The impact parameter and isospin dependence of the disappearance of flow

✍ Scribed by Gary D. Westfall

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 657 KB
• Volume: 630
• Category: Article
• ISSN: 0375-9474
• DOI: 10.1016/s0375-9474(97)00741-0

✦ Synopsis

The disappearance of collective transverse flow can be related to the nuclear equation of state and in-medium nucleon-nucleon scattering. Experimental and theoretical results from several groups are presented for collisions of Ar+Sc, Ar+A1, Zn+A1, 5SFe+SSFe, ~SNi+SSNi, and SSMn+SSFe and incident energies ranging from 35 to 155 MeV/nucleon. By comparing experimental results for the balance energy with predictions from transport models, one can show that the description of the nuclear mean field must include momentum dependence. The balance energy can be shown to depend on the in-medium cross sections using transport models. A model independent verification of this dependence has been done experimentally by varying the N/Z of the system while holding all other parameters constant. The balance energy changes with the isospin of the system in qualitative agreement with a transport model incorporating isospin dependent nucleon-nucleon scattering and mean field.