New approach of fragment charge correlations in 129Xe+(nat)Sn central collisions

Abstract

A previous analysis of the charge (Z) correlations in the $ΔZ-<Z>$ plane for Xe+Sn central collisions at 32 MeV/u has shown an enhancement in the production of equally sized fragments (low $ΔZ$) which was interpreted as an evidence for spinodal decomposition. However the signal is weak and rises the question of the estimation of the uncorrelated yield. After a critical analysis of its robustness, we propose in this paper a new technique to build the uncorrelated yield in the charge correlation function. The application of this method to Xe+Sn central collision data at 32, 39, 45 and 50 MeV/u does not show any particular enhancement of the correlation function in any $ΔZ$ bin.

23 pages, 9 figures, revised version with an added figure and minor changes. To appear in Nuclear Physics A