Deviations from pure target fragmentation in 94A MeV 16O induced heavy ion reactions

The emission of low energy, 1 A –6 A MeV, medium size, Z =3–12, fragments in 16 O + 27 Al reactions at 94 A MeV has been studied. In addition to a fragmentation component with ∼ 15 A MeV/ c parallel- and transverse momentum shifts, another component with larger momentum width is needed to describe the results. An attempt to use the VUU prescription indicates that secondary decay from excited primary fragments is important.