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No description available.

Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Mark A Riley, Florida State University, College of Arts and Sciences, Dept. of Physics. Title and description from dissertation home page (viewed Sept. 21, 2004). Includes bibliographical references.

Ph.D. (Physics) / Please refer to full text to view abstract

Neutron-rich rare-earth nuclei around the maximum of collectivity are predicted to exist with an extremely stable intrinsic configuration in their ground-state structure. Due to the high degree of axial symmetry and large deformation, these nuclei are also excellent candidates for having long-lived high-K isomers. The present work concerns a study of the structure of the yrast bands and a search for isomers in the neutron-rich 68Er isotopes. Excited states of 68Er isotopes were populated via multi-nucleon transfer reactions. A 859 MeV 136Xe-beam was used to bombard a 170Er-target. The experimental setup consisted of the high-resolution γ-ray spectrometer AGATA coupled to the heavy-ion magnetic spectrometer PRISMA. The experiment collected 2 TB of useful data corresponding to 3 days of effective beam time. Beam-like fragments were identified by the PRISMA specrometer placed at the grazing angle of 44 degrees. PRISMA allows for Z, A and q identification as well as TOF and velocity vector determination. This is required for the Doppler correction of the emitted γ rays detected in time coincidence with AGATA. A good Z and very clean A separation has been achieved in PRISMA. Making use of two-body kinematics, Doppler corrected γ-ray spectra for target-like fragments were obtained as well. Due to the novel techniques of PSA and γ-ray tracking, AGATA provided high-quality γ-ray spectra for both beam-like xenon and target-like erbium isotopes. Known yrast bands and isomeric states in neutron-rich erbium isotopes were observed. A candidate for the decay of an isomeric state with Eγ=184 keV  in 173Er, which has no previously known excited states, was identified.