2014/04/07 by C. Romero-Redondo, Carolina Romero-Redondo, Sofia Quaglioni +3 · 2 citations
Physics and Astronomy · #Advanced Chemical Physics Studies #Atomic and Molecular Physics #Nuclear physics research studies #nucl-th
paper · pdf · doi:10.1103/physrevlett.113.032503
published as Phys. Rev. Lett. 113, 032503 (2014) · 5 pages 4 figures
arxiv created 2014/04/07 · openalex publication_date 2014/07/16 · arxiv updated 2014/07/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The low-lying continuum spectrum of the (6)He nucleus is investigated for the first time within an ab initio framework that encompasses the (4)He + n + n three-cluster dynamics characterizing its lowest decay channel. This is achieved through an extension of the no-core shell model combined with the resonating-group method, in which energy-independent nonlocal interactions among three nuclear fragments can be calculated microscopically, starting from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with three-body scattering boundary conditions by means of the hyperspherical-harmonics method on a Lagrange mesh. Using a soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we find the known J(π) = 2(+) resonance as well as a result consistent with a new low-lying second 2(+) resonance recently observed at GANIL at 2.6 MeV above the (6)He ground state. We also find resonances in the 2(-), 1(+), and 0(-) channels, while no low-lying resonances are present in the 0(+) and 1(-) channels.