Emission lines from Ne are frequently used as wavelength standards in spectroscopy. Reading around Wikipedia, I found about the Paschen law regarding the voltage required to start a discharge.

My question, do emission line intensities have dependence on the voltage applied and the temperature of the electrodes. Just to clarify, I am not thinking about the band positions but the relative intensities.

  1. About voltage dependence, at present I have no idea.
  2. About temperature : Since the electronic states are involved, and this is an electric discharge, the temperature maybe quite high so as to affect the Boltzmann population significantly.

This question is related to plasma physics, but also to electronic spectroscopy.

  • 1
    $\begingroup$ The intensity of a transition from any given atom is determined by the properties of the atom's electronic states. If you have more atoms to excite and/or excite more of them, the intensity will obviously be greater, but only up to a point. Emission from one excited atom can be absorbed in an unexcited one as the transition frequency is the same. (You can see this with Hg vapour.) However, there is also Doppler and Collisional broadening which will counteract self absorption to a certain extend. $\endgroup$
    – porphyrin
    Apr 16 '20 at 13:01
  • 1
    $\begingroup$ Your question is too broad. It is not a trivial simple relationship. The emission characteristics even depend on the geometry of electrodes. I think the most well studied systems are hollow cathode lamps, where the effect of high voltage and consequently high current have been studied. $\endgroup$
    – M. Farooq
    Apr 16 '20 at 15:38

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