Effect of a D-state admixture in the alpha particle on the B Lambda value of Lambda 5He.

Abstract

We have calculated the ${B}_{\ensuremath{\Lambda}}$ value of $_{\mathrm{\ensuremath{\Lambda}}}^{5}\mathrm{He}$ within the framework of the resonating group method using antisymmetrized \ensuremath{\alpha}+\ensuremath{\Lambda} cluster wave functions and two different effective \ensuremath{\Lambda}N interactions. Differing from previous studies, we allow the \ensuremath{\alpha} particle to have a nonvanishing D-state admixture. We find that the presence of a D-state component reduces the ${B}_{\ensuremath{\Lambda}}$ value. Depending on the strength of the D-state admixture, which we adopt from theoretical predictions or analyses of experimental data, we calculate a reduction of the ${B}_{\ensuremath{\Lambda}}$ value of 150--505 keV for the Minnesota \ensuremath{\Lambda}N interaction and of 80--270 keV for the effective \ensuremath{\Lambda}N force of Yamamoto and Bando.