An Indirect Measurement of ${}^6$Li(n,$\gamma$) Cross Sections

Abstract

The ${}^6$Li(n,$\gamma$)${}^7$Li cross sections in the neutron energy range of 0.6 to 4 MeV have been measured by the experimental implementation of the direct capture formalism. This was done by measuring the $\gamma$ transition probability experimentally and accounting for the spin factor by theoretical calculation. The electromagnetic transition probabilities from ${}^7$Li${}^{\ast }$ analogous to the initial neutron capture states of ${}^6$Li$+n$ were measured by populating the J${}_i$ states of ${}^7$Li through ${}^7$Li($p,p^{\prime }$)${}^7$Li${}^{\ast }$ reaction. The impact of coupling of resonant states, above neutron separation threshold of ${}^7$Li, in the neutron capture, is observed from the capture $\gamma$ spectrum. The measured cross sections were reproduced through {\sc fresco} and Talys-1.95 Direct Capture Calculations.