ACS Polarization Calibration - Data, Throughput, and Multidrizzle Weighting

A subset of the polarized images from calibration proposals 9586, 9661, and 10055 were analyzed to help determine the polarization calibration accuracy level of the ACS camera. The polarization values found here are shown to be accurate to better than 1%. The absolute throughput values found while performing these calibration exercises did not match those currently listed in the synphot/ETC database, and we recommend these be updated in the system. Lastly, we examine the differences between two weighting schemes used in the multidrizzle software. The exposure time weighting, EXP, is found to more accurately preserve the flux levels than the error weighting scheme, ERR, for datasets with a small number of images being combined.