Tübingen 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 47: Physik mit schweren Ionen V
HK 47.6: Vortrag
Donnerstag, 20. März 2003, 18:15–18:30, E
Isospin effects in relativistic heavy ion collisions: the role of the isovector scalar channelB — •Th. Gaitanos1,2, V. Baran2,3, M. Di Toro2, V. Greco4, M. Colonna2, and H.H. Wolter1 — 1Univ. Muenchen, 85748 Garching, Germany — 2Laboratorio Nazionale del Sud, Catania, Italy — 3NIPNE-HH, Univ. of Bucharest, Romania — 4Cyclotron Institut and Physics Dep., Texas A-M Univ., College Station
The density dependence of the isovector interaction, i.e. the symmetry energy, in nuclear matter is currently under intense debate, both at densities below and above saturation density. Theoretical models predict widely different behaviour - however, it is of great importance in the physics of neutron stars. The high density behaviour can be investigated in heavy ion collisions between asymmetric (and eventually unstable) nuclei. Here we discuss predictions on signatures of isospin effects from the high density phase in heavy ion collisions. We investigate in particular isospin flow effects, i.e. differences between proton and neutron flow or π+/π− ratios. The investigations are performed with relativistic transport equations employing different parametrizations of the mean field. Besides non-linear and density dependent couplings we investigate the role of the scalar-isoscalar δ-meson, which leads to a stiffer isospin equation-of-state (eos). We see important dynamical effects of the δ-meson, even for the case where the static eos is similar. With such effects it should be possible in future experiments to set constraints on the high density behaviour of the symmetry energy. B Supported by BMBF, contract LM 981