Effect of clustering on the emission of light charged particles

. Energy spectra of light charged particles emitted in the reaction p + 27 Al → 28 Si * have been studied and compared with statistical model calculation. Unlike 16 O + 12 C where a large deformation was observed in 28 Si * , the energy spectra of α -particles were well explained by the statistical model calculation with standard “deformability parameters” obtained using the rotating liquid drop model. It seems that the α -clustering in the entrance channel causes extra deformation in 28 Si * in the case of 16 O + 12 C, but the reanalysis of other published data shows that there are several cases where extra deformation was observed for composites produced via non- α -cluster entrance channels also. An empirical relation was found between mass-asymmetry in the entrance channel and deformation, which indicates that along with α -clustering, mass-asymmetry may also affect the emission of a light charged particle.