  Non-classical electron diffusion in crossed-field, low-temperature plasmas is
measured experimentally. Laser-induced fluorescence and Thomson scattering are
used to determine the inverse Hall parameter, a metric for cross-field
transport, in a Hall ion source. The measured diffusion is found to depart from
fluid model results at the peak electric field, remaining constant instead of
exhibiting a sharp transport barrier. The implications of this result are
discussed in terms of the current understanding of non-classical diffusion in
low-temperature plasmas.
