HST/WFC3: UVIS Detector Chip Dependent Photometry, Stability, High Precision Photometry with Spatial Scanning
Abstract
The Wide Field Camera 3 (WFC3) instrument was installed on HST in 2009. The two UVIS CCD chips were constructed on different wafers, making them independent detectors. Motivated by the difference in the quantum efficiency, white dwarf observations were taken in all 42 filters at different positions across each chip to characterize chip-dependent structure of the PSF. We discuss the computation of the average sensitivity ratio per chip for all UVIS filters, which are important for deriving the new chip-dependent zeropoints. We also present the new chip dependent zeropoints and encircled energy curves.
- Publication:
-
IAU General Assembly
- Pub Date:
- August 2015
- Bibcode:
- 2015IAUGA..2258153B