Maser Radiation Produced by Gas Discharges

Microwave radiation produced by sliding (spark channel) discharges in small gaps under the action of a high (
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MV/cm) electric field over dielectric (plexiglass) substrates is studied in high pressure of the hydrogen/argon mixtures. When the resonant cavity is tuned close to 1.4 GHz, it is observed that the frequency of the radiation in the resonant cavity is 1.420 GHz. This frequency is related to the intrinsic property of the hydrogen atoms and corresponds to the radiation produced by the atomic hydrogen maser. The objective of this paper is to gain information on how the changes in the resonant cavity affect the frequency of radiation of an atomic hydrogen maser.