Nuclear Giant Resonances in Coordinate Space - A Semiclassical Density Functional Approach

Abstract

a t f i r s t handicapped by t h e f a c t t h a t t h e ETF f u n c t i o n a l s do n o t apply, i n general, t o s i t u a t i o n s where t h e d e n s i t y i s t i m e dependent, except f o r t h e case o f slow a d i ab a t i c motion.Although some formal progress has been achieved i n the f o u n d a t i o n o f time-dependent d e n s i t y f u n c t i o n a l t h e o r y / 9 / , ready-to-use f u n c t i o n a l s a r e n o t y e t a t hand.I n t h e study o f g i a n t resonances (GR) i t has been r e a l i z e d / l o / t h a t dynamical def o r m a t i o n s o f t h e Fermi sphere i n momentum space, which a r e missed when u s i n g t h e s t a t i c ETF f u n c t i o n a l s /11/, g i v e i m p o r t a n t c o n t r i b u t i o n s t o t h e r e s t o r i n g f o r c e s of some modes (e.g. a l l i s o s c a l a r e l e c t r i c m u l t i p o l e modes w i t h L 3 2 ) . These e f f e c t s , which i n an i n f i n i t e system l e a d t o Landau zero-sound e x c i t a t i o n s , have been i n c o rp o r a t e d t o v a r i o u s degrees of s o p h i s t i c a t i o n i n t h e s o -c a l l e d f l u i d -d y n a m i c a l approach and i t s v a r i a t i o n s /10,12-17/, l e a d i n g t o good agreement w i t h t h e r e s u l t s of RPA c a l c u l a t i o n s and -t o t h e e x t e n t t h a t t h i s i s t h e case f o r t h e RPA r e s u l t s -w i t h experiment. I n many o f these c a l c u l a t i o n s , however, v e r y schematic energy dens i t y f u n c t i o n a l s i g n o r i n g Coulomb and s p i n -o r b i t forces were used; t h e h i g h e r -o r d e r g r a d i e n t c o r r e c t i o n s t o t h e k i n e t i c energy, known t o be i m p o r t a n t t o reproduce c o rr e c t l y s t a t i c n u c l e a r s u r f a c e and d e f o r m a t i o n p r o p e r t i e s / I / , were o m i t t e d , too. Article published online by EDP Sciences and available at http://dx