  In this article the history and the current state of research of the
chemiionization processes in atom-Rydberg atom collisions is presented. The
principal assumptions of the model of such processes based on the dipole
resonance mechanism, as well as the problems of stochastic ionization in
atom-Rydberg atom collisions, are exposed. The properties of the collision
kinetics in atom beams of various types used in contemporary experimentations
are briefly described. Results of the calculation of the chemi-ionization rate
coefficients are given and discussed for the range of the principal quantum
number values 5 < n < 25. The role of the chemi-ionization processes in
astrophysical and laboratory low-temperature plasmas, and the contemporary
methods of their investigation are described. Also the directions of further
research of chemi-ionization processes are discussed in this article.
