Ionization and attachment in perfluorobutane

Ionization and attachment coefficients α and η have been obtained in C 4 F 10 under uniform field conditions at pressures in the range 1-20 torr and reduced fields of 80-150 V cm −1 torr −1 . The reduced coefficient α/ p rises from 0·11 at E/p =80 to 0·79 at E/p =150, while η/ p is found to be pressure dependent, at least in the pressure range 1-20 torr. There was no evidence of the presence of detachment at these pressures.