Nonlinearity and polarization effects in silicon trap detectors

The study reported here was carried out as part of an international comparison of cryogenic radiometers, using silicon trap detectors as transfer instruments. Nonlinearity measurements are part of a more general characterization process of these detectors, including, among other parameters, spatial uniformity, temperature coefficient, sensitivity to beam polarization, and stability. When calibrated against cryogenic radiometers, the uncertainty in their calibration is of the order of 1 part in 10(4). The accuracy in the nonlinearity measurements should therefore be better than this value.