A single-particle model momentum distribution for⁴He

Abstract

The nucleon momentum distribution for 4He is obtained analytically by means of a single particle (SP) potential which contains both an attractive and a repulsive part. It

Consistent construction of realistic one-body density matrix in nuclei

“…One can expect that this term simulates to some extent the effects of strong repulsion in the nucleon-nucleon interaction at small distances. The single-particle potential (22) had been suggested and used [23,24,25] for the study of charge formfactors and nucleon momentum distributions of light nuclei. One of the main advantages of this potential is that analytical expressions are derived for the single-particle wave functions and for other useful quantities 6 (see e.g., [25]).…”

Correlated charge form factors and densities of the sd-shell nuclei

“…This is a general feature of wave functions with short-range correlations which reproduce theoretical Fon at high momentum transfer better than those obtained with usual single particle potentials. A strong repulsion in the single particle potential may % however ( improve the results considerably (Gibson et al 1968, Grypeos et al 1989.Also, form factors ob tained with wave functions derived from usual Hartee-Fock calculations,are not expected to fit well the experimental Fcn(q) for large values of q (Friedrich et al 1986) .…”

The nucleon momentum distribution in light nuclei

“…The best thing which seems that one can do is to 1Q5 use the "fixed centre of mass correction " [29] which for \He leads to the expression F{q) J,PvF<(o>) (16) The integrations in the above expressions are carried out numerically in our case, which is not so convenient and it is also expected to lead to inaccuracies, in particular at large values of momentum transfers. They are feasible, however, and we have in fact used expression (16) in reporting our first results for \Ht [24]. For heavier nuclei, it is impracticable to use such a procedure in our approach.…”

“…It is usefull to recall that a single-particle wave function (Slater determinant) cannot reproduce simultaneously the charge form factor and the momentum distribution of a correlated system [19]. As our first results for 4 He [24] indicate, however, one might be able to considerably improve the values of tf{k), calculated with an harmonic oscillator single particle wave function, in which the parameters have been fixed by fitting to the experimental charge form factor. This is achieved by suitably modifying the single particle potential.…”