Detailed study of the cluster structure of light nuclei in a three-body model: (III). Electromagnetic structure of 6Li

Abstract

The multicluster dynamic model with the Pauli projection (MDMP) for treating light nuclei, developed earlier, is used to study in detail the 6Li electromagnetic structure including all the measured elastic and inelastic, transverse and longitudinal, isoscalar and isovector electromagnetic form factors of the nucleus and to make some predictions concerning other, not yet measured, form factors. The model is also used to calculate all the measured radiation widths Γ γO of the excited 6Li * states. A proper description has been obtained for most of the known electromagnetic form factors of the nucleus. The reasons for disagreement with experimental data in the case of large momentum transfers in the M1 form factors, both elastic and inelastic, are discussed. The elastic CO form factor of 6Li and, probably, of other light nuclei in the region of the secondary maximum is shown to be defined, to a very great extent, by the behaviour of the α-particle charge form factor in the region of its secondary maximum. The radiation widths of the 3 +0, 2 +0, and 1 +0 levels have been found to be highly sensitive to minor impurities of the wavefunction components with higher orbital moments for the excited states, as well as the ground state, of 6Li. The Siegert theorem is shown to be of great importance when studying the probabilities of transverse electromagnetic transitions. The copious results obtained by the present authors, as well as elsewhere, concerning the diverse aspects of the behaviour of six-nucleon system in the strong, weak, and electromagnetic processes are used to formulate the concept of using the given system as an extremely convenient theoretical laboratory in nuclear physics. The relevant proposals concerning future experiments are formulated.