Cold deformed fission

Fragment mass and charge distributions have been taken for the fission reaction ²³⁵U(n_th,f) both at very high and low fragment kinetic energies. At high kinetic energies cold fission, with virtually no excitation energy being left to the fragments, is by now well established. Rather surprisingly, the fragment characteristics at very low kinetic energies again point to a fragmentation process where at scission the nascent fragments, though heavily deformed, carry no intrinsic excitation. This limiting case of nuclear fission is called cold deformed fission.