Nuclei in the light rare-earth, for values of N ≥ 90, are textbook examples of the evolution of nuclear structure with respect to
excitation energy and angular momentum in deformed nuclei. In the high-spin region (J ≥ 10ħ), effects such as backbends and shape changes occur,
ending with termination of the lower energy collective structures. First backbends occur before 20ħ Findings also reflect a spectacular return
to collectivity in the "ultra-high spin" region (J ≥ 50ħ). Thanks to recent developments in both detectors and accelerators, gamma-ray
spectroscopy has been able to probe the upper ends of the high-spin region, and begin probing into the ultra-high spin regime. Data from two
experiments form the basis of this work. One study was an ultra-high-spin analysis of the Z=67, N=90 ¹⁵⁷Ho nucleus at Argonne National
Laboratory with Gammasphere. The findings were that remarkable correlations were observed to the neighboring isotone, ¹⁵⁸Er, in which
termination states and ultra-high spin structures had been previously observed. A high-spin investigation of Ytterbium (Yb) and Erbium (Er)
isotopes was performed at FSU. This study used an intense radioactive ¹⁴C beam, available at FSU, in order to study these heavy, neutron-rich
nuclei in regions of angular momentum and excitation energy not attainable with stable beams. The reactions of ¹⁷⁰Er(¹⁴C,5n/4n/α4n) generated
new information in ¹⁶⁹Yb, ¹⁷⁰Yb, and ¹⁶⁶Er, respectively. Due to the recently upgraded digital FSU Gamma-Ray Array, aided by JBSMILE, triple
ᵧ-ray coincidences were able to be viewed in these nuclei for the first time at FSU. The result was the investigation of rotational alignments
in both the yrast and non-yrast multi-quasiparticle bands in these nuclei. / A Dissertation submitted to the Department of Physics in partial fulfillment of the requirements for the degree
of Doctor of Philosophy. / Fall Semester 2018. / November 19, 2018. / Includes bibliographical references. / Mark A. Riley, Professor Directing Dissertation; Oliver Steinbock, University Representative; Samuel L.
Tabor, Committee Member; Alexander Volya, Committee Member; Laura Reina, Committee Member.
Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_661187 |
Contributors | Baron, Jonathan S. (author), Riley, Mark A. (professor directing dissertation), Steinbock, Oliver (university representative), Tabor, Samuel L. (committee member), Volya, Alexander (committee member), Reina, Laura (committee member), Florida State University (degree granting institution), College of Arts and Sciences (degree granting college), Department of Physics (degree granting departmentdgg) |
Publisher | Florida State University |
Source Sets | Florida State University |
Language | English, English |
Detected Language | English |
Type | Text, text, doctoral thesis |
Format | 1 online resource (133 pages), computer, application/pdf |
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