A SIMPLE METHOD FOR MEASUREMENT OF THE FULL 3-DIMENSIONAL VELOCITY DISTRIBUTION OF PHOTOFRAGMENTS AND REACTION-PRODUCTS

We describe and demonstrate a simple and general laser spectroscopic a pproach for quantum-state-resolved measurement of all three components of the recoil velocity of the products of photodissociation or photoi nduced chemical reactions. The method relies on pulsed-laser determina tion of the time-of-flight distribution of the products. We call this method POSTS, for position sensitive translational spectroscopy. POSTS requires only a single probe laser, which does not have to have a nar row frequency bandwidth. The method is applicable to all atomic and mo lecular species and will work with most laser detection schemes.