Gamma ray multiplicity set up at the BARC/TIFR 14UD pelletron accelerator

Angular momentum plays an important role in the characterisation of heavy ion reaction processes. Gamma ray multiplicity measurements provide a unique method for the determination of the angular momentum of nuclei produced in heavy ion reactions, and have been used to study the angular momentum distributions in different reaction channels such as transfer, deep inelastic and fusion processes, which have helped in a better understanding of the various aspects of the reaction mechanism in heavy ion collisions. A gamma ray multiplicity array at the BARC/TIFR 14UD pelletron, consisting of a number of hexagonal BGO detector elements has been set up. The salient features of the multiplicity set up, the theory of the measurements and the results obtained from the first experiments using this set up are dealt with. (author). 14 refs., 5 figs