Fri·Jul 4, 2025Friday·July 4, 2025

1. 01*

   Indirect Measurement of the ${}^{23}\text{Na}(p,\gamma {)}^{24}$Mg Direct Capture Reaction Rate via (${}^3$He,d) Spectroscopy

   Kaixin Song · Richard Longland🇺🇸 · Caleb Marshall🇺🇸 · Kiana Setoodehnia🇺🇸 · Federico Portillo Chaves · Axel Fraud

   The cross section of the ${}^{23}\text{Na}(p,\gamma {)}^{24}\text{Mg}$ reaction is dominated by direct capture at low energies relevant for stellar burning. Such cross sections can be constrained using spectroscopic factors($C^{2}S$) or asymptotic normalization coefficients(ANCs) from transfer reactions. In this work, the ${}^{23}\text{Na}{(}^3\text{He},d{)}^{24}\text{Mg}$ reaction was measured at $E_{lab}=21$ MeV to extract spectroscopic factors for ${}^{24}\text{Mg}$ states with excitation energies in $E_x=7\sim 12$MeV using the Enge split-pole spectrograph at the Triangle Universities Nuclear Laboratory. A new non-resonant astrophysical S factor and the direct capture reaction rate for the ${}^{23}\text{Na}(p,\gamma )$ reaction are calculated and presented based on this measurement. The new rate at $T<0.04$ GK is 43$\%$ smaller than in previous studies. Rigorous treatments of uncertainties are presented using a Bayesian Markov Chain Monte Carlo (MCMC) method. Sources of uncertainties for computing the direct capture cross section are also discussed in detail.

   nucl-exPRC(2025)·0 citations
2. 02*

   Extended momentum-dependent interaction for transport models and neutron stars

   Si-Pei Wang🇨🇳 · Lie-Wen Chen🇨🇳

   The momentum-dependent interaction (MDI) model, which has been widely used in microscopic transport models for heavy-ion collisions (HICs), is extended to include three different momentum-dependent terms and three zero-range density-dependent terms, dubbed as MDI3Y model. Compared to the MDI model, the single-nucleon potential in the MDI3Y model exhibits more flexible momentum-dependent behaviors. Furthermore, the inclusion of three zero-range density-dependent interactions follows the idea of Fermi momentum expansion, allowing more flexible variation for the largely uncertain high-density behaviors of nuclear matter equation of state (EOS), especially the symmetry energy. Moreover, we also obtain the corresponding Skyrme-like energy density functional through density matrix expansion of the finite-range exchange interactions. Based on the MDI3Y model, we construct four interactions with the same symmetry energy slope parameter $L=35$ MeV but different momentum dependence of $U_{\mathrm{sym}}$, by fitting the empirical nucleon optical potential, the empirical properties of symmetric nuclear matter, the microscopic calculations of pure neutron matter EOS and the astrophysical constraints on neutron stars. In addition, two interactions with $L=55$ and $75$ MeV are also constructed for comparison. Using these MDI3Y interactions, we study the properties of nuclear matter and neutron stars. These MDI3Y interactions, especially those with non-monotonic momentum dependence of $U_{\mathrm{sym}}$, will be potentially useful in transport model analyses of HICs data to extract nuclear matter EOS and the isospin splitting of nucleon effective masses.

   ↳ nucl-thastro-ph.HEhep-phnucl-exPRC(2025)·4 citations
3. 03*

   Constraining color-charge effects of partonic energy loss with jet axis-based inclusive jet substructure measurement

   Raghunath Pradhan🇺🇸 · Olga Evdokimov🇺🇸

   This study investigates the color-charge dependence of parton energy loss in the quark-gluon plasma (QGP) medium and the associated relative modifications of quark and gluon jet fractions compared to vacuum, using jet axis decorrelation observables. Recent CMS jet axis decorrelation measurements in PbPb collisions at 5.02 TeV are interpreted using Pythia simulations with varied quark/gluon jet compositions and emulated color-charge dependent energy loss. A template-fit procedure is employed to estimate the limits on gluon jet fractions in the published CMS data and average shift in jet momentum due to quenching for quark- and gluon-initiated jets traversing the QGP. The extracted gluon jet fractions and the estimated quark and gluon energy losses based on this study of jet axis decorrelations are found to be consistent with other model calculations based on inclusive observables. This work illustrates the use of jet substructure measurements for providing constraints on the color-charge dependence of parton energy loss and offers valuable insights for jet quenching models.

   ↳ hep-phhep-exnucl-exnucl-thPRC(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.