Lucky imaging and speckle discrimination for the detection of faint companions with adaptive optics

  title={Lucky imaging and speckle discrimination for the detection of faint companions with adaptive optics},
  author={Szymon Gladysz and Julian Christou and Nicholas M. Law and Richard Dekany and Michael Redfern and Craig Mackay},
  booktitle={Astronomical Telescopes + Instrumentation},
We have analyzed the application of frame selection ("lucky imaging") to adaptive optics (AO), short-exposure observations of faint companions. We have used the instantaneous Strehl ratio as an image quality metric. The probability density function (PDF) of this quantity can be used to determine the outcome of frame selection in terms of optimizing the Strehl ratio and the peak-signal-to-noise-ratio of the shift-and-add image. In the presence of static speckles, frame selection can lead to both… 

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