Effect of medium dependent binding energies on inferring the temperatures and freeze-out density of disassembling hot nuclear matter from cluster yields

TL;DR

This paper investigates how medium-dependent binding energy modifications affect the inference of temperature and density in disassembling hot nuclear matter using cluster yields, highlighting the importance of medium effects at higher densities.

Contribution

It extends the ACCR method by incorporating medium modifications of cluster properties, improving the accuracy of temperature and density estimations from nuclear fragment yields.

Findings

Medium effects significantly alter nucleon density estimates at higher densities.

Temperature estimates are modestly affected by medium modifications at low densities.

Inclusion of medium effects improves the interpretation of cluster yield data.

Abstract

We explore the abundance of light clusters in asymmetric nuclear matter at subsaturation density. With increasing density, binding energies and wave functions are modified due to medium effects. The method of Albergo, Costa, Costanzo and Rubbino (ACCR) for determining the temperature and free nucleon density of a disassembling hot nuclear source from fragment yields is modified to include, in addition to Coulomb effects and flow, also effects of medium modifications of cluster properties, which become of importance when the nuclear matter density is above 10$^{-3}$ fm$^{-3}$. We show how the analysis of cluster yields, to infer temperature and nucleon densities, is modified if the shifts in binding energies of in medium clusters are included. While, at low densities, the temperature calculated from given yields changes only modestly if medium effects are taken into account, larger discrepancies are observed when the nucleon densities are determined from measured yields.