The entrance-channel mass-asymmetry dependence of the compound nucleus formation time in light heavy-ion reactions has been investigated within the framework of semiclassical dissipative collision models. the model calculations have been succesfully applied to the formation of the $^{ 38}$Ar compound nucleus as populated via the $^{ 9}$Be+$^{ 29}$Si, $^{ 11}$B+$^{ 27}$Al, $^{ 12}$C+$^{ 26}$Mg and $^{ 19}$F+$^{ 19}$F entrance channels. The shape evolution of several other light composite systems appears to be consistent with the so-called "Fusion Inhibition Factor" which has been experimentally observed. As found previously in more massive systems for the fusion-evaporation process, the entrance-channel mass-asymmetry degree of freedom appears to determine the competition between the different mechanisms as well as the time scales involved.
Categories: nucl-th