The orientation and alignment parameters in atomic collisions^[1-4] have been actively studied since these phenomena provide detailed information on the mechanism of collisional excitations of target atoms or ions. The electron collisions with ions in nonideal plasmas have received much attention due to many applications using the radiation spectra from the excited ions. The orientation phenomena in plasmas could provide detailed information on plasma parameters.
The orientation phenomena for the 1s → 2p_± collisional excitations in strongly coupled semiclassical plasmas are investigated. In strongly coupled plasma systems, the screening and quantum-mechanical effects play important roles in studies of thermodynamic and kinetic properties of plasmas. Recently, a description of the strongly coupled semiclassical plasmas is provided by the analytic form of the pseudopotential model^[5]taking into account both the quantum effect and also the plasma screening effect is obtained for the interaction potential in strongly coupled semiclassical plasmas. The angular momentum orientation parameter L_⊥ is determined for various Debye length, thermal de Broglie wave length, and collision energy. It is found that the 1s &rarr 2p_-1transitions are strongly favored in all impact parameter regions. The 2p_-1 preference increases with decreasing the thermal de Broglie wave length and decreases with increasing the collision energy. The quantum and screening effects on the orientation parameter increase with increasing the projectile energy. It is also found that the orientation parameters have minima which correspond to the complete 1s → 2p_-1 transition since the 1s → 2p₊₁ transition probability is quite small for small impact parameters.

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