Tunneling limit in the theory of photoelectron rescattering by the parent ion

A generalized Keldysh model is used to obtain simple analytical expressions for the energy and angular distributions of photoelectrons rescattered by the parent ion. The dependence of the form, absolute magnitude, and interfe rence structure of the distributions on the parameters of the field and ato m is investigated. It is shown that even though the semiclassical three-ste p rescattering model determines correctly the position of the boundaries be yond which the distributions decay rapidly, the model itself is inapplicabl e near them. (C) 2000 MAIK "Nauka/Interperiodica".