Alignment and orientation of H(2p) following excitation in H-He, Ne, Ar collisions

Experimental results for the integral alignment A20 of H(2p) following collisions of hydrogen atoms with helium, neon and argon atoms are presented for projectile energies of 1-5 keV. In addition, the authors have measured as a function of impact parameter the differential (impact-parameter-dependent) alignment and orientation in 2 and 3 keV deuterium-helium collisions. The present results show fair agreement with recent theoretical calculations.