High spin states in $\sp{77}$Kr were populated using the $\sp{48}$Ti($\sp{32}$S,2pn)$\sp{77}$Kr reaction with a 106 MeV $\sp{32}$S beam from the Florida State University Tandem-LINAC accelerator. Three Compton-suppressed Ge detectors at 95$\sp\circ$ and one at 18$\sp\circ$ were used to determine $\gamma - \gamma$ coincidences, directional correlation ratios and Doppler-shift attenuation lifetimes. Seven new transitions were added, extending the level scheme to new spin states of (45/2$\sp+$) and 27/2$\sp-;$ twenty-two new lifetimes were measured. High spin states of $\sp{75}$Se were investigated using the $\sp{59}$Co($\sp{19}$F,2pn)$\sp{75}$Se reaction at 55 MeV. Four Compton-suppressed detectors were used in this experiment; three placed at 90$\sp\circ$ and one at 25$\sp\circ$, for the determination of DCO ratios and lifetimes. Spin assignments were confirmed and mixing ratios were determined by measuring angular distributions with the reaction $\sp{71}$Ga($\sp7$Li,3n)$\sp{75}$Se at 25 MeV. Parity assignments were made from polarization measurements using the same reaction. The positive-parity band in $\sp{75}$Se has been extended to $I\sp\pi$ = 29/2$\sp+$ and the unfavored signature band has been identified. The negative-parity band has been extended to $I\sp\pi$ = 19/2$\sp-$. Eleven new lifetimes were measured. A cranking model analysis was performed for both $\sp{77}$Kr and $\sp{75}$Se. A band crossing due to proton alignment was observed for the first time in $\sp{75}$Se. Quadrupole moments extracted from lifetimes, indicated significant collective behavior for both $\sp{77}$Kr and $\sp{75}$Se. The staggering of transition strengths coupled with signature splitting revealed the data to be consistent with largely a triaxial shape for $\sp{75}$Se and a more prolate shape for $\sp{77}$Kr. / Source: Dissertation Abstracts International, Volume: 54-03, Section: B, page: 1462. / Major Professor: Sam Tabor. / Thesis (Ph.D.)--The Florida State University, 1993.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76895 |
| Contributors | Johnson, Timothy Dwight., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 243 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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