Electric quadrupole transitions

Abstract

A data set has been compiled consisting of 101 E2 strengths observed in neutron radiative capture. The E2 strength function is found to be consistent with a fifth power energy dependence and mass dependence characterized by a power of n = 1.87 ± 0.07. The observed strengths are on average consistent with those predicted on the basis of the giant quadrupole resonance. A reduction in strengths is apparent near mass regions 28, 82, and 157. Evidence is cited for the possible existence of a direct capture mechanism.