Improved Contrast in Images of Exoplanets Using Direct Signal-to-noise Ratio Optimization

  title={Improved Contrast in Images of Exoplanets Using Direct Signal-to-noise Ratio Optimization},
  author={William Thompson and Christian Marois},
  journal={The Astronomical Journal},
Direct imaging of exoplanets is usually limited by quasi-static speckles. These uncorrected aberrations in a star’s point-spread function (PSF) obscure faint companions and limit the sensitivity of high-contrast imaging instruments. Most current approaches to processing differential imaging sequences like angular differential imaging and spectral differential imaging produce a self-calibrating data set that is combined using a linear least-squares solution to minimize the noise. Due to temporal… 


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