A systematic study of the nuclear caloric curve

Temperature-excitation energy correlation measurements on several systems a t different incident energies are discussed in the framework of the investi gation on possible liquid-gas phase transition in nuclear matter. Results a re compared to the presently available experimental caloric curves. Moreove r the isotope and the excited states temperatures, extracted from double ra tios of isotope yields and population ratios of fragment unbound states, re spectively, are compared. The differences on the temperatures deduced from the two methods cannot be accounted for by the sequential feeding corrections. Instead, they seem to be related to the space-time evolution of the fragmentation process.