Instrument Science Report 2003-03:
WFPC2 Cycle 12 Calibration Plan
A. Koekemoer, I. Heyer, G. Brammer, V. Kozhurina-Platais, J. Rhoads, and B. Whitmore
November 10, 2003
The WFPC2 Cycle 12 Calibration Program, extending from October 1, 2003 to September 30, 2004 will continue to monitor the health of WFPC2, using the standard suite of calibrations, as well as some special / Close-Out programs to characterize other aspects of the instrument. One significant recent change in the routine monitors concerns the length of time between decontaminations. Since Cycle 11, this period has been increased from 28 days to 49 days because data from the last few Cycles indicate that the contamination rate has been decreasing. Close-out programs include a characterization of the UV geometric distortion, checks of narrow-band and linear ramp filters, as well as an effort to cross-calibrate WFPC2, ACS and WFC3 photometry. Because there are significantly fewer primary WFPC2 science observations in Cycle 12, the calibration plan has been significantly scaled back, but without sacrificing the quality of data required to calibrate the instrument. For Cycle 12, a total of 25 external orbits will be used, compared to 40 in Cycle 12.
The Complete Paper (PDF 0.1 MB) is available.