Dynamic orientation effects on electron-impact excitations in kappa-Maxwellian plasmas

Abstract

The orientation phenomena for the 1s -> 2p(+/- 1) transitions in electron-ion collisional excitations in kappa-Maxwellian plasmas are investigated by using the dynamic interaction potential. The plasma dielectric function in kappa-Maxwellian plasmas is used to obtain the scaled transition probabilities for the 1s -> 2p(+/- 1) excitations. The semiclassical straight-line trajectory approximation is applied to the motion of the projectile electron in order to visualize the variation of the dynamic orientation parameter as a function of the impact parameter, collision energy, projectile energy and spectral index K. It is found that the probability of the m = -1 transition is suddenly increased for 1.5 < K < 2 and is slightly decreased for K > 2 for the small velocity ratio (v/v(parallel to)). It is also found that the probability of the m = -1 transition is decreased for v/v(parallel to) > 2 and increased for v/v(parallel to) > 2. The probability of the m = -1 transition is found to be maximum near the first Bohr radius of the target ion. In addition, the probability of the m = -1 transition is also found to decrease with decreasing Debye length.