| Autor: |
F.E. Turner, R. L. Mlekodaj, J. Lin, R. W. Fink, E. H. Spejewski, J. L. Weil, K.S.R. Sastry, G. M. Gowdy, C. R. Bingham, J. L. Wood, J. H. Hamilton, W. D. Schmidt-Ott, L. L. Riedinger, H. K. Carter, A. V. Ramayya, K. J. Hofstetter, B. D. Kern, E. F. Zganjar |
| Rok vydání: |
1976 |
| Předmět: |
|
| Zdroj: |
Physical Review C. 14:1586-1600 |
| ISSN: |
0556-2813 |
| DOI: |
10.1103/physrevc.14.1586 |
| Popis: |
Radioactive sources containing /sup 190/Tl and /sup 190/Hg have been produced and mass separated with the University Isotope Separator on line to the Oak Ridge isochronous cyclotron. Multiscaled spectra of ..gamma.. rays, x rays, conversion electrons, and positrons were obtained, and ..gamma..--..gamma.. and ..gamma..--x-ray coincidences were measured. Two isomers in /sup 190/Tl decay have half-lives of 2.6 +- 0.3 min (2/sup -/) and 3.7 +- 0.3 min (7/sup +/). From ..beta.. decay endpoint energies the 7/sup +/ and 2/sup -/ isomers lie within 0.1 MeV of each other, but which is the ground state was not determined. Both isomers have ground-state Q/sub EC/ values of approximately 7 MeV. The 2/sup -/ level undergoes ..beta.. decay primarily to the 2/sup +/ states at 416.4 and 1099.9 keV in /sup 190/Hg, while the decay of the 7/sup +/ isomer feeds a number of different states with spins ranging from 5 to 9. We observed the 5/sup -/, 7/sup -/, and 9/sup -/ members of the previously identified structure of negative-parity states resulting from coupling of a rotation-aligned i/sub 13///sub 2/ neutron with 3p/sub 3///sub 2/ and 2f/sub 5///sub 2/ neutrons. Some additional states having decays consistent with (6/sup -/) and (8/sup -/)more » assignments perhaps are candidates for less aligned members of the 13/2/sup +/ band coupled with p/sub 3///sub 2/ and f/sub 5///sub 2/ neutrons. The 20-min /sup 190/Hg isotope decays approximately 65% of the time to a level at 171.5 keV, thus making it difficult to study other levels in /sup 190/Au. Four new states in /sup 190/Au were definitely established, while several new ones were suggested by the present work. The populated levels are predominantly low spin and are fairly closely spaced. The log-ft value for the transition to the 171.5-keV level is 5.7, so it is likely that this state has a spin and parity of 1/sup +/. (AIP)« less |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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