Self-Reversal of the Hα Hydrogen Line in the High Pressure Spark Discharge*

Abstract

With increasing gas pressure and spark energy, the Balmer lines in the hydrogen spectrum (with the exception of Hα) become so wide and overlapping that they form a continuous spectrum, as is well known. Only Hα remains relatively sharp and separated even with the highest energies obtained so far.By increasing the energy density in the spark channel substantially beyond the present limits, Hα also widens considerably and finally shows reversal in its center. The spectral range of the reversal widens with increasing energy and gas pressure. The phenomenon is discussed.