Saturation of the width of the giant dipole resonance at high excitation energies

Abstract

Gamma-ray energy spectra have been measured for the 16O + 118Sn reaction at incident beam energies of 200 and 280 MeV. Comparing the experimentally obtained spectra with statistical-model calculations shows that the width of the isovector giant dipole resonance saturates beyond excitation energies of 165 MeV in the compound nucleus.