Quenching of Na(3p2P) atoms by N2 and CO molecules at low temperatures

Quenching cross sections of Na(3 2P) by N2 and CO molecules at temperatures below 400 K have been measured by studying the dependence of the 3 2P lifetime on gas pressure. An original pulsed laser configuration has been employed to excite Na atoms. Lifetimes have been measured by the delayed coincidence method. From comparison of the present result with previous ones a linear dependence of quenching cross section on reciprocal mean kinetic energy can be inferred.