9223053 Doak Professor Doak will develop a novel method to measure atomic integral scattering cross sections in collisions between two atomic beams down to collision velocities as low as 5 meters per second. A diffracting, single-crystal surface will be employed in the roll of a "beam-splitter" to combine and exactly co-align the two atomic beams. Integral cross section measurements at ultra-low collision energies will open an entirely new window on atom-atom interaction, supplying accurate information on orbiting resonances and resonances associated with marginally bound dimers. ***
