Abstract: For calculating integrals involving four confluent hypergeometric functions, a general theoretical method is presented, which is valid for both symmetric and asymmetric geometries to determine the triple differential cross sections (TDCS) for electron impact ionization of ions. The TDCS for the ionization of hydrogenic ion at high and intermediate energies have also been calculated and compared with the existing theoretical results.

Key words: electron impact ionization, ion, triple differential cross sections