Eur. Phys. J. A (2012) 48: 24
https://doi.org/10.1140/epja/i2012-12024-7

Regular Article - Theoretical Physics

Leading E1 and M1 contributions to radiative neutron capture on lithium-7

¹ Department of Physics & Astronomy and HPC2 Center for Computational Sciences, Mississippi State University, 39762, Mississippi State, MS, USA
² Kernfysisch Versneller Instituut, Theory Group, University of Groningen, 9747AA, Groningen, The Netherlands
³ Instituto de Física, Universidade de São Paulo, C.P. 66318, 05314-970, São Paulo, SP, Brazil

^* e-mail: nkf22@msstate.edu

Received: 18 October 2011
Revised: 23 December 2011
Accepted: 25 January 2012
Published online: 29 February 2012

Abstract

Using halo effective field theory, we provide a model-independent calculation of the radiative neutron capture on lithium-7 over an energy range where the contribution from the 3⁺ resonance becomes important. We also present power counting arguments that establish a hierarchy for electromagnetic one- and two-body currents. One finds that a satisfactory description of the capture reaction, in the present single-particle approximation, requires a resonance width about three times larger than the experimentally quoted value.