A. GILKISON, J. CLARK, C. R. VITERI AND E. R. GRANT, Purdue University, Department of Chemistry, West Lafayette, IN USA..
The A 1 state of BH is characterized by its barrier to dissociation. We have observed new structure in the v=3, J=4-7 region near the top of the barrier by means of constant energy scans over intermediate states in double resonant transitions locked on single B 1 - X 1 transitions. Linewidths provide new information on the barrier height and tunneling lifetimes.