The level structures of $\sbsp{61}{144}$Pm$\sb{83}$ and $\sbsp{61}{145}$Pm$\sb{84}$ were investigated using heavy-ion reactions and the techniques of $\gamma$-ray and electron spectroscopy as well as transfer reactions. Decay schemes were constructed from prompt $\gamma$-$\gamma$-coincidence, delayed $\gamma$-$\gamma$-coincidence, excitation function, angular distribution and conversion electron measurements of the $\sp{19}$F + $\sp{130}$Te fusion-evaporation reaction at beam energies between 70 and 85 MeV. / A total of 53 new transitions and 31 new levels were placed in $\sp{144}$Pm. The level scheme extends to spin $J=20\hbar$ and an excitation energy of 5.8 MeV. Transitions feeding the 841 keV ($J\sp\pi=9\sp+$) isomeric state were observed for the first time. The reduced $B(E3)$ transition strength for the 669 keV ($9\sp+\to 6\sp-$) transition deexciting this state was determined to be 3.2(7) Weisskopf units, supporting the interpretation of the 9$\sp+$ level as a ($\pi 1h\sb{11/2}\otimes\nu 2f\sb{7/2}$) non-collective state. / Nineteen new levels connected by 32 new transitions extended the decay scheme of $\sp{145}$Pm up to a tentative spin of (${33\over 2})\hbar$ and an excitation energy of 4.7 MeV. The ${11\over 2}\sp-$ isomeric state at 795 keV was identified as a single $h\sb{11/2}$ proton state in the $\sp{144}$Nd($\sp7$Li,$\sp6$He) stripping reaction at a beam energy of 34 MeV. A measurement of the $B(E3)$ reduced transition strength (7.8(18) Weisskopf units) of the 795 keV (${11\over 2}\sp-\to{5\over 2}\sbsp{\rm g.s.}{+}$) transition deexciting this state supports this interpretation. A weak coupling model can explain the structure of the deduced decay scheme up to an excitation energy of 2.5 MeV. / The spectroscopy of $\sp{144}$Pm and $\sp{145}$Pm is discussed in terms of couplings of single-particle states to a $\sp{146}$Gd core using empirical shell-model calculations. Good agreement with the experimental results is obtained. / Source: Dissertation Abstracts International, Volume: 53-10, Section: B, page: 5262. / Major Professor: Paul D. Cottle. / Thesis (Ph.D.)--The Florida State University, 1992.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76779 |
| Contributors | Glasmacher, Thomas., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 155 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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