OBSERVATION OF TIME-RESOLVED AND ANGLE-RESOLVED PHOTOELECTRON FLUX FROM AN OPTICALLY PREPARED STATE OF A MOLECULE - HYPERFINE DEPOLARIZATION IN NO(A(2)SIGMA(+))

The first measurements of angle-resolved photoelectron flux as a function of the time delay Delta t between excitation and ionization in a molecular (1 + 1') resonance-enhanced multiphoton ionization process are reported. The process studied is NO(X (2) Pi v(g) = 0, J(g) = 2.5) --> NO(A (2) Sigma(+), v = 0, J = 1.5, N = 1) [GRAPHICS] NO+(X (1) Sigma(+), v(+) = 0) in which the intermediate state alignment, and hence the angle-resolved photoelectron signal, evolve as a result of hyperfine depolarization. The results are in good agreement with predictions that use values for the hyperfine coupling constants that have previously been deduced for NO(A (2) Sigma(+), v = 1). This experiment illustrates a general method for the study of intramolecular depolarization mechanisms.