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

Abstract

We present a calculation for $\eta$ production in the $p{-}^{6}Li$ fusion near threshold including the $\eta {-}^{7}Be$ final state interaction (FSI). We consider the ${}^{6}Li$ and ${}^{7}Be$ nuclei as $\alpha -d$ and $\alpha {-}^{3}He$ clusters respectively. The calculations are done for the lowest states of ${}^{7}Be$ with $J=({\frac{3}{2}}^{-},{\frac{1}{2}}^{-})$ resulting from the $L=$1 radial wave function. The $\eta {-}^{7}Be$ interaction is incorporated through the $\eta {-}^{7}Be$ $T-$matrix, constructed from the medium modified matrices for the $\eta {-}^{3}He$ 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.

Comments: To appear in the proceedings of IVth DAE-BRNS Workshop on HADRON PHYSICS, Aligarh Muslim University, Aligarh, 18-23 Feb. 2008