Laser Double Resonance Studies of Rotational Relaxation in a Supersonic Molecular Beam

Abstract

The technique of the supersonic molecular beam and that of the infrered laser Stark spectroscopy are combined in the present work and applied to the study of the elementary processes of collision-induced transitions among vibration-rotation energy levels of molecules. The molecules are prepared in a spectroscopically and also kinematically “pure” state. The velocity distribution in the molecular beam is quite monochromatic, and the molecules are populated mostly in several low-lying energy levels. Various controls to the molecular system can be introduced by using the external fields and the laser radiations. The detection sensitivity is quite high because of high intensity of molecular flux. These allow us to obtain detailed and precise knowledge on molecular dynamics. Three examples of the recent investigations are shown below.