Approximation of reduced width amplitude and application to cluster decay width

Abstract

We propose a simple method to approximately evaluate the reduced width amplitude (RWA) of a two-body spinless cluster channel using the norm overlap with the Brink–Bloch cluster wave function at the channel radius. The applicability of the present approximation is tested for the |$^{16}\hbox {O} + \alpha $| channel in |$^{20}$|Ne as well as the |$\alpha + \alpha $| channel in |$^8$|Be. The approximation is found to be reasonable for evaluating the RWA for states near the threshold energy and it is useful to estimate the |$\alpha $|-decay width of resonance states. The approximation is also applied to |$^9$|Li, and the partial decay width of the |$^6\hbox {He}(0^+_1)+t$| channel is discussed.