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+, N-2(+), O-2(+), and CO2+ in their parent gas over a wide range of the density-normalized electric field, E/N, from 70 to 12 500X 10(-21) V m(2). In all cases, the E/N ranges have exceeded those hitherto found in the literature, especially those of Ar+ in Ar and N-2(+) in N-2. 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 N-2(+) in N-2 and O-2(+) in O-2. Also, the Ar+ in Ar mobilities for E/N> 10 kTd were found in excellent agreement with those derived from the measurement of the mean ion energy in diffuse Townsend discharges (1 Td=1 townsend= 10(-21) V m(2)). To the best of our knowledge, over some E/N ranges, our data were found to be the first to be reported.