HIGH RESOLUTION LASER SPECTROSCOPY IN COLD SUPERSONIC MOLECULAR BEAMS COOLING, REDUCTION OF DOPPLER WIDTH AND APPLICATION

Abstract

The cooling of molecules during the adiabatic expansion of supersonic
seeded molecular beams is reviewed and illustrated by the example of
NO -molecules. The reduction of the Doppler width by collimation of the
beam and the cooling to low rotational temperatures brings a significant
simplification of the complex NO -absorption spectrum and allows its
assignment. The measured rotational temperature is T = 10°K. Some
examples from our work illustrate this promising technique of high resolution
laser spectroscopy in cold beams