Effects of barion correlation and core deformation in hypernuclear three-, four-, and five-particle systems

Based on the direct three-, four-, and five-particle variation calculations of the 3$_\Lambda^3\rm H$, $_\Lambda^4\rm H$, $_\Lambda^4\rm H^*$, $_\Lambda^4\rm He$, $_\Lambda^4\rm He^*$ and $_\Lambda^5\rm He$ hypernuclei and also of the $^2\rm H$, $^3\rm H$, $^3\rm He$ and $^4\rm He$ nuclei, the effects of particle correlation as well as the core contractivity are investigated, and the conditions of applicability of the two-body ($\Lambda+{}$остов) model of hypernuclei are discussed.