Study of the $\eta-^7Be$ Interaction Near Threshold in $p-^6Li$ Fusion

TL;DR

This paper models the near-threshold $ ext{eta}$ production in $p-^6Li$ fusion, emphasizing the $ ext{eta}-^7Be$ final state interaction using cluster models and medium-modified few-body equations.

Contribution

It introduces a detailed calculation of $ ext{eta}-^7Be$ interactions near threshold, incorporating medium effects and cluster structures, which is a novel approach in this context.

Findings

The $ ext{eta}-^7Be$ interaction significantly influences near-threshold production.

Medium modifications alter the $ ext{eta}$-nucleus scattering properties.

The model predicts observable effects in fusion reactions involving light nuclei.

Abstract

We present a calculation for $\eta$ production in the $p-^6Li$ fusion near threshold including the $\eta-^7Be$ final state interaction (FSI). We consider the $^6Li$ and $^7Be$ nuclei as $\alpha-d$ and $\alpha-^3He$ clusters respectively. The calculations are done for the lowest states of $^7Be$ with $J = ({3\over2}^-, {1\over2}^-)$ resulting from the $L = $1 radial wave function. The $\eta-^7Be$ interaction is incorporated through the $\eta-^7Be$ $T-$matrix, constructed from the medium modified matrices for the $\eta-^3He$ and $\eta-\alpha$ systems. These medium modified matrices are obtained by solving few body equations, where the scattering in nuclear medium is taken into account.