The Companions to B and A Stars Snapshot (C-BASS) Survey: I. Discovery of a Young Brown Dwarf Companion to HIP 17453
Authors:
Marah Brinjikji,
Adam J. Smith,
Jennifer Patience,
Eric Nielsen,
Austin Ware,
Jorge A. Sanchez,
Robert J. De Rosa,
Jasmine Garani,
Emma Softich,
Michael C. Liu,
Bruce Macintosh,
Thomas M. Esposito,
Brendan P. Bowler,
William M. Best,
Sarah Blunt,
Trent Dupuy,
Justin Hom,
Jessica A. Klusmeyer,
Franck Marchis,
Jayke S. Nguyen,
Anne E. Peck,
Mark W. Phillips,
William Roberson,
Jean-Baptiste Ruffio,
William Thompson
, et al. (4 additional authors not shown)
Abstract:
We report the detection of a new brown dwarf companion to HIP 17453 A, a chemically peculiar A0V star located at a distance of 81 pc. HIP 17453 A was observed with high-resolution adaptive optics imaging using the Near-Infrared Camera 2 on the Keck II telescope as part of the Companions to B and A Stars Snapshot (C-BASS) survey over a ten-year baseline, revealing the presence of a companion with p…
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We report the detection of a new brown dwarf companion to HIP 17453 A, a chemically peculiar A0V star located at a distance of 81 pc. HIP 17453 A was observed with high-resolution adaptive optics imaging using the Near-Infrared Camera 2 on the Keck II telescope as part of the Companions to B and A Stars Snapshot (C-BASS) survey over a ten-year baseline, revealing the presence of a companion with proper motion consistent with the primary. We estimate the age of the HIP 17453 system as 280 $\pm$ 125 Myr, and with follow-up intermediate resolution (R~1800) spectroscopic observations with the Gemini Near Infra-Red Spectrograph (GNIRS) on the Gemini-North telescope, we found the spectrum of HIP 17453 B to be consistent with a spectral type of L2 $\pm$ 1. Through interpolation of Sonora Diamondback evolutionary models, we calculate an effective temperature of $1953^{+84}_{-78}$ K and mass of $53^{+10}_{-8}$ $M_{Jup}$ for HIP 17453 B, which corresponds to a mass ratio of $q = 0.024 \pm 0.004$ for the HIP 17453 system. With its intermediate mass and young age, HIP 17453 B joins a small set of benchmark brown dwarf companions around early-type stars that are suitable for follow-up atmospheric and evolutionary studies.
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Submitted 29 June, 2026;
originally announced June 2026.