Temporal Evolution of Coronagraphic Dynamic Range and Constraints on Companions to Vega

  title={Temporal Evolution of Coronagraphic Dynamic Range and Constraints on Companions to Vega},
  author={Sasha Hinkley and Ben R. Oppenheimer and R{\'e}mi Soummer and Anand Sivaramakrishnan and L. C. Roberts and Jeffrey R. Kuhn and Russell B. Makidon and Marshall D. Perrin and James P. Lloyd and Kaitlin M. Kratter and Douglas Brenner Columbia University and Department of Theoretical Astrophysics and American Museum of Natural History and Boeing and U. of Hawaii IfA and Stsci and U. California Berkeley and Cornell},
  journal={The Astrophysical Journal},
The major obstacle to the direct detection of companions to nearby stars is the overwhelming brightness of the host star. Current instruments employing the combination of adaptive optics (AO) and coronagraphy can typically detect objects within 2'' of the star that are ~104-105 times fainter. Correlated speckle noise is one of the biggest obstacles limiting such high-contrast imaging. We have obtained a series of 284 8 s, AO-corrected, coronagraphically occulted H-band images of the star Vega… 

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