ΔEγ=30keV ridge observed in the37Cl+120Sn reaction

The ridge structure at {Delta}E{sub {gamma}}={plus_minus}30 keV, observed previously in the reaction 187 MeV {sup 37}Cl + {sup 120}Sn and attributed to an hyperdeformed nuclear shape, has been studied in a high statistics proton-{gamma} coincidence experiment. The presence of the ridge is confirmed but it is correlated to a set of {gamma}-ray energies different from those proposed in earlier works. Some discrete transitions associated with this structure, which accounts for only {approximately}3{times}10{sup {minus}5} of the fusion evaporation cross section, are proposed. {copyright} {ital 1997} {ital The American Physical Society}