Thermal-electron attachment to SF₆at room temperature and 500K

The validity of a previous measurement of the attachment rate of thermal electrons to SF 6 by Crompton and Haddad (1983) using an electron density sampling technique has been examined with specific reference to the possible effects on non-Boltzmann vibrational populations of the carrier gas and of the decay of high-order diffusion modes. Measurements made with several atomic and molecular buffer gases support the earlier results at room temperature. A comparison of attachment rates measured with this technique at 294 and 500K does not support the temperature dependence obtained by Smith et al. (1984) using the flowing afterflow Langmuir probe technique.