First Townsend Ionization Coefficients in Hydrogen and Deuterium

Measurement of the transverse diffusion and Townsend's first ionisation coefficients from the observation of the photon flux produced in a Townsend discharge in molecular hydrogen

“…The present experimental values of Townsend's first ionisation coefficient obtained from the photon distributions are given in figure 6 along with the previous results of Rose (1956) and Barna et al (1964). It can be seen that, in general, good agreement between the present results and those obtained by Barna et a1 has been achieved, although the estimated percentage error in the present results is large, particularly at low E / N .…”