Nuclear viscosity of hot rotating 240 Cf

Abstract

In a detailed investigation of giant dipole resonance (GDR) γ-ray yield from 240Cf populated in the 32S + 208Pb reaction, the absolute γ-ray/fission multiplicities are extracted over a wide range of excitation energy and angular momentum. The enhanced yield of GDR decay γ rays has been analyzed within the framework of a modified statistical model containing the nuclear viscosity as a free parameter. The extracted nuclear dissipation coefficient is found to be independent of the temperature. Large constant dissipation during the saddle-to-scission path provides good fits to the γ-ray spectra.