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A Candidate Substellar Companion to HR 7329

P. J. Lowrance·G. Schneider·J. D. Kirkpatrick·E. E. Becklin·A. J. Weinberger·B. Zuckerman·P. Plait·E. Malmuth·S. Heap·A. Schultz·B. A. Smith·R. J. Terrile·D. C. Hines
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Abstract

We present the discovery of a candidate substellar companion from a survey of nearby, young stars with the NICMOS coronagraph on the Hubble Space Telescope. The H ~ 12 mag object was discovered approximately 4" from the young A0V star HR 7329. Using follow-up spectroscopy from STIS, we derive a spectral type between M7V and M8V 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 suggest 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 Jupiter masses for HR 7329B based on age estimates of < 30 Myr for HR7329A.

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P. J. Lowrance, G. Schneider, J. D. Kirkpatrick, E. E. Becklin, A. J. Weinberger, B. Zuckerman, P. Plait, E. Malmuth, S. Heap, A. Schultz, B. A. Smith, R. J. Terrile, D. C. Hines. 2000-05-02. A Candidate Substellar Companion to HR 7329. https://doi.org/10.1086/309437

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