Direct Imaging Discovery of a Young Brown Dwarf Companion to an A2V Star
Kevin Wagner, D\'aniel Apai, Markus Kasper, Melissa McClure, Massimo, Robberto, Thayne Currie

TL;DR
This paper reports the direct imaging discovery of a young brown dwarf companion to an A2V star, providing insights into its properties, orbit, and formation scenario, and demonstrating the capability to detect low-mass companions near habitable zones.
Contribution
First direct imaging detection of a young brown dwarf companion at small separation around an A-type star, with detailed spectral, orbital, and formation analysis.
Findings
Companion spectral type M6-L2, T_eff ~2000-2600 K
Mass estimated at 20-30 Jupiter masses
Orbital semi-major axis ~15-45 au, face-on inclination
Abstract
We present the discovery and spectroscopy of HIP 75056Ab, a companion directly imaged at a very small separation of 0.125 arcsec to an A2V star in the Scorpius-Centaurus OB2 association. Our observations utilized VLT/SPHERE between 20152019, enabling low-resolution spectroscopy (0.951.65 ), dual-band imaging (2.12.25 ), and relative astrometry over a four-year baseline. HIP 75056Ab is consistent with spectral types in the range of M6L2 and 20002600 K. A comparison of the companion's brightness to evolutionary tracks suggests a mass of 2030 M. The astrometric measurements are consistent with an orbital semi-major axis of 1545 au and an inclination close to face-on (i35). In this range of mass and orbital separation, HIP 75056Ab is likely at the low-mass end of the distribution of companions formed via…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
