A quantum-mechanical formalism to calculate the nuclear excitation by electron transition (NEET) is presented. Emphasis is on the explicit calculations of the transition matrix elements for electric multiple and magnetic dipole NEET and discussions of the selection rules. One of the features of this formalism is that the part of the matrix element in connection with the nuclear partner is related to the nuclear partial radiative width, which is a measurable quantity. This makes it available to evaluate the NEET probability more reliably. The predicted results for NEET probabilities in ${}_{}{}^{189}{}_{}{}^{}\mathrm{Os}$, ${}_{}{}^{197}{}_{}{}^{}\mathrm{Au}$, and ${}_{}{}^{237}{}_{}{}^{}\mathrm{Np}$ are given along with the available measured data.

• Received 2 May 1991

DOI:https://doi.org/10.1103/PhysRevC.44.1910