Exchange Currents for Hypernuclear Magnetic Moments

Abstract

The meson(K and $π$) exchange currents for the hypernuclear magnetic moments are calculated using the effective Lagrangian method. The seagull diagram, the mesonic diagram and the $Σ^0$-excitation diagram are considered. The $Λ$-N exchange magnetic moments for the ${}^5_ΛHe$, ${}^6_ΛHe$ and ${}^6_ΛLi$ are calculated employing the harmonic oscillator shell model. It is found that the two-body correction is about -9% of the single particle value for ${}^5_ΛHe$. The $π$ exchange current, induced only in the $Σ^0$-excitation diagram, is found to give dominant contribution for the isovector magnetic moments of hypernuclei with A=6.