  This paper presents the results of a study of the response of a test CMOS
sensor with a radiation tolerant pixel cell design to 80 keV and 100 keV
electrons. The point spread function is measured to be (13.0+/- 1.7) microns at
100 keV and (12.1 +/- 1.6) microns at 80 keV, for 20 micron pixels. Results
agree well with values predicted by a Geant-4 and dedicated charge collection
simulation.
