Inner Hole Excitations in exp 89 Zr and exp 91 Mo Via the ( Exp 3 He, alpha ) Reaction at 97 MeV

摘要

The exp 89 Zr and exp 91 Mo nuclei have been investigated up to approximately 25 MeV excitation energy using the ( exp 3 He, alpha ) reaction at 97.3 MeV incident energy. In addition to the well known low-lying levels and analog states, strongly excited groups of level centered around 4.4 MeV are confirmed to belong to 1f/sub 7/2/ neutron inner shell in exp 89 Zr, with at most approximately 50% of the sum rule strength. A corresponding group, with comparable strength, is found for the first time in exp 91 Mo at nearly the same excitation energy. In addition, and for both nuclei two much smoother structures are observed lying under and beyond the analog states. We discuss their possible attribution respectively to the 1f/sub 7/2/T < missing strength and to 1f/sub 7/2/T > components. Contributions from 1d inner shells are also considered. In both nuclei, new I.A.S. fragments have been identified. (Atomindex citation 12:634150)