STScI - Space Telescope Science Institute, Baltimore, MD
United States

Miscellaneous Information

Miscellaneous Information

Abstract Reference: 31247
Identifier: P8.2
Presentation: Poster presentation
Key Theme: 8 Other

SBC Point Spread Functions and Encircled Energy Curves

Avila Roberto J., Chiaberge Marco

We present updated point spread functions (PSF) for the Advanced Camera for Surveys Solar Blind Channel (ACS/SBC).  The currently available PSF models (via Tiny Tim) were derived during ground testing and were never updated once the instrument was put in orbit. As part of a campaign to improve the instrument calibrations, we observed a white dwarf using three filters (F125LP, F140LP, F150LP) and derived new PSFs. The new PSFs contain more flux in the wings than the Tiny Tim models. We also generated new encircled energy curves, of which only two filters were available. With these new measurements in hand, a more accurate absolute flux calibration can be determined.