SCExAO/CHARIS Direct Imaging of A Low-mass Companion At A Saturn-like Separation from an Accelerating Young A7 Star

  title={SCExAO/CHARIS Direct Imaging of A Low-mass Companion At A Saturn-like Separation from an Accelerating Young A7 Star},
  author={Jeffrey K. Chilcote and Taylor L. Tobin and Thayne M. Currie and Timothy D. Brandt and Tyler D. Groff and Masayuki Kuzuhara and Olivier Guyon and Julien Lozi and Nemanja Jovanovic and Ananya Sahoo and V. Deo and Eiji Akiyama and Markus Janson and Jill Knapp and Jungmi Kwon and Michael W. McElwain and Jun Nishikawa and Kevin R. Wagner and Krzysztof G. Hełminiak and Motohide Tamura},
  journal={The Astronomical Journal},
  • J. Chilcote, T. Tobin, +17 authors Motohide Tamura
  • Published 24 September 2021
  • Physics
  • The Astronomical Journal
We present the SCExAO direct imaging discovery and characterization of a low-mass companion to the nearby young A7IV star, HD 91312. SCExAO/CHARIS JHK (1.1–2.4 μm) spectra and SCExAO/HiCIAO H-band imaging identify the companion over a two year baseline in a highly inclined orbit with a maximum projected separation of 8 au. The companion, HD 91312 B, induces an 8.8σ astrometric acceleration on the star as seen with the Gaia & Hipparcos satellites and a long-term radial-velocity trend as… Expand


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