Cross sections, momentum distributions, and neutron angular distributions for Be-11 induced reactions on silicon

The halo neutron breakup cross section for Be-11 on Si has been obtained in a wide energy range by applying an integral method and separately determin ing the contributions of stripping and dissociation mechanisms. a new break up mechanism, for which the core energy is strongly dumped, has also been o bserved. Parallel momentum distributions of Be-10 resulting from breakup ha ve been deduced fur both stripping and dissociation and angular and energy distributions of the neutrons coincident with different reaction products h ave been measured. Charge changing cross sections for Be-10,Be-11 complemen ted the measurements. An extended Glauber model has been elaborated in orde r to provide a unitary interpretation for all the data. It takes into accou nt both the specific structure of Be-11 and the reaction mechanism, practic ally without flee parameters. The effects of reaction mechanisms on the wid ths of observed momentum distributions are particularly important. [S0556-2 813(99)05603-4].