An investigation was made of an ionic helium-europium laser of 40 cm3 volume excited by a train of short pulses. A specific output energy 5 Jliter−1 was obtained at an atmospheric pressure of helium and this value was limited by heating of the gas. The charge exchange cross section was determined for the interaction of several ions with an atom of Eu, which resulted in additional population of the other active levels of europium ions when the laser was excited by a beam.