Lifetime of the 3Σu+ State of Nitrogen

Abstract
A new method is proposed for the measurement of the ``free space'' lifetimes of particles in metastable states. An average lifetime of 2.3×10−4 second is obtained for nitrogen molecules in the A 3Σu+ state. The method also gives the collision diameter for collisions between metastable and normal N2 molecules as 3.8A. Measurements of the appearance potential for molecules in the A state are presented.