The drift velocity vector of electron swarms in crossed electric and magnetic fields

We calculated the drift velocity vector W Of electron swarms in crossed electric and magnetic fields using a Monte Carlo method. Values of W in F-2, CF4 and constant-collision-frequency (CCF) model gases at various values of the reduced electric and magnetic fields, E/N and B/N (N is the gas molecule number density), were illustrated as vector loci in velocity space. Under a CCF condition, W draws right semicircular loci with varying B and N at a constant E when the number of electrons is conservative. These semicircular loci can be a reference to characterize the W behaviour in real gases. We presented an analytical derivation of W in the CCF condition, extending its expression to that in the presence of ionization and attachment. Features of thr vector loci in F-2 and CF4 were discussed.