Previous | Session 125 | Next | Author Index | Block Schedule
R.J. Hill (SSAI/GSFC), A. Waczynski, S.D. Johnson (GST/GSFC), P. Marshall (NASA Consultant), C. Marshall (GSFC), R. Foltz (Sigma Space/GSFC), R.A. Kimble (GSFC)
The near-IR channel of Wide Field Camera 3, an instrument being developed for installation onto the Hubble Space Telescope, employs a Rockwell Scientific Company 1K x 1K HgCdTe detector array hybridized to a Hawaii-1R multiplexer. Radiation testing of test detectors showed that the WFC3 detectors do not exhibit a post-SAA glow of the sort seen in the NICMOS detectors. However, an anomalously high background was observed during the irradiation in the proton beam. This background goes away promptly when the beam is turned off. Subsequent testing and analysis revealed that the background arises due to emission of photons from within the CdZnTe detector substrate at the blue transmission edge of the substrate material. Further testing of devices with the substrate removed show no excess background signal. These results lead to a recommendation that the CdZnTe substrate material should be removed for space applications which require the ability to detect faint objects.
Previous | Session 125 | Next
Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.