  Experimental studies of electron mobilities in Neon as a function of the gas
density have persistently shown mobilities up to an order of magnitude smaller
than expected and predicted. A previously ignored mechanism (gas
in--homogeneity which is negligible in the thermal mobilities for He and other
gases) is found to reproduce the observed Neon mobilities accurately and simply
at five temperatures with just one variable parameter. Recognizing that a gas
is not a homogeneous medium, a variation in local density combined with the
quantum multi--scattering theory, shifts the energy and cross section -- which
in turn changes the collision probability and finally the mobilities. A lower
density where a momentum transfer interaction occurs moves the mobility
strongly in the same direction as the anomalous experiments. By going backwards
from the observed mobilities, the collision frequency at each temperature and
density is made to reproduce the experimental data by looking for the local (as
opposed to average) density at which the (rare) momentum transfer interactions
occur. These density deviations give a picture of the size and behavior of the
wave packets for electron motion which looks very much like the often discussed
wave function collapse.
