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Initial- and Final-State Alignment and Orientation Effects in Ca Energy Pooling



Harold V. Parks, S R. Leone


An experimental investigation is performed to determine the initial- and final-state alignment effects in the energy-pooling process Ca(4s4p 3P1) + Ca(4s4p 1P1)->Ca(4s4p 1P1)+Ca(4s2). This paper represents a type of four-vector correlation experiment, where two aligned atoms collide and the alignment of the final excited state is observed. The initial Ca(4s4p 3P1) state polarization is controlled with polarized lasers and magnetic fields, and the final-state alignment is partially resolved by observing the polarization of the fluorescence from the Ca(4s4p 1P1)->Ca(4s2) emission. The mathematics are developed in this paper to provide a full quantitative description of the four-vector alignment cross sections observed here. Relative values that describe 18 of the 39 total independent parameters are obtained, obtained, thus defining the results of this collision process at an unprecedented level of detail. The final-state CA polarization is found to be only weakly dependent on the initial-state alignment, with final-state fluorescence predominately polarized along the relative velocity vector of the collision.
Physical Review A (Atomic, Molecular and Optical Physics)
No. 4


alignment orientation, atomic collisions, energy pooling


Parks, H. and Leone, S. (1999), Initial- and Final-State Alignment and Orientation Effects in Ca Energy Pooling, Physical Review A (Atomic, Molecular and Optical Physics) (Accessed December 7, 2023)
Created September 30, 1999, Updated October 12, 2021