Abstract
Associative ionizing molecule-atom collisions Na2(A 1Σ+u) + Na (3p) → Na+3 + e have been observed at simultaneous excitation of dimers and atoms by means of two lasers. Measurements of the relevant ionization current show that the cross section of molecule—atom ionizing collisions exceeds by an order of magnitude the cross section of the well-known atom—atom associative ionization Na(3p) + Na(3p) → Na+2 + e.