We present a new method of analyzing measurements of mesospheric
dust made with DUSTY rocket-borne Faraday cup probes. It can yield the
variation in fundamental dust parameters through a mesospheric cloud with an
altitude resolution down to 10 cm or less if plasma probes give the plasma
density variations with similar height resolution. A DUSTY probe was the
first probe that unambiguously detected charged dust and aerosol particles in
the Earth's mesosphere. DUSTY excluded the ambient plasma by various biased
grids, which however allowed dust particles with radii above a few nanometers
to enter, and it measured the flux of charged dust particles. The flux
measurements directly yielded the total ambient dust charge density.
We extend the analysis of DUSTY data by using the impact currents on its main
grid and the bottom plate as before, together with a dust charging model and
a secondary charge production model, to allow the determination of
fundamental parameters, such as dust radius, charge number, and total dust
density. We demonstrate the utility of the new analysis technique by
considering observations made with the DUSTY probes during the MAXIDUSTY
rocket campaign in June–July 2016 and comparing the results with those of
other instruments (lidar and photometer) also used in the campaign. In the
present version we have used monodisperse dust size distributions.</p