Fission time scale from pre-scission neutron and α multiplicities in the ~(16)O + ~(194)Pt reaction

摘要

Pre- and post-scission α-particle multiplicities have been measured for the reaction ~(16)O + ~(194)Pt at 98.4 MeV forming ~(210)Rn compound nucleus. α particles were measured at various angles in coincidence with the fission fragments. Moving source technique was used to extract the pre- and post-scission contributions to the particle multiplicity. Study of the fission mechanism using the different probes are helpful in understanding the detailed reaction dynamics. The neutron multiplicities for this reaction have been reported earlier. The multiplicities of neutrons and α particles were reproduced using standard statistical model code JOANNE2 by varying the transient (τ_(tr) ) and saddle to scission (τ_(ssc)) times. This code includes deformation dependent-particle transmission coefficients, binding energies and level densities. Fission time scales of the order of 50-65 ×10~(-21) s are required to reproduce the neutron and α-particle multiplicities.