Structure of states in 12Be via the 11Be(d,p) reaction

The s-wave neutron fraction of the 0+ levels in 12Be has been investigated for the first time through the 11Be(d,p) transfer reaction using a 5A MeV11Be beam at TRIUMF, Canada. The reaction populated all the known bound states of 12Be. The ground state s-wave spectroscopic factor was determined to be 0.28−0.07+0.03 while that for the long-lived 02+ excited state was 0.73−0.40+0.27. This observation, together with the smaller effective separation energy indicates enhanced probability for an extended density tail beyond the 10Be core for the 02+ excited state compared to the ground state.