Theoretical cross sections for alignment destroying collisions in the 2p levels of neon

Abstract

The impact theory is used to calculate the cross sections for the destruction of alignment of excited neon atoms in the levels of the 2p⁵3p configuration by collisions with ground state helium or neon atoms. The interatomic force is assumed to be due to the electrostatic dipole-dipole interaction. The results are compared with experimental values. There is good numerical agreement for depolarization by neon but for helium perturbers the theoretical values are smaller by a factor of two than the experimental values. The detailed comparison of the experimental and theoretical results suggests that for collisions with helium and neon atoms the repulsive part of the potential is important and that the deviation of the colliding particles from straight line paths should also be taken into account in the theory.