Reciprocity Failure In 1.7μm Cutoff HgCdTe Detectors

摘要

The Detector Characterization Laboratory at NASA/GSFC has investigated the reciprocity failure characteristics of 1.7μm cut-off HgCdTe devices provided by Teledyne Imaging Sensors to the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) project. The reciprocity failure follows a power law behavior over the range of fluxes tested (0.1-10~4 photons/second). The slope of the power law varies among detectors, ranging from ~0.3-1%/dex at 1.0μm, which is much smaller than the ~6%/dex effect observed with the HST NICMOS 2.5μm cut-off detectors. In addition, the reciprocity failure exhibits no wavelength dependence, although only a restricted range of wavelengths (0.85-1.0μm) has been explored to date. Despite its relatively small magnitude, reciprocity failure is nevertheless an important effect in the calibration of WFC3 data, as well as in other applications in which there is a large difference in flux between the photometric standards and the scientific sources of interest.