POLARIZATION AND ANGULAR-CORRELATIONS IN ATOMIC-COLLISIONS

Polarization and angular correlations in atomic collisions can reveal a wealth of information about the collision dynamics and coherence. Ge neral kinematic analyses of various collision processes are carried ou t in a relativistic helicity formulation. Density matrices are used to describe polarizations of the colliding systems. The complexities in angular momentum couplings are alleviated by employing a graphical app roach. Polarization and angular correlations are presented in concise parametrized expressions in terms of d-functions of rotation matrices. Angle-independent parameters in the expressions provide a convenient classification of dynamic effects and facilitate comparison between th eory and experiment.