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DOE OSTI · 1248289

Three-cluster dynamics within an ab initio framework

Quaglioni, Sofia·Romero-Redondo, Carolina·Navratil, Petr
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Abstract

In this study, we introduce a fully antisymmetrized treatment of three-cluster dynamics within the ab initio framework of the no-core shell model/resonating-group method. Energy-independent nonlocal interactions among the three nuclear fragments are obtained from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with bound-state boundary conditions by means of the hyperspherical-harmonic method on a Lagrange mesh. We discuss the formalism in detail and give algebraic expressions for systems of two single nucleons plus a nucleus. Using a soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we apply the method to a 4 He+n+n description of 6 He and compare the results to experiment and to a six-body diagonalization of the Hamiltonian performed within the harmonic-oscillator expansions of the no-core shell model. Differences between the two calculations provide a measure of core ( 4 He) polarization effects.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS

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Quaglioni, Sofia, Romero-Redondo, Carolina, Navratil, Petr. 2013-09-26. Three-cluster dynamics within an ab initio framework. https://doi.org/10.1103/physrevc.88.034320

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