A pure-rotational collisionally pumped OH laser

Abstract
Laser oscillation is reported on certain pure‐rotational transitions in the ground electronic state of the hydroxyl ion, v=0 and v=1. the active medium has been prepared by the O(1D)+H2 reaction in a large excess of rare gas. The transitions on which oscillation occurs have upper states which are energetically resonant with one, or even two, vibrational quanta. The pumping mechanism is assigned as a VR transfer with ΔJ the order of 12.