THE DRIFT VELOCITY AND LONGITUDINAL DIFFUSION-COEFFICIENT OF ELECTRONS IN NITROGEN AND CARBON-DIOXIDE FROM 20 TO 1000 TD

The distribution of arrival time spectra (ATS) of electrons in nitroge n (N-2) and carbon dioxide (CO2) has been measured over the range of E /N from 20 to 1000 Td (1 Td=10(-17) V cm(2)) at room temperature by a double-shutter drift tube. The drift velocity (W-m) of electrons in N- 2 and CO2 was evaluated from these distributions by the ATS method. Mo reover, the ratio (D-L/mu) of the longitudinal diffusion coefficient ( D-L) to the electron mobility (mu) was measured. The values of W-m and D-L/mu in N-2 and CO2 were in good agreement with experimental and th eoretical values obtained by previous investigators except for a few o f the earlier studies.