Spin dependence of K mixing, strong configuration mixing, and electromagnetic properties of {sup 178}Hf
- Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627 (United States)
- Wright Nuclear Structure Laboratory, Yale University, New Haven, Connecticut 06520 (United States)
- Physics Department, University of Richmond, Richmond, Virginia 23173 (United States)
- GSI, Gesellschaft fuer Schwerionenforschung, Planckstrasse 1, D-64291 Darmstadt (Germany)
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
The combined data of two Coulomb excitation experiments has verified the purely electromagnetic population of the K{sup {pi}}=4{sup +},6{sup +},8{sup -}, and 16{sup +} rotational bands in {sup 178}Hf via 2{<=}{nu}{<=}14 K-forbidden transitions, quantifying the breakdown of the K-selection rule with increasing spin in the low-K bands. The {gamma}-, 4{sup +}, and 6{sup +} bands were extended, and four new states in a rotational band were tentatively assigned to a previously known K{sup {pi}}=0{sup +} band. The quasiparticle structure of the 6{sup +} (t{sub (1/2)}=77 ns) and 8{sup -} (t{sub (1/2)}=4 s) isomer bands were evaluated, showing that the gyromagnetic ratios of the 6{sup +} isomer band are consistent with a pure {pi}(7/2){sup +}[404],{pi}(5/2){sup +}[402] structure. The 8{sup -} isomer band at 1147 keV and the second 8{sup -} band at 1479 keV, thought to be predominantly {nu}(7/2){sup -}[514],{nu}(9/2){sup +}[624] and {pi}(9/2){sup -}[514],{pi}(7/2){sup +}[404], respectively, are mixed to a degree approaching the strong-mixing limit. Based on measured <K{sup {pi}}=16{sup +} parallel E 2 parallel K{sup {pi}}=0{sup +}> matrix elements, it was shown that heavy-ion bombardment could depopulate the 16{sup +} isomer at the {approx}1% level, although no states were found that would mediate photodeexcitation of the isomer via low-energy x-ray absorption.
- OSTI ID:
- 20995121
- Journal Information:
- Physical Review. C, Nuclear Physics, Vol. 75, Issue 3; Other Information: DOI: 10.1103/PhysRevC.75.034308; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
- Country of Publication:
- United States
- Language:
- English
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