Benchmarking $\mathrm{\Lambda }$NN three-body forces and first predictions for A=3-5 hypernuclei

Explicit expressions for the leading chiral hyperon-nucleon-nucleon three-body forces have been derived by Petschauer et al [Phys. Rev. C93.014001 (2016)]. An important prerequisite for including these three-body forces in few- and many-body calculations is the accuracy and efficiency of their partial-wave decomposition. A careful benchmark of the ΛNN potential matrix elements, computed using two robust and efficient partial-wave decomposition methods, is presented. In addition, results of a first quantitative assessment for the contributions of $\mathrm{\Lambda }$NN forces to the separation energies in A=3-5 hypernuclei are reported.