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Confirmation of the planet around HD 95086 by direct imaging

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 نشر من قبل Julien Rameau
 تاريخ النشر 2013
  مجال البحث فيزياء
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VLT/NaCo angular differential imaging at L (3.8 microns) revealed a probable giant planet comoving with the young and early-type HD 95086 also known to harbor an extended debris disk. The discovery was based on the proper motion analysis of two datasets spanning 15 months. However, the second dataset suffered from bad atmospheric conditions, which limited the significance of the redetection at the 3 sigma level. In this Letter, we report new VLT/NaCo observations of HD 95086 obtained on 2013 June 26-27 at L to recover the planet candidate. We unambiguously redetect the companion HD 95086 b with multiple independent pipelines at a signal-to-noise ratio greater than or equal to 5. Combined with previously reported measurements, our astrometry decisively shows that the planet is comoving with HD 95086 and inconsistent with a background object. With a revised mass of 5 pm 2 Jupiter masses, estimated from its L photometry and hot-start models at 17 pm 4 Myr, HD 95086 b becomes a new benchmark for further physical and orbital characterization of young giant planets.

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