Multipole Response of ³He Clusters

Abstract

Ground state properties of normal ³He drops have been studied using either a correlated wave function in conjunction with a realistic potential of Aziz type¹⁾ or a mean-field description based on an effective potential ^2,3). In general, an overall good agreement between both methods has been found. The second one has the advantage of being rather easily applicable to both static and dynamic calculations, although being less fundamental than the first one. In this work we are concerned with the description of the collective modes of normal ³He drops within the self-consistent Random-Phase Approximation (RPA), in which the same effective interaction is used to generate both the mean-field and the residual interaction. We restrict ourselves to surface excitations induced by external multipole fields of r ¹ Y ₁₀ type and to the monopole volume mode generated by the field r ².