D. Henzlova a, M. V. Ricciardi a, J. Benlliure b, A. S. Botvina a, T. Enqvist a, A. Keli ć a, P. Napolitani a, J. Pereira b, K.-H. Schmidt a a GSI-Darmstadt, Germany b Univ. Santiago de Compostela, Spain Investigation of the N/Z of the heavy fragmentation products – the isospin thermometer method

information from IMFs and light fragments only  extension of the thermometry towards the heavy fragments measurements of temperature T freeze-out from these methods ~ 5MeV investigation of the properties of the nuclear matter under extreme conditions (E*, density, isospin…) understanding the supernovae explosions, formation and stability of neutron stars… onset of rapid disintegration of nucleus observed for high E* J. Pochodzalla et al., Phys. Rev. Lett. 75 (1995) 1040 liquid-gas phase transition in NM nuclear caloric curveMotivation

disturbing effect of evaporation Important issues 208 Pb+d 1AGeV the FRagment Separator (FRS) full isotopic identification evaporation residue corridor properties of nuclei after long evaporation largely universal

final fragments keep higher /Z than the EPAX prediction lack of excitation energy at the beginning of evaporation final fragments scale with the N/Z of the projectile long evaporation process keeps a memory on the initial N/Z of the system fission excluded! T.Enqvist, et al.; Nuc. Phys. A658 (1999) 47 T.Enqvist, et al.; Nuc. Phys. A703 (2002) 435 M.V.Ricciradi, et al.; proc. of XXXI Hirschegg Workshop, Jan Systematic investigation of /Z of heavy fragmentation products

E* deposited in the prefragment by far exceeds the E* corresponding to T~5MeV 238 U+Pb 1 AGeV ABRABLA calculation abrasion break-up evaporation abrasionevaporation excited prefragment possible scenario: Interpretation of the data two stage process:

the isospin thermometer method explores the reduction of N/Z in evaporation process to restore the E* after break-up abrasionbreak-up 238 U evaporation access to the fragment temperature at the freeze-out of the break-up stage upper limit of T freeze-out ~ 5.5 MeV Preliminary 136 Xe Understanding the observed features - the isospin thermometer method

FRS allows to extend the full isotopic identification up to the mass high E* introduced and observed deviation of the heavy fragmentation residues from the EPAX prediction signals a break-up process in their formation final fragments after evaporation still keep an important information about the reaction mechanism FRS data for neutron rich projectiles evaporation process = ‘tool’ to access the freeze-out of the break-up stage freeze-out temperature deduced from heavy residues in accord with IMFs investigationsSummary of the projectile