FRAGMENTATION OF HIGH MULTIPOLAR VIBRATIONAL STRENGTH IN A SEMICLASSICAL APPROACH

A recent variational approach to the Vlasov equation has shown its ability to describe some splitting of the strength corresponding to nuclear giant resonances, as a consequence of the allowance for rotation Bow. This fragmentation of strength should be understood as a manifestation in a finite system of the phenomenon of Landau damping , which is well-known, for instance, in the electron gas. In this work we extend previous studies, in order to discuss the fragmentation of strength with higher multipolarity. We observe a progressive increase of the fragmentation, so that there are no well-defined collective modes for t > 6 . This conclusion is in anreement with RPA studies, although the loss of coherence for high multipolar modes is not so pronounced in the semiclassical approach as in the quantal case