Experimental evidence of a component to the 12Be ground state

Data have been obtained on exclusive single neutron knockout cross sections from 12 Be to study its ground state structure. Preliminary cross sections for the first (0.32 MeV, ) and second (1.78 MeV, , unbound ) excited states in 11 Be have been obtained, giving evidence of significant admixtures of both and configurations in the ground state of 12 Be.