Effects of three-body ΛNN forces in light hypernuclei

Effects of the two-pion-exchange ΛNN force on the binding energies of Λ5He and Λ3H are examined in detail. This ΛNN force W consists of two parts: W = Wp + Ws, where Wp and Ws are due to the p-wave and s-wave π-Λ interaction, respectively. For Wp, the effect of Y1∗ (1385) is also taken into account. For Ws, a suppression factor of the s-wave π-Λ interaction is introduced in analogy to the π-N case. Since we do not know the short-range part of …