Eur. Phys. J. A (2010) 44: 261-277
https://doi.org/10.1140/epja/i2010-10943-9

Regular Article - Theoretical Physics

Three-body structure of low-lying ¹⁸Ne states

¹ Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, Aptdo 1065, ES-41080, Sevilla, Spain
² Department of Physics and Astronomy, Aarhus University, DK-8000, Aarhus C, Denmark
³ Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006, Madrid, Spain

^* e-mail: lay@us.es

Received: 3 December 2009
Revised: 22 February 2010
Accepted: 23 February 2010
Published online: 20 March 2010

Abstract

We investigate to what extent ¹⁸Ne can be descibed as a three-body system made of an inert ¹⁶O core and two protons. We compare to experimental data and occasionally to shell model results. We obtain three-body wave functions with the hyperspherical adiabatic expansion method. We study the spectrum of ¹⁸Ne , the structure of the different states and the predominant transition strengths. Two 0⁺, two 2⁺, and one 4⁺ bound states are found where they are all known experimentally. Also one 3⁺ close to threshold is found and several negative-parity states, 1^-, 3^-, 0^-, 2^-, most of them bound with respect to the ¹⁶O excited 3^- state. The structures are extracted as partial-wave components, as spatial sizes of matter and charge, and as probability distributions. Electromagnetic decay rates are calculated for these states. The dominating decay mode for the bound states is E2 and occasionally also M1 .