Effects of Isotopic Spin Selection Rules on Photonuclear Yields

Abstract

The effects of isotopic spin selection rules were taken into consideration in order to explain the observed high ratio of ($\ensuremath{\gamma}, p$) to ($\ensuremath{\gamma}, n$) cross sections. The recent experimental evidence on the separate giant resonances for ($\ensuremath{\gamma}, p$) and ($\ensuremath{\gamma}, n$) cross sections seems to support this viewpoint.