Measurements of electron drift velocities and positive ion mobilities for gases containing CF₄ II

Measurements of electron drift velocities and positive ion mobilities for gases containing CF₄ have been made. Our previous paper described the results on electron drift velocities for gas mixtures containing CF₄ and hydrocarbon, and ion mobility results for gas mixtures of CF₄ + hydrocarbon, Ar + C₂H₆ and Ar + C₃H₈. The present paper is the second and final paper of the series. It describes the results on electron drift velocities for the gas mixtures; Ar + CF₄ + hydrocarbon, where hydrocarbon is CH₄ or C₂H₆ or C₃H₈ or iso-C₄H₁₀. The fraction of each gas component was changed systematically for each set of gas mixtures, and the electron drift velocity was measured as a function of the applied drift field between 0.2 and 2.5 kV/cm. Indications were found for relatively large electron drift velocities, even for low electric fields, with better saturation properties than was the case for the gas mixtures of CF₄ + hydrocarbon previously measured. Positive ion mobility was measured for several kinds of gas mixtures; Ar + hydrocarbon, CF₄ + hydrocarbon and Ar + CF₄ + hydrocarbon. Since ion currents and their arrival times were actually measured, the word "positive ion" does not necessarily mean a specific kind of ions but rather a group of ion clusters. The positive ion mobilities were deduced from this measurement under the assumption that Blanc's law was valid. A consistent picture was obtained within this approximation.