  For the successful design and operation of gas based particle detectors, one
needs a good understanding of the drift properties of the deployed gas. This
includes the drift velocity of electrons, their diffusion and the gas
amplification in different electric and magnetic fields. This work presents
simulations and precision measurements of the drift velocity vd in low electric
fields (< 400 V/cm) for argon-based gas mixtures with up to two additives. The
additives used are CH4, CO2, CF4, iC4H10 and H2.
