Generation of Radiation on Forbidden Transitions in the Laboratory Acoustic Plasma

Experimentally, under laboratory conditions in the nitrogen acoustic plasma in the region of the forbidden lines at 654.81 and 658.36 nm, a spectral emission line of high intensity was obtained (up to 17 stronger than the neighboring lines of the first positive system of nitrogen). The results were obtained both in pure low-pressure nitrogen acoustic plasma (several hundreds of Pa) and various mixtures containing nitrogen, including the CO₂ : N₂ : He = 1 : 1 : 8 mixture. The results obtained are explained by the acoustic plasma state of the discharge and an analog of Rahman scattering, which remove some of the quantum mechanical prohibitions. The possible influence of the Coriolis force is also considered.