Abstract
Direct experimental measurements of electron diffusion coefficients in helium have been carried out at 300°K in the range of V ( V ) by an improved electron-density sampling method. Absolute errors less than ± 0.5% are claimed in the range V and less than 1.5% in the range V .
The obtained values of are in agreement with those of Crompton, Elford, and Jory in the range of V studied by these authors. Also measurements of (where is Townsend's first coefficient and the drift velocity) have been performed in the range V (corresponding to V ). Values of with an accuracy evaluated at ± 10% are obtained by dividing by the values found in the literature. These values are to be compared with those of the literature, which are dispersed by a factor of 3 in the above range.
- Received 11 September 1968
DOI:https://doi.org/10.1103/PhysRev.179.186
©1969 American Physical Society