A (M. K.): N₂ makes this gas faster and gives a linear space-time relation. The drift velocity is constant for about two orders of magnitudes of the electrical field. Remember that in drifttubes the field is proportional to 1/r. A more than 100ns longer max. drifttime increases the occupancy of the wire. The non-linear space-time relation reduces the resolution in case of rate effects and changes in high voltage, pressure and temperature.

A (M. K.): Yes, Ar/C0₂ is slower and has a non-linear space-time relation.