Transition from Thermal to Rapid Expansion in Multifragmentation of Gold Induced by Light Relativistic Projectiles
arXiv:nucl-ex/0102007 · doi:10.1016/S0370-2693(01)00227-1
Abstract
Multiple emission of intermediate-mass fragments has been studied for the collisions of p, $^4$He and $^{12}$C on Au with the $4Ï$ setup FASA. In the case of $^{12}$C(22.4 GeV)+Au and $^4$He(14.6 GeV)+Au collisions, the deviations from a pure thermal break-up are seen in the energy spectra of the emitted fragments: the spectra are harder than calculated and than measured in p-induced collisions. This difference is attributed to a collective flow with the expansion velocity on the surface about 0.1 $c$ (for $^{12}$C+Au collisions).
12 pages, 3 figures, accepted in Phys. Lett. B