A Candidate Substellar Companion to HR 7329
Weinberger, Alycia J.; Schneider, Glenn; Hines, Dean C.; Terrile, Richard J.; Smith, Bradford A.; Zuckerman, B.; Kirkpatrick, J. Davy; Lowrance, Patrick J.; Heap, Sara R.; Schultz, A.; Becklin, E. E.; Plait, Phil; Malmuth, Eliot M.
United States
Abstract
We present the discovery of a candidate substellar companion from a survey of nearby young stars made with the Near-Infrared Camera and Multiobject Spectrometer coronagraph on the Hubble Space Telescope. The H~12 mag object was discovered approximately 4" from the young A0 V star HR 7329. Using follow-up spectroscopy from the Space Telescope Imaging Spectrograph, we derive a spectral type between M7 V and M8 V with an effective temperature of ~2600 K. We estimate that the probability of a chance alignment with a foreground dwarf star of this nature is ~10-8, and therefore we suggest that the object (HR 7329B) is physically associated with HR 7329, with a projected separation of 200 AU. Current brown dwarf cooling models indicate a mass of less than 50 MJup for HR 7329B based on age estimates of <=30 Myr for HR 7329A.