Mobility of He⁺, Ne⁺, Ar⁺, N₂⁺, O₂⁺, and CO₂⁺ in their parent gas

We have used a drift tube with double mass spectrometry to measure the mobility of He⁺, Ne⁺, Ar⁺, N₂⁺, O₂⁺, and CO₂⁺ in their parent gas over a wide range of the density-normalized electric field, $E/N,$ from 70 to 12500×10^-21Vm². In all cases, the $E/N$ ranges have exceeded those hitherto found in the literature, especially those of Ar⁺ in Ar and N₂⁺ in N₂. Our mobility data are in fair to excellent agreement with previous experimental data in the overlap range. Recent calculated data for the mobility of Ar⁺ in Ar show excellent agreement with our data at high $E/N,$ while fair agreement was observed for the calculated data of the systems N₂⁺ in N₂ and O₂⁺ in O₂. Also, the Ar⁺ in Ar mobilities for E/N>10kTd were found in excellent agreement with those derived from the measurement of the mean ion energy in diffuse Townsend discharges (1Td=1townsend=10^-21Vm²). To the best of our knowledge, over some $E/N$ ranges, our data were found to be the first to be reported.