Nondipole effects in the angular distribution of photoelectrons in two-photon two-color above-threshold atomic ionization

Expressions for the angular distribution of photoelectrons produced in two-photon two-color atomic ionization are obtained within the statistical tensor formalism, taking into account a full multipole expansion of the radiation in electric and magnetic moments. The general expressions are reduced to a simpler form for a particular geometry used in experiments with XUV + optical radiation beams and analyzed within the first-order nondipole corrections for different polarization states of the photons. As a numerical example, the Ne 1s above-threshold ionization by two-color radiation is considered within the second-order perturbation theory. A large forward-backward asymmetry in the photoelectron angular distribution is predicted.