Probing densities of hot nuclei

Study of density dependence of symmetry energy requires quantitative information about the excitation energy dependence of nuclear density. In the present work, kinetic energy spectra of fragments arising from the reactions $^{78,86}$Kr+$^{58,64}$Ni, ($E_{lab}$= 35 MeV/A) have been analyzed to get information about the nuclear density. A reconstructed quasi-projectile was chosen as the fragmenting source with appropriate conditions. In order to investigate the excitation energy dependence of the nuclear density, kinetic energy spectra of fragments, gated on different excitation energy of the fragmenting source, were analyzed within the framework of a binary break up. In order to account for the variation in Coulomb repulsion seen by a fragment in different break up events, an average Coulomb repulsion was calculated by varying the charge of the residual nucleus. In the analysis, the radius constant was one of the free parameters. The density profile obtained from the values of radius constant at various excitation energies was found to be in a reasonable agreement with that reported in literature based on similar analysis.