THE ADIABATIC MECHANISM OF THE COLLISIONAL BROADENING OF RYDBERG STATES VIA A LOOSELY BOUND RESONANCE STATE OF AMBIENT GAS ATOMS

The adiabatical mechanism of the oscillations of the broadened cross sections produced by collisions of Rydberg alkali atoms with ground-state atoms of an ambient alkali gas is presented. The dependence of the oscillations of the cross sections on the principal quantum number n arises due to the oscillations of the mixing parameter for the pseudocrossing between the 3P ion state energy curve of the ambient gas atom and the Rydberg state dependent on n. The latter oscillations are generated by the oscillations of the Rydberg electron wavefunction in the coordinate space. The numerical results obtained are in good agreement with the experimental data for different colliding pairs. The matching of the adiabatical picture and the conventional impulse approximation is discussed.