Helicity of orientation parameters of photofragments in fluorescence-imaging experiments

A detection scheme in fluorescence-imaging experiments is presented for determining helicity of orientation parameters of photofragments prepared by circularly polarized photolysis lasers. In a framework of density matrix theory, explicit fluorescence intensity formulas are derived for detection of right- and left-circularly polarized fluorescence photons in various transition sequences. A pattern recognition from fluorescence images of photofragments in a state of definite helicity with respect to their recoil directions has been established, where differences between left- and right-circularly polarized fluorescence image patterns should be taken. Information on the coherence among various magnetic sublevels of an angular momentum state can be obtained by monitoring fluorescence images in a Delta J = -1 transition (P branch in absorption). (C) 1998 American Institute of Physics. [S0021-9606(98)00840-X].