Instrument Science Report WFPC2 2010-03:
WFPC2 CTE for Extended Sources: I. Photometric Correction
N. A. Grogin, R. Lucas, D. Golimowski, and J. Biretta
August 13, 2010
We measure the effects of charge transfer efficiency (CTE) losses on resolved sources in Wide Field and Planetary Camera 2 (WFPC2) images from 1995 to 2008. We compare medium and long exposures of the Hubble Deep Field – North taken with the F606W filter at several epochs against a “truth” mosaic of the field taken with the Advanced Camera for Surveys early in that instrument’s operation. We adopt the Dolphin (2009) functional form for the CTE photometric correction and determine the optimal coefficients for extended sources on the Wide Field (WF) detectors as a function of observation date, pre-corrected source flux, background flux, and source position on the detector.
The Complete Paper (PDF 1.2 MB) is available.