Spontaneous emission in symmetrical ion-atom collisions

A general theory of spontaneous electromagnetic emission in symmetrical ion-atom collisions has been developed using a semiclassical adiabatic model of collision. The spontaneous emission probability has been obtained numerically for the p+H case, in an intermediate range of velocities. It has been shown that an earlier suggested quasistatic model of the process works well in a wide range of slow collisions. However, in a range of intermediate collision energies approximately 1 keV the quasistatic cross sections for spontaneous emission may be in error by a factor of 3. The significance of the reported results for plasma applications is emphasized.