Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HK: Hadronen und Kerne

HK 52: Heavy Ion Reactions VI, Relativistic Energies

HK 52.4: Gruppenbericht

Mittwoch, 18. März 1998, 14:45–15:15, F

Nonlocal corrections to the Boltzmann equation for dense Fermi systems — •K. Morawetz¹, P. Lipavskyý², and V. Spička² — ¹FB Physik, Universität Rostock, Universitätsplatz 3, D-18051 Rostock — ²Institute of Physics, Academy of Sciences, Cukrovarnická 10, 16200 Praha 6, Czech Republic

A kinetic equation which combines the quasiparticle drift of Landau’s equation with a dissipation governed by a nonlocal and noninstant scattering integral in the spirit of Enskog corrections is derived [1,3]. These corrections are expressed in terms of shifts in space and time that characterize non-locality of the scattering integral. The space shifts parallel finite-diameter corrections to collisions of hard spheres. The time shift is identified as the collision delay [2]. All shifts are given by derivatives of the phase shift in a binary collision [3]. Compared to the BUU- equation, the presented form of virial corrections only slightly increases the numerical demands in implementations. Consequences on current BUU- simulations are discussed and the results for heavy ion simulations are presented [3]. Consequent balance equations for the density, momentum and energy include quasiparticle contributions and the second order quantum virial corrections. The medium effects on binary collisions are shown to mediate the latent heat, i.e., an energy conversion between correlation and thermal energy [4]. This energy conversion is proposed to be of importance to understand the energy balance of recent heavy ion reaction experiments.

[1] V. Špička, P. Lipavský, K. Morawetz, Phys. Rev. B. 55, 5084 (1997); 5095 (1997).

[2] P. Danielewicz and S. Pratt, Phys. Rev. C 53, 249 (1996).

[3] P. Lipavský, K. Morawetz and V. Špička,, Rev. Mod. Phys., (1997), sub.

[4] V. Špička, P. Lipavský, and K. Morawetz, Phys. Lett. A, (1997), sub.