Examine the derivation of Gamows formula for -decay lifetimes, and then derive the equivalent expression for decay

Examine the derivation of Gamow’s formula for α-decay lifetimes, and then derive the equivalent expression for decay by emission of a (small) nucleus of charge z and mass number a. Assume a/A is small enough to ignore recoil. Make sure that the z and a dependence are explicit. Compare your result to anα-decay lifetime with the same Q-value.