On the time-scale of quasifission and Coulomb fission

The Coulomb fission may take place in a reaction if the maximum excitation energy transfer exceeds barrier of either projectile or target nucleus. This condition is satisfied all reactions used for earlier blocking measurements time-scale except $$^{208}\hbox {Pb}~+$$ natural Ge crystal, where below measurement limit technique $$<1$$ as. Inclusion data analysis experiments leads us to interpret measured time-scales longer than few attoseconds (as) (about 1–2.2 as) due slow and those shorter 1 as, as quasifission fast fission. Consequently, this finding resolves critical discrepancies between using nuclear techniques. This, turn, validates fact that are indeed order zeptosecond (zs) accordance with theories. present results thus provide an essential input understanding fusion evaporation during formation heavy elements.