Abstract Title: * The rate coefficients of the slow atom-Rydberg atom collisions in geocosmical plasmas Authors: * V. A. SREĆKOVIĆ, M. S. DIMITRIJEVIĆ, Lj. M. IGNJATOVIĆ Institution: * Institute of physics, University of Belgrade, P.O. Box 57 11001, Belgrade, Serbia Preferred format: * poster presentation Abstract Text: * The processes in slow-atom-Rydberg-atom collisions are investigated in this contribution. The calculation of rate coefficients is done for Li and Na for the principal quantum numbers n≥5 and temperatures T≤1000K. The chemi-ionization processes in slow collisions of excited alkali atoms with atoms in ground and excited states were considered, with a particular accent to the applications for geocosmical plasmas. We intend to present the results of calculation of the rate coefficients of the corresponding chemi-ionization processes in the tabulated form easy for further use.