Magnetic field effects on cross section of inelastic electron-ion collisions

The magnetic field effects on the cross section of inelastic electron-ion c ollisions on 1s --> 2p dipole transition of hydrogenic ions are calculated. An atmospheric pressure plasma in thermodynamic equilibrium imbedded in an external, constant, and homogeneous magnetic field is considered. The magn etic field and plasma screening effects on the bound states of hydrogenic i on are included. The longitudinal dielectric function for magnetoactive pla smas is used to describe the interaction potential. The semiclassical strai ght-line trajectory approximation is used to the motion of the projectile e lectron. The partial cross section of electron-impact excitation of hydroge nic ions is derived as a function of the impact parameter, projectile energ y, Larmor frequency, and plasma parameters. The scaled partial cross sectio n of the electron-impact excitation including the magnetic field effect is always smaller than one without the magnetic field. When the Larmor frequen cy increases, the magnetic field effect decreases. For larger projectile ve locity the differences between the partial cross section of electron-impact excitation for different magnitude of magnetic field becomes more signific ant. (C) 2001 American Institute of Physics.