STIS/CCD Time Series Photometry with Saturated Data
نویسنده
چکیده
STIS/CCD data were acquired in a time series mode on α Cen A & B to test limitations to ultra high Signal to Noise (S/N) capabilities. In order to reach a Poisson limited noise level of nearly 40,000 on α Cen A the data were acquired in a spectral mode to spread the image over a full row of pixels, and with an exposure time that led to strong over-saturation. Each 10s exposure resulted in detection of ~ efor α Cen A and ~ efor α Cen B, with the latter spectrum just at saturation in some spectral regions. I discuss the data characteristics in detail and present time series results under a reasonable analysis approach. Simple interpretations from this one orbit of calibration data are hindered as a result of unusually large instrument drifts. A S/N greater than 9400 per exposure was reached for α Cen A, and greater than 6800 for α Cen B.
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