Hyperfine interaction as a reason for removing the forbiddenness of a phononless transition in an impurity center
Ellervee' , Laisaar A. I., Oper A. M. A.
Investigation of the influence of the activator's isotopic composition on the intensity of the phononless line in the emission band of CaS-Pb2+ phosphorus, which corresponds to the strongly forbidden ъа iu~>xa lg transition, showed for the first time that this line appears because of hyperfme interaction in an impurity center.