Excitation of multipolar transitions in nuclei by twisted photons

Abstract

The explicit expression for the probability of absorption of a twisted photon by an atomic nucleus has been obtained. It is shown that photoabsorption obeys the selection rule $j⩾|m_{\hat{I}}^3|$, where $j$ is the multipolarity of the nuclear transition, when the nuclei lie near the axis along which a twisted photon with a projection of the total angular momentum $m_{\hat{I}}^3$ propagates. In the long-wave limit, the main contribution to the probability of absorption of a twisted photon comes from the multipole transition with $j=|m_{\hat{I}}^3|$. The absorption coefficient for twisted photons in a target consisting of many nuclei has been found.

15 pp; some misprints corrected