Direct imaging of a massive dust cloud around R Coronae Borealis

@article{Jeffers2012DirectIO,
  title={Direct imaging of a massive dust cloud around R Coronae Borealis},
  author={S. V. Jeffers and Michiel Min and L. B. F. M. Waters and H{\'e}ctor C{\'a}novas and Michiel Rodenhuis and Maria de Juan Ovelar and Ana L. Chies-Santos and Christoph U. Keller},
  journal={Astronomy and Astrophysics},
  year={2012},
  volume={539}
}
We present recent polarimetric images of the highly variable star R CrB using ExPo and archival WFPC2 images from the HST. We observed R CrB during its current dramatic minimum where it decreased more than 9 mag due to the formation of an obscuring dust cloud. Since the dust cloud is only in the line-of-sight, it mimics a coronograph allowing the imaging of the star’s circumstellar environment. Our polarimetric observations surprisingly show another scattering dust cloud at approximately 1.3… 

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