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

Abstract

A model for three composite particles is used to study the ground state of the 6Li nucleus making allowance for the Pauli principle. The relevant wave functions are found by solving a set of two-dimensional Hill-Wheeler integral equations on the quadrature Chebyshev grid. A nonorthogonal many-dimensional gaussian basis was taken to be the expansion basis, so that the wave functions obtained could be presented in the form of a superposition of gaussian functions convenient for applications. Six models (potentials) of the interaction in the NN and Nα subsystems including the central, spin-orbit, and tensor forces are studied. The Coulomb interaction is treated exactly (i.e. not in a perturbative manner). The wave functions obtained are used to analyze a broad spectrum of experimental data, including the 6Li ground state. The applied model, which contains not a single free parameter, has been shown to permit a simultaneous description of the following principal parameters of the 6Li ground state: the binding energy, the rms charge radius, the αd spectroscopic factor, the asymptotic constant of the αd channel, the charge form factor F ch( q 2), the magnetic elastic form factor F M1( q 2) (up to q 2 ≲ 2.5 fm −2), the form factors of the quasielastic scattering reactions ( x, xα) and ( x, xd), and the cross section for the diffractive scattering of protons from the 6Li nucleus with E p = 600 MeV and E p = 1 GeV in a large range of scattering angles.