DISTRIBUTION OF ELECTRONS IN DOUBLE PHOTOIONIZATION OF HELIUM AND HEAVIER ATOMS IN THE ASYMPTOTIC REGION

This paper presents an analysis of the energy distribution of the outg oing electrons in the double ionization of helium by photons with ener gies much larger than the ionization potential. The analysis improves on the one carried out by Amusia et al. [J. Phys. B 8, 1248 (1975)] in the framework of the special model for the wave function of helium. N ow the energy distribution is expressed through certain expectation va lues averaged over the initial state described by the wave function of the general form Psi(r(1),r(2)) A larger interval of values of photon energies is considered. The limit equations for the angular distribut ion are obtained. The general features of the process with heavier ato ms are also analyzed.