Low-lying states in Be 12 using one-neutron transfer reaction

A new one-neutron adding reaction on Be11 was performed at 26.9A MeV. The elastic-scattering data was measured simultaneously to determine the target component and optical potentials for the entrance channel. A special isomer-tagging method was used to determine the cross sections for the 02+ state. Based on the ratio of the s-wave spectroscopic factors of the 01+ and 02+ states, along with the previously reported p-wave intensities, the s- and d-wave components of these two states were obtained and compared with shell-model calculations using various interactions. The result shows a dominant d-wave strength in the ground state of Be12, and reveals the dominance of sd- and sp-single-particle configurations in the 2+ and 1- state of Be12, respectively. Together with the configuration mixing analysis, the relative spectroscopic factors, which are shown to be less sensitive to the different choice of optical potentials, provide important insights on the wave functions for the low-lying states of Be12.