Excitation function measurements for disintegrations produced by deuterons in the heavy elements

Abstract

Excitation function measurements have been made for the ( d, p ) reaction in thallium, lead, bismuth and thorium, and also for the ( d, n ) reaction in thallium and bismuth, using deuterons up to 9 MeV energy from the Cavendish cyclotron. The previous results concerning the ( d, p ) reaction in platinum, gold and uranium and the ( d, n ) reaction in gold are also included for purposes of comparison. The energy-yield curves obtained are compared with those to be expected on theoretical grounds. The excitation function for the ( d, n ) reaction is approximately as predicted by the Gamow penetration theory. It is concluded that the Gamow process is responsible for very little if any ot> the yield of the ( d, p ) reaction which occurs mainly by the Oppenheimer-Phillips process. The observed ratio of the ( d, p ) yield to ( d, n ) yield at 9 MeV and its variation with deuteron energy are shown to favour the lower of the two values of the standard nuclear radius, namely, 1.4 x 10 -13 cm. and 2.0 x 10 -13 cm., which have been considered in this paper.