Measurement of the Survival Probabilities for Hot Fusion Reactions

Abstract

We have studied the fission-neutron emission competition in highly excited ${}^{274}$Hs (Z=108) (where the fission barrier is due to shell effects) formed by a hot fusion reaction. Matching cross bombardments (${}^{26}$Mg + ${}^{248}$Cm and ${}^{25}$Mg + ${}^{248}$Cm) were used to identify the properties of first chance fission of ${}^{274}$Hs. A Harding-Farley analysis of the fission neutrons emitted in the ${}^{25,26}$Mg + ${}^{248}$Cm was performed to identify the pre- and post-scission components of the neutron multiplicities in each system. ($\Gamma$${}_n$/$\Gamma$${}_t$) for the first chance fission of ${}^{274}$Hs (E${}^{\ast }$ = 63 MeV) is 0.89 $\pm$ 0.13, i.e., $\sim$ 90 of the highly excited nuclei survive.The high value of that survival probability is due to dissipative effects during de-excitation. A proper description of the survival probabilities of excited superheavy nuclei formed in hot fusion reactions requires consideration of both dynamic and static (shell-related) effects.

Cited by in corpus (5)

• Time-dependent Hartree-Fock plus Langevin approach for hot fusion reactions to synthesize the $Z=120$ superheavy element
• Sub-barrier enhancement of fusion as compared to a microscopic method in 18O+12C
• Uncertainties and understanding of experimental and theoretical results regarding reactions forming heavy and superheavy nuclei
• Quest for consistent modelling of statistical decay of the compound nucleus
• Towards microscopic studies of survival probabilities of compound superheavy nuclei