Robustness of the excitation energy at scission as a novel probe of nuclear dissipation at high energy

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In a recent paper [Phys. Rev. C 85, 011601(R) (2012)] we proposed that excitation energy at scission (${E}_{\mathrm{sc}}^{*}$) measured at high initial excitation energy (${E}^{*}$), which can be provided via proton induced spallation reaction approach, is a novel probe of nuclear dissipation ($\ensuremath{\beta}$). The present work is devoted to studying within the framework of the stochastic Langevin model the robustness of the conclusion with respect to the apparent changes in the spin of compound nuclei (CNs), in the magnitudes of the neutron-to-proton ratio of a CN and its fissility and size. In addition, the role of deformation effects as well as the influence resulting from different coefficients applied to deformation-dependent level-density parameters are investigated. All these factors have been found to have important effects on particle multiplicity, evaporation residue cross section, etc., which have widely been used as probes of nuclear dissipation. However, we find that the significant sensitivity of ${E}_{\mathrm{sc}}^{*}$ to $\ensuremath{\beta}$ at high ${E}^{*}$ is little affected by these factors. The result demonstrates that a measurement of ${E}_{\mathrm{sc}}^{*}$ in proton-nucleus reactions can place a robust constraint on the friction strength in the fission process of highly excited nuclei.