Isomeric 17/2^{-} level and parity mixing in ^{93}Tc
نویسندگان
چکیده
isomeric level was measured to be r = 15.2~1.0 p,sec. The level decays by a 39.7-keV E2 branch (73.7+ 1.0%) to the 2145-keV 13/2 level and by a 750.7-keV M2/E3 branch (26.3~1.0%) to the 1434-keV 13/2+ level. An experimental B(E2) [17/2 —F13/2 ] = 11.4~0.9 e'fm is obtained for the E2 branch, impyling an effective charge of e~ = 2.49~0.10. To explore possible parity mixing between the nearly degenerate 17/2 and 17/2+ levels, the precise energy separation of these levels was measured to be 0.44+0.02 keV. On the basis of the observed decay properties, the parity nonconserving matrix element ~(17/2+Jr„~l7/2 )[ was determined -to be less than 0.34 eV.
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