive stars and the calculation of the thermal structure in the crust and core of superbursts. This energy deposition enhances entropy production and promotes convection at this stage of stellar evolution. Effective γ-heating rates reduce the ignition depth of superbursts. A recent investigation ranked the leading electron capturing nuclei as the cause for significant changes in the lepton-to-baryon fraction ( ) of the stellar matter after silicon core burning. We investigate γ-heating rates from the excited states of the top 100 electron capture and positron decay nuclei identified in recently published ranking lists. Each nucleus was analyzed using four different empirical pairing gaps and three distinct sets of nuclear deformation parameters to assess the effect of γ-heating rates. We report our calculations for the temperature range of 1−10 GK and density range of − g/cm . The calculated γ-heating rates changes up to a factor 26 (16) with changing deformation values (pairing gaps). Our findings may contribute to more realistic simulations of post-silicon burning phases of massive stars and superbursting neutron stars.

The quark-mass dependence of the pole is analyzed using the K-matrix method, with the scattering amplitude calculated up to the order in the chiral perturbation theory. As the quark mass increases, the pole gradually approaches the real axis in the complex w-plane (where ). Eventually, in the case, it crosses the u-cut on the real axis and enters the adjacent Riemann sheet when the pion mass reaches . At order , the rate at which it approaches the real axis decreases; however, it remains uncertain whether it will ultimately cross the u-cut and enter the adjacent Riemann sheet. In addition, the trajectory of the pole is in qualitative agreement with the results from the linear σ model calculation.

Abstract We extract the non-perturbative Heavy Quark Effective Theory (HQET) parameters from the inclusive semi-leptonic decay Λ c + →Xe + ν e . Unlike charmed mesons produced near threshold, Λ c + baryons produced in e + e - annihilation exhibit a complex momentum distribution, making the transformation of the electron energy spectrum from the laboratory frame to the Λ c + frame non-trivial. To address this, we develop a novel Bayesian inference method to reconstruct the electron energy moments in the Λ c + rest frame. By performing a global fit of theoretical predictions in the 1S mass scheme to these extracted moments, we determine the HQET parameters μ π 2 (Λ c + ) and ρ D 3 (Λ c + ) the first time using a purely data-driven approach. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.

Abstract In this paper, we investigate the quantum gravitational corrections to the thermodynamical quantities of Reissner-Nordström black holes within the framework of effective field theory. The effective action originates from integrating out massless particles, including gravitons, at the one-loop level. We perform a complete thermodynamic analysis for both non-extremal and extremal black holes, and are mainly concerned about the shift in the charge-to-mass ratio $q/M$ that plays an important role in analyzing the weak gravity conjuecture. For non-extremal black holes, we identify a relationship between the shift in the charge-to-mass ratio and the thermodynamic stability of the black holes. For extremal black holes, we show that quantum gravity effects naturally lead to the super-extremality $q/M>1$ of charged black holes.

We propose a cosmological framework in which neutrino masses evolve dynamically through coupling with a scalar field that simultaneously drives inflation. The neutrino mass is modeled as a power-law, exponential, or hybrid function of the scalar field, yielding an effective potential that includes neutrino backreaction. Starting from the Einstein–Hilbert action in a flat FLRW background, we derive the modified Friedmann and Klein–Gordon equations incorporating this coupling. Using the Fermi–Dirac integrals, we account for the continuous transition of neutrinos from relativistic to nonrelativistic regimes. The inflationary dynamics are investigated through the slow-roll parameters derived from the effective potential, together with the evaluation of the scalar spectral index , and the tensor-to-scalar ratio r for each model. The exponential and mixed MaVaN couplings emerge as the most flexible cases, allowing inflationary dynamics and neutrino mass variation to be accommodated within a single scalar field, only in a constrained region of the parameter space.

Abstract We investigate the steady, axisymmetric, force-free magnetosphere of Kerr–Sen black hole (BH) within the framework of the Einstein–Maxwell–dilaton–axion (EMDA) theory. By perturbatively solving the nonlinear Grad–Shafranov (GS) equation, we determine the magnetic field configuration and quantify the influence of the dilaton parameter $r_2$ on the energy extraction rate and radiative efficiency. Our results show that both the energy extraction power and the radiative efficiency increase with $r_2$, exceeding those of the standard Kerr BH, whereas the extraction efficiency remain consistent with the Kerr case. In addition, we perform $\chi^2$ statistical analysis using observational data from six binary BH systems, which indicates that the Kerr BH currently provides a better fit for bulk Lorentz factors $\Gamma = 2$ and $5$