The Spectra Emitted by the High Voltage Arc in Nitrogen, Hydrogen, Nitrogen-Hydrogen Mixtures and Ammonia

The spectra emitted by the high voltage arc in nitrogen, hydrogen, hydrogen-nitrogen mixtures and ammonia have been studied. The appearance of the N 2 Second Positive bands at various nitrogen gas pressures is discussed and the divergence of rotational and vibrational temperatures is noted. Traces of oxygen greatly reduce the strength of the N + bands emitted by the arc in nitrogen. In N 2 -H 2 mixtures the NH 3360 Å band is found to be emitted strongly only when hydrogen is present at a very low partial pressure. An attempt is made to explain the various observations.