DISSOCIATION DYNAMICS OF QUASI-BOUND LEVELS IN THE G(3)SIGMA(-2 - CHARACTERIZATION OF THE CONTINUUM()(G) STATE OF H)

Decay pathways and photofragment anisotropy parameters have been deter mined for a series of rovibrational levels of the g (3) Sigma(g)(+) st ate in molecular hydrogen using fast-beam photofragment spectroscopy. The g (3) Sigma(g)(+)(upsilon=4) levels are found to be weakly prediss ociated by homogeneous interaction with the lower lying n=2 a (3) Sigm a(g)(+) state and by rotational coupling with the i (3) Pi(g) state. T he observed photofragment anisotropy reveals fine and hyperfine struct ure depolarization. The decay of a (3) Sigma(g)(+) (upsilon=5) levels is dominated by barrier tunneling. The anisotropy parameters is identi fy the symmetry of the continuum to be of mixed Sigma(g) and Pi(g) cha racter, which implies that hydrogen molecules can tunnel through two d ifferent barriers. The determination of the kinetic energy and the ani sotropy parameter of the photofragments have resulted in a number of s pectral reassignments. (C) 1997 American Institute of Physics.