Document Type
Article
Publication Date
8-2014
Department 1
Physics
Abstract
The neutron decay of an unbound resonance in 12Be has been measured at 1243 ± 21 keV decay energy with a width of 634 ± 60 keV. This state was populated with a one-proton removal reaction from a 71 MeV/u 13B beam incident upon a beryllium target. The invariant mass reconstruction of the resonance was achieved by measuring the daughter fragment in coincidence with neutrons. Despite being above the 2n separation energy, the state decays predominantly by the emission of one neutron to 11Be, setting an upper limit on the branching ratio for the two-neutron decay channel to 10Be of less than 5%. From the characteristics of the population and decay of the resonance, it is concluded that this state cannot correspond to the previously observed state at 4580 ± 5 keV.
Copyright Note
This is the publisher's version of the work. This publication appears in Gettysburg College's institutional repository by permission of the copyright owner for personal use, not for redistribution.
DOI
10.1103/PhysRevC.90.024309
Recommended Citation
Smith, J.K., et al. "Low-lying neutron unbound states in 12Be." Physical Review C 90.2 (August 2014), 024309.
Required Publisher's Statement
Original version is available from the publisher at: https://journals.aps.org/prc/issues/90/2