NEW-TYPE OF HIDDEN CROSSINGS IN ATOMIC-COLLISIONS WITH PARTICIPATION OF HIGHLY-CHARGED IONS

We consider the evolution of the branch points of the terms E(R) in th e problem of two Coulomb centers with charges Z(2) and Z(1), when Z(2) much greater than Z(1). In this case we observed a new type of branch points specifically connected with the limit Z(1)/Z(2) --> 0. This le ads to the appearance of a new mechanism of nonadiabatic transitions i n the case Z(2) much greater than Z(1). The limiting positions of the new type of branch points are the branch points of the separation cons tant A(R) for the hydrogenlike atom (Z(2) = Z, Z(1) = 0) in spheroidal coordinates.