Narrow highly excited states of 9Be

Four narrow levels of 9Be in the 14-18 MeV region are strongly excited in inelastic electron scattering. Two of these are the lowest T=3/2 states and two are positive-parity states. Previous shell-model attempts to fit the measured transverse form factors were unsuccessful for the T=3/2 levels and assumed structures for the positive-parity states that were inconsistent with their high excitation energies and narrow widths. We show that improved fits to the T=3/2 form factors can be obtained by using alternative p-shell interactions, and that arguments given previously for including higher configurations are suspect. A better description of the positive-parity states is obtained when they are assumed to have large parentage amplitudes with the 2+, T=1 and second 2+, T=0 states rather than the ground state of 8Be. The observed 16.671 MeV level is identified as 5/2+, T=1/2 and the 17.493 MeV level as 7/2+, T=1/2. (orig.)