Fragmentation properties of 6Li

doi:10.1016/0375-9474(87)90626-9

Nuclear Physics A

Volume 474, Issue 2, 23 November 1987, Pages 451-483

https://doi.org/10.1016/0375-9474(87)90626-9 Get rights and content

Abstract

The α+d and t+τ cluster structure of ⁶Li is described in a microscopic α+d cluster model through quantities that enter into the description of cluster fragmentation processes. The states of the separate clusters α, d, t and τ are described as superpositions of 0s Slater determinants belonging to different potential size parameters. The model state space of ⁶Li is a tensor product of the α and d cluster state spaces and the state space of zero-orbital-momentum relative motion, restricted by antisymmetrization. To describe both the ⁶Li and fragment states realistically, we constructed nucleon-nucleon forces optimized for the model state spaces used. The fragmentation properties calculated are the g.s. fragmentation (or reduced-width) amplitudes, their squared Fourier transforms, the corresponding potential overlaps, the spectroscopic factors S_αd, S_tτ and the αd asymptotic normalization constant $C_{αd}$ . The forces constructed reproduce the energies and charge radii of ⁶Li as well as of the fragments excellently. The fragmentation properties predicted by them slightly differ from those calculated with some forces of common use provided the latter are modified so as to reproduce the α, d and ⁶Li energies. The fragmentation properties change moderately in comparison with simpler versions of the cluster model. The full model yields $S_{αd} =0.93, S_{tτ} =0.58 and C_{αd} =3.3$ . The results are consistent with phenomenological estimates except for $C_{αd}$ . The shape of our αd fragmentation amplitudes are in accord with α+p+n three-body calculations but our S_αd and $C_{αd}$ are substantially larger. We attribute this discrepancy to the neglect of the Pauli effects in the usual three-body formula for the αd fragmentation amplitude. We give a formula which contains the necessary remedy.

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Fragmentation properties of 6Li

Abstract

Phys. Lett.

Nucl. Phys.

Phys. Rev.

Phys. Lett.

Z. Phys.

Prog. Theor. Phys.

Ann. of Phys.

Nucl. Phys.

Phys. Rev.

Phys. Rev.

Phys. Lett.

Phys. Rev. Lett.

Phys. Rev.

Phys. Rev. Lett.

Nucl. Phys.

Nuovo Cim.

Prog. Theor. Phys. Suppl.

Prog. Theor. Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Nucl. Phys.

Nucl. Phys.

J. of Phys.

Phys. Lett.

Phys. Lett.

J. of Phys. G8

Z. Phys.

Fiz. Elem. Chastits At. Yadra 8

Sov. J. Part. Nucl.

A unified theory of the nucleus

Fragmentation properties of ⁶Li