Wide field camera 3 ground testing and calibration

Wide Field Camera 3 (WFC3), a panchromatic imager developed for the Hubble Space Telescope (HST), is fully integrated with its flight detectors and has undergone several rounds of ground testing and calibration at Goddard Space Flight Center (GSFC). The testing processes are highly automated, with WFC3 and the optical stimulus, which is used to provide external targets and illumination, being commanded by coordinated computer scripts. All test data are captured and stored in the long-term Hubble Data Archive. A full suite of instrument characterization and calibration tests has been performed, including the measurement of key detector properties such as dark current, read noise, flat field response, gain, linearity, and persistence, as well as instrument-level properties like total system throughput, imaging quality and encircled energy, grism dispersions, IR thermal background, and image stability. Nearly all instrument characteristics have been shown to meet or exceed expectations and requirements.