Multipole and relativistic effects in radiative recombination process in hot plasmas.

On the basis of the fully relativistic Dirac-Fock treatment of photoionization and radiative recombination processes with regard to all multipoles of the radiative field, we have assessed the influence of nondipole effects on the radiative recombination rate coefficients. A formula for the rate coefficient has been derived using the relativistic Maxwell-Boltzmann distribution of continuum electrons instead of the commonly used nonrelativistic distribution. This decreases the recombination rate coefficient considerably in hot thermal plasmas.