Abstract
Multiple emission of intermediate-mass fragments has been studied for the collisions of p,
4He and
12C on Au with the 4
π setup FASA. In the case of
12C(22.4 GeV)
+
Au and
4He(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
12C
+
Au collisions).