Inhibition of the Fission Decay Channel of the Isoscalar Giant Quadrupole Resonance in the Actinide Region

Abstract

A measurement of the fission probability of the isoscalar giant quadrupole resonance, excited by inelastic scattering of 120-MeV $\ensuremath{\alpha}$ particles, yields an upper limit of 0.01 for the fission probability of the isoscalar giant quadrupole resonance in $^{232}\mathrm{Th}$, compared to 0.055\ifmmode\pm\else\textpm\fi{}0.015 for the underlying continuum.