The nuclear liquidgas phase transition within Fermionic Molecular Dynamics.pdfVIP

The nuclear liquid–gas phase transition within Fermionic Molecular Dynamics J. Schnack 1 and H. Feldmeier 2 Gesellschaft f¨ur Schwerionenforschung mbH, 7 9 Postfach 110 552, D-64220 Darmstadt 9 Technische Hochschule Darmstadt 1 r a M Abstract 9 1 The time evolution of excited nuclei, which are in equilibrium with the surrounding vapour, is investigated. It is shown that the finite nuclear systems undergo a first 1 oder phase transition. The caloric curve is presented for excited 16O, 24Mg, 27Al v 40 16 2 and Ca and the critical temperature is estimated for O. 4 PACS: 24.10.Cn, 02.70.Ns, 05.30.-d, 05.30.Fk, 05.60.+w, 05.70.Fh 0 3 Keywords: Fermion system; Fermionic Molecular Dynamics; Time averaging; Er- 0 godic assumption; Nuclear liquid–gas phase transition; Critical temperature 7 9 / h t - l c u 1 Introduction n : v i X Mean–field models predict a first order phase transition for nuclear matter r with a critical temperature which depends on the proton–neutron asymmetry a [1–5]. A recent experimental attempt by the ALADIN group [6] to deduce an equation of state, which relates the excitation energy of a hot nucleus to its temperature, has stimulated both, theoretical and experimental efforts in this field [7–13]. In the experiment excited projectile spectators were investigated in Au+Au collisions at a beam energy of E/A = 600 MeV. While the equation of state refers to a stationary system where