Energy and polarization dependence of chemi-ionization processes inK(42 P 3/2)−K(42 P 3/2) collisions

Using crossed molecular beams we have investigated ionizing collisions between potassium atoms in their 4² P _3/2-states, leading to the exit channelsK ₂ ⁺ +e ^?,K ⁺+K ^?, andK(4² S _1/2)+K ⁺+e ^?, respectively. Measurements of the total ionization cross section as well as of the cross sections for the individual channels are reported as a function of both the relative collision energy (0.2 to 2.4 eV) and the angle between the electric field vector of the exciting laser light and the relative velocity vector. The results are interpreted in terms of the molecular states of theK ₂ ^* quasi molecule which are involved in the ionization process.