ISSN:
1434-601X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Using the204Hg(α, pn)-reaction andα-particles of energies 39–55 MeV, we have found an isomeric 3.6 min 12− state in206Tl at 2,642.9 keV which has the two-hole configurationπh 11 2/−1 vi 13 2/−1 The 12− state decays mainly by anE5 transition of energy 1,021.4 keV to a 7+ state at 1,621.5 keV whose main configuration isπs 1 2/−1 vi 13 2/−1 There is, in addition, evidence for a weak 565 keVM 4 branch to an 8+ state at 2,078 keV whose main configuration should beπh 11 2/−1 vf 5 2/−1 . The 7+ state decays by a stretched cascade ofγ-rays to states of the following values ofJ π and excitation energy: 5 − + , 1,405.4 keV; 4−, 952.1 keV; 2−, 265.8 keV and 0−, 0 keV. The main configurations of these states areπh 11 2/−1 vp 1 2/−1 ,πd 3 2/−1 vf 5 2/−1 ,πd 3 2/−1 vp 1 2/−1 andπs 1 2/−1 vp 1 2/−1 respectively. From the nuclear masses of208Pb,207Pb,207Tl, and206Tl and the experimental excitation energies it is possible to obtain the proton hole-neutron hole interaction in206Tl. This interaction is compared with the calculations of Kuo and Herling and the discrepancies are discussed. The 12−→8+ M4 transition rate is reduced because of destructive interference between the protonh 11/2→d 3/2 and the neutroni 13/2→f 5/2 contributions. The magnitude of the reduction is accurately reproduced by the wave functions of Kuo and Herling. The 12−→7+ E5 transition rate is about twice as large as the single-holeπh 11 2/−1 πs 1 2/−1 transition rate. This deviation is fully explained by the configuration admixtures in the 7+ state, given by Kuo and Herling.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01409176
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