Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HK: Physik der Hadronen und Kerne

HK 47: Heavy Ions VI

HK 47.2: Gruppenbericht

Donnerstag, 14. März 2002, 16:30–17:00, E

Au + Au collisions at 40 to 150 A MeV studied with INDRA — •Jerzy Lukasik — GSI Darmstadt, Planckstr. 1, D-64291 Darmstadt

The emission of intermediate-mass fragments in collisions of ¹⁹⁷Au on ¹⁹⁷Au has been systematically studied over the range of incident energies from 40 to 150 A MeV using the 4π-multidetector INDRA and beams from the heavy-ion synchrotron SIS at GSI. The analysis was performed as a function of incident energy and of impact parameter, defined through the total transverse energy of light charged particles (Z≤2).

In more peripheral collisions, strong forward-backward asymmetries in the emission patterns with respect to the excited projectile and target-like fragments are observed and interpreted in the framework of statistical multifragmentation and molecular dynamics models. The transverse-velocity spectra of intermediate mass fragments produced at mid-velocity are found to show an intriguing invariance with respect to the incident energy which may be related to the role of Pauli blocking.

In central collisions, the onset and rapid rise of collective radial flow has been observed. The considerable anisotropies in the flow pattern along the beam direction are interpreted within the statistical multifragmentation model which has been modified to allow for source deformation and collective motions.