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Figure 3
Representative plot of uncorrected scintillator counts per second versus diode current (points). A Poisson distribution (line) was fitted to these data and the overall agreement shown here implies that the diode current (lower x-axis) was linear with incident flux (proportional to upper x-axis). In this case the incident photon energy was 11 keV, a silica glass target was used as a differential attenuator as described in the text, and the ratio of incident photons diverted to the scintillator over the diode current was 13911 counts s−1 nA−1. The inset highlights a clear deviation from the overall best-fit Poisson model when the SR570 amplifier was using an input impedance of 1 MΩ (blue dots), indicating that the diode became non-linear in this region. This non-linearity was due to the current divider detailed in §2.2 ![]() |