Analytical approach to electromagnetic processes in loosely bound nuclei: application to 8B

Abstract

In this paper we develop an analytical model in order to study electromagnetic processes involving loosely bound neutron-rich and proton-rich nuclei. We construct a model wave function, to describe loosely bound few-body systems, having the correct behaviour both at large and small distances. The continuum states are approximated by regular Coulomb functions. As a test case we consider the twobody Coulomb dissociation of 8 B and, the inverse, radiative capture reaction. The difference between using a pure two-body model and the results obtained when incorporating many-body effects, is investigated. We conclude that the interpretation of experimental data is highly model dependent and stress the importance of measuring few-body channels.

Radiative capture and electromagnetic dissociation involving loosely bound nuclei: The8Bexample

“…Let us first compare our analytical two-body (dotted line) and three-body (solid line) results, see also Ref. [5]. Concerning the shape of the energy spectrum we have an excellent agreement between the experimental data and our results obtained using the three-body model, while the pure two-body calculation gives a too narrow peak.…”

“…In this paper we have studied electromagnetic processes involving loosely bound nuclei. To this aim we have developed an analytical model which is based on the use of radial model functions that give a realistic description of two-body WFs (or the two-body projections of many-body WFs) for all radii, see also [5]. We have used this model to study EMD of 8 B, but have also indicated how it can be applied to other reactions and other nuclei.…”

“…This question is of great significance for the gathering of information on astrophysically interesting radiative capture reactions from EMD experiments (note the relation between the E1 component of the EMD energy spectrum and the astrophysical S-factor via Eqs. (4)(5)(6)). The main method so far has been to study the asymmetries in angular or momentum distributions.…”

“…Our approach will be general in the sense that both neutron-rich and proton-rich systems can be studied. This model was first presented in [5] while similar approaches also exist for one-neutron [6,7] and two-neutron [8][9][10] halo nuclei. Although advanced numerical investigations are readily performed utilizing present day computer power, an analytical approach might have an advantage when exploring general physics features, and the sensitivity to different model assumptions.…”