Thermal Neutron (n,α) Studies in the Rare Earth Region

Abstract

<p>Alpha decay from the thermal neutron capture states in Nd¹⁴³, Sm¹⁴⁹, Sm¹⁴⁷, Gd¹⁵⁵ and Eu¹⁵¹ has been studied. Precise measurements of the thermal neutron (n,α) effective reaction cross sections (σ) and the Q-values for various alpha transitions have been made. Decay schemes have been proposed and a comparison has been made in each case with those obtained by other workers. Experimental values for cross sections were compared with those calculated using the statistical model approach. From the Q-values and cross sections obtained, alpha emission reduced widths have been evaluated.</p> <p>Neutron transmission experiments were made to obtain information on the spins and parities of the capture states in the case of Sm¹⁴⁹. The contribution of bound levels to the neutron capture cross section was confirmed for both Sm¹⁴⁹ and Nd¹⁴³.</p>