Theoretical consideration of a twisted atom

We investigate the twisted state of an atom and the possible effect of such a state on the properties of the photons emitted as a result of an electron transition in that atom. We first propose a framework for describing the twisted atomic state and then explore possible differences in the nuclear recoil effects in the twisted atom compared to those in the plane-wave atom. We conclude that if the initial atomic state is twisted, then the photon distribution is altered. We point out that, in a certain observation scheme, one can detect a feature of this twist in the distribution of the emitted photons, even in zero order in $m/M$.