Spallation reactions induced by high energy protons: A possible way to probe dissipation in nuclear fission with excitation energy at scission

The stochastic dynamical approach to fission is employed to investigate the influence of initial excitation energy (E*) of Hg compound nuclei (CNs) on its excitation energy at scission (E*(sc)) as a function of nuclear friction strength (beta). It is demonstrated that raising E* can increase the sensitivity of E*(sc) to beta significantly. Moreover, we compare the sensitivity under two contrasting conditions for formed Hg CNs: (i) high E* but low angular momentum l(c) (populated in proton-induced spallation reactions at GeV energies) and (ii) low E* but high angular momentum l(c) (produced through heavy-ion fusion mechanisms). We find that E*(sc) is more sensitive to beta under the conditions of case (i). Our findings suggest that, in experiments, when using E*(sc) to probe nuclear friction, it may be useful to choose the spallation reaction avenue induced by energetic (GeV) protons as a possible way to yield highly excited nuclei.