M1Transition inTl208

Abstract

An attempt is made to explain the abnormally short lifetime of the 40-kev level in ${\mathrm{Tl}}^{208}$. It is shown that although by assuming a certain configuration it is possible to arrive at a coherent contribution to the transition probability from the proton orbital momentum, its magnetic moment, and the neutron magnetic moment, this is not enough to explain the observed lifetime. Configuration interaction can be estimated fairly accurately in this case, and it, too, does not improve the agreement.