Nuclear Experiment·nucl-ex

Fri·Aug 14, 2026Friday·August 14, 2026

3 papers—0 primary·3 cross-listed

01
How Neutron Star Radii Encode the Dense-Matter Equation of State and Hadron-Quark Transition
Bao-An Li🇺🇸 · Xavier Grundler🇺🇸
We investigate how future high-precision neutron star (NS) radius measurements encode microscopic information about the dense-matter equation of state (EOS), focusing on a possible first-order hadron--quark phase transition and the resulting mass--radius topology. Within a Bayesian framework using meta-model EOSs with nine microscopic parameters, we analyze mock radius measurements $R_{1.4} = 11.9 \pm σ_{R}$ km with $σ_{R} = 0.9$ and $0.1$ km for canonical NSs. We introduce inverse EOS--radius mappings that give the posterior mean of each EOS parameter as a function of $R_{1.4}$ . Their slope measures radius sensitivity, while their curvature determines the leading precision dependence of the posterior mean through the Jensen expansion. Resolving the mappings into four mass--radius topologies, Connected, Disconnected, Both, and No-Quark-Matter, reveals a clear hierarchy of information. The symmetry-energy parameters $L$ (slope) and $K_{sym}$ (curvature) are strongly encoded in $R_{1.4}$ and their posterior means shift appreciably with improved radius precision, whereas the higher-order hadronic parameters show stronger topology dependence. Among the transition parameters, the transition density $ρ_{t}$ is the most strongly encoded in $R_{1.4}$ , while the energy-density jump and quark-matter sound speed are more strongly associated with the topology of the full mass--radius sequence. Since the different topologies have strongly overlapping $R_{1.4}$ distributions, even precise radius measurements cannot by themselves identify the topology or uniquely determine the high-density transition properties. These results provide a parameter-dependent hierarchy for assessing the scientific return of future high-precision radius measurements and complementary probes of high-density
↳ astro-ph.HEhep-phnucl-exnucl-th1 citation
02
Relativistic dynamical effects in proton emission: the Wentzel-Kramers-Brillouin method for 1+1 dimensional Dirac equation
Guangping Chen🇨🇳 · Wenmin Deng · Ganlong Ding · Sibo Wang🇨🇳 · Jing Peng · Haozhao Liang🇯🇵
Starting from the $1 + 1$ dimensional (one spatial and one temporal dimension) Dirac equation, we employ the Wentzel-Kramers-Brillouin (WKB) approximation to derive the corresponding relativistic penetration probability. The derivation shows that the semiclassical momentum is determined by the Schrödinger-equivalent potential $U_{eff} (r) = S (r) + \frac{E}{m} V (r) + \frac{S ^{2} ( r ) - V ^{2} ( r )}{2 m}$ , instead of the simple sum of scalar and vector potentials $S (r) + V (r)$ , which has been adopted widely in the studies of relativistic quantum tunneling. We then quantify the relativistic dynamical effects in proton emission by comparing the results obtained with $U_{eff} (r)$ and those obtained with $S (r) + V (r)$ . Incorporating $U_{eff} (r)$ systematically reduces the penetration probability and the assault frequency, and consequently increases the predicted half-life. The relativistic dynamical effect becomes more pronounced with higher orbital angular momentum and can reach about $84%$ in the half-life of $^{144} Tm$ .
↳ nucl-thnucl-ex0 citations
03
Non-perturbative quark production and transport in the evolving glasma: the WAGASHI event generator
Nicholas J. Benoit🇯🇵 · Chiho Nonaka🇯🇵 · Hidetoshi Taya🇯🇵
We study non-perturbative quark-antiquark pair production and the subsequent quark dynamics in the earliest glasma stage of relativistic heavy-ion collisions. For that, we develop a new model, WAGASHI (Wong-precessing Anisotropic Glasma And ScHwinger-produced Initial-conditions), which combines classical Yang-Mills glasma evolution, Wong-equation transport, and Schwinger pair production on an event-by-event basis. We find that a sizeable number of quarks, comparable to the final hadron yields, are produced already during the glasma stage and subsequently undergo substantial momentum broadening and spin randomization, suggesting a significant contribution toward the early equilibration of the quark-gluon plasma. We also determine the event-by-event distributions of baryon number, electric charge, strangeness, and spin polarization in Pb-Pb and O-O collisions at LHC energies, finding particularly large fluctuations in the smaller O-O system. These results provide dynamical initial conditions for the subsequent hydrodynamic evolution of the quark-gluon plasma.
↳ hep-phhep-exnucl-exnucl-th0 citations

Affiliations

first authorsco-authorsvia INSPIRE

How Neutron Star Radii Encode the Dense-Matter Equation of State and Hadron-Quark Transition

Relativistic dynamical effects in proton emission: the Wentzel-Kramers-Brillouin method for 1+1 dimensional Dirac equation

Non-perturbative quark production and transport in the evolving glasma: the WAGASHI event generator

Affiliations