Calibration of a multiple microchannel plate detectors system by α-induced secondary electrons

α particles emitted from an Am241 radioactive source at energies of 5.4 MeV generate bursts of about ten electrons when passing through an aluminized Mylar foil. Besides the typical surface barrier electrons, the energy spectra of the secondary electrons clearly reveal two additional peaks. One at 66 eV is ascribed to aluminum LVV Auger electrons and another at 10.5 eV is attributed to the decay of aluminum volume plasmons. The well-resolved angular and energy distributions of these secondary electrons are used to calibrate the relative detection efficiencies of a large set of individual detectors of a complex multicoincidence system.