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DONUTS: A science frame autoguiding algorithm with sub-pixel precision, capable of guiding on defocused stars

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 Added by James McCormac Ph.D
 Publication date 2013
  fields Physics
and research's language is English
 Authors J. McCormac




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We present the DONUTS autoguiding algorithm, designed to fix stellar positions at the sub-pixel level for high-cadence time-series photometry, which is also capable of autoguiding on defocused stars. DONUTS was designed to calculate guide corrections from a series of science images and re-centre telescope pointing between each exposure. The algorithm has the unique ability of calculating guide corrections from under-sampled to heavily defocused point spread functions. We present the case for why such an algorithm is important for high precision photometry and give our results from off and on-sky testing. We discuss the limitations of DONUTS and the facilities where it soon will be deployed.

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