Fri·Dec 13, 2024Friday·December 13, 2024

1. 01*

   Photo-Induced Quenching of the 229Th Isomer in a Solid-State Host

   J. E. S. Terhune🇺🇸 · R. Elwell🇺🇸 · H. B. Tran Tan🇺🇸 · U. C. Perera🇺🇸 · H. W. T. Morgan🇺🇸 · A. N. Alexandrova🇺🇸 · Andrei Derevianko🇺🇸 · Eric R. Hudson🇺🇸

   The population dynamics of the 229Th isomeric state is studied in a solid-state host under laser illumination. A photoquenching process is observed, where off-resonant vacuum-ultraviolet (VUV) radiation leads to relaxation of the isomeric state. The cross-section for this photoquenching process is measured and a model for the decay process, where photoexcitation of electronic states within the material bandgap opens an internal conversion decay channel, is presented and appears to reproduce the measured cross-section.

   ↳ physics.atom-phnucl-exPRResearch(2025)·19 citations
2. 02*

   Extended Skyrme effective interactions with higher-order momentum-dependence for transport models and neutron stars

   Si-Pei Wang🇨🇳 · Xin Li🇨🇳 · Rui Wang🇮🇹 · Jun-Ting Ye🇨🇳 · Lie-Wen Chen🇨🇳

   The recently developed extended Skyrme effective interaction based on the so-called N3LO Skyrme pseudopotential is generalized to the general N$n$LO case by incorporating the derivative terms up to 2$n$th-order into the central term of the pseudopotential. The corresponding expressions of Hamiltonian density and single-nucleon potential are derived within the Hartree-Fock approximation under general nonequilibrium conditions. The inclusion of the higher-order derivative terms provides additional higher-order momentum dependence for the single-nucleon potential, and in particular, we find that the N5LO single-nucleon potential with momentum dependent terms up to $p^{10}$ can give a nice description for the empirical nucleon optical potential up to energy of $2$ GeV. At the same time, the density-dependent terms in the extended Skyrme effective interaction are extended correspondingly in the spirit of the Fermi momentum expansion, which allows highly flexible variation of density behavior for both the symmetric nuclear matter equation of state and the symmetry energy. Based on the Skyrme pseudopotential up to N3LO, N4LO and N5LO, we construct a series of interactions with the nucleon optical potential having different high-momentum behaviors and with the symmetry potentials featuring different linear isospin-splitting coefficients for nucleon effective mass, by which we study the properties of nuclear matter and neutron stars. Furthermore, within the lattice BUU transport model, some benchmark simulations with selected interactions are performed for the Au+Au collisions at a beam energy of $1.23$ GeV/nucleon, and the predicted collective flows for protons are found to nicely agree with the data measured by HADES collaboration.

   ↳ nucl-thastro-ph.HEhep-phnucl-exPRC(2025)·13 citations
3. 03*

   Effective temperatures of the QGP from thermal photon and dilepton production

   Olaf Massen🇳🇱 · Govert Nijs🇨🇭 · Mike Sas🇳🇱 · Wilke van der Schee🇨🇭 · Raimond Snellings🇳🇱

   Thermal electromagnetic radiation is emitted by the quark-gluon plasma (QGP) throughout its space-time evolution, with production rates that depend characteristically on the temperature. We study this temperature using thermal photons and dileptons using the Trajectum heavy ion code, which is constrained by Bayesian analysis. In addition we present the elliptic flow of both the thermal photons and thermal dileptons including systematic uncertainties corresponding to the model parameter uncertainty. We give a comprehensive overview of the resulting effective temperatures $T_{\mathrm{eff}}$, obtained from thermal photon transverse momentum and thermal dilepton invariant mass distributions, as well as the dependence of $T_{\mathrm{eff}}$ on various selection criteria of these probes. We conclude that the $T_{\mathrm{eff}}$ obtained from thermal photons is mostly insensitive to the temperature of the QGP with a value of $T_{\mathrm{eff}}\sim$ 250-300 MeV depending on their transverse momentum, almost independent of collision centrality. Thermal dileptons are much better probes of the QGP temperature as they do not suffer from a blue shift as their invariant mass is used, allowing for a more precise constraint of the QGP temperature during different stages of the evolution of the system. By applying selection criteria on the dilepton transverse momentum and the invariant mass we are able to extract fluid temperatures on average times ranging from late emission ($⟨\tau ⟩=5.6$fm$/c$) to very early emissions ($⟨\tau ⟩<1.0$fm$/c$). Furthermore, we show how these selection criteria can be used to map the elliptic flow of the system all throughout its evolution.

   ↳ nucl-thhep-phnucl-exEPJC(2025)·17 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.