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arXiv · 2004.05180

The Parallax of VHS J1256-1257 from CFHT and Pan-STARRS 1

Trent J. Dupuy·Michael C. Liu·Eugene A. Magnier·William M. J. Best·Isabelle Baraffe·Gilles Chabrier·Thierry Forveille·Stanimir A. Metchev·Pascal Tremblin
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Abstract

We present new parallax measurements from the CFHT Infrared Parallax Program and the Pan-STARRS 3$\pi$ Steradian Survey for the young ($\approx150-300$ Myr) triple system VHS J125601.92$-$125723.9. This system is composed of a nearly equal-flux binary ("AB") and a wide, possibly planetary-mass companion ("b"). The system's published parallactic distance ($12.7\pm1.0$ pc) implies absolute magnitudes unusually faint compared to known young objects and is in tension with the spectrophotometric distance for the central binary ($17.2\pm2.6$ pc). Our CFHT and Pan-STARRS parallaxes are consistent, and the more precise CFHT result places VHS J1256-1257 at $22.2^{+1.1}_{-1.2}$ pc. Our new distance results in higher values for the companion's mass ($19\pm5$ M$_{\rm Jup}$) and temperature ($1240\pm50$ K), and also brings the absolute magnitudes of all three components into better agreement with known young objects.

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Trent J. Dupuy, Michael C. Liu, Eugene A. Magnier, William M. J. Best, Isabelle Baraffe, Gilles Chabrier, Thierry Forveille, Stanimir A. Metchev, Pascal Tremblin. 2020-04-10. The Parallax of VHS J1256-1257 from CFHT and Pan-STARRS 1. https://arxiv.org/abs/2004.05180

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