As we know in Quantum Mechanics,an unstable state remain as a superposition of intial state and decayed state.As long as quantum superposition persist classical exponential decay law is not valid, but much slower t square decay law is valid. After the loss of quantum superposition due to interaction with the environment, the system might be observed in the undecayed state ( dinuclear state) and then classical exponential decay of the undecayed state takes place.
When people try to measure fission time scale, direct measurement like Crystal Blocking or X ray method measures a lifetime ~ 10(-18) sec whereas indirect method like Mass angle correlation study, Neutron multiplicity or GDR multiplicity (where people use different model to predict the fission lifetime) get ~10(-21) sec( much shorter or faster) . We believe this concept of non exponential decay explains the delay observed in direct experiment. Any comments in this regard.
Hello!
Your point seems to me interesting. It is true that in the early stage of the fission pathway (before the necking process occurs) the fission fragments strongly overlap with each other. I also think that binary fission-like events from intermediate systems formed in low-energy heavy-ion collisions may result from different mechanisms (deep-inelastic, quasi-fission and fusion-fission). These span a wide range of time-scales, from 10^-22 to 10^-18 s, which is determined by a number of key variables such as angular momentum, excitation energy of the dinuclear system and the degree of thermal equilibration. The collective potential-energy landscape of the dinuclear system and its dynamics through this landscape is very complex. In my view, the measurements you have mentioned may point out to the different components of the complex yield of binary fission-like products.
Cheers,
Alexis
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