Jiang, P.; Ge, Jian; Cargile, Phillip; Crepp, Justin R.; De Lee, Nathan; Porto de Mello, Gustavo F.; Esposito, M.; Ferreira, Letícia D.; Femenía, B.; Fleming, Scott W.; Gaudi, B. Scott; Ghezzi, Luan; González Hernández, J. I.; Hebb, Leslie; Lee, Brian L.; Ma, Bo; Stassun, Keivan G.; Wang, Ji; Wisniewski, John P.; Agol, Eric; Bizyaev, Dmitry; Brewington, Howard; Chang, Liang; Nicolaci da Costa, Luiz; Eastman, Jason D.; Ebelke, Garrett; Gary, Bruce; Kane, Stephen R.; Li, Rui; Liu, Jian; Mahadevan, Suvrath; Maia, Marcio A. G.; Malanushenko, Viktor; Malanushenko, Elena; Muna, Demitri; Nguyen, Duy Cuong; Ogando, Ricardo L. C.; Oravetz, Audrey; Oravetz, Daniel; Pan, Kaike; Pepper, Joshua; Paegert, Martin; Allende-Prieto, C.; Rebolo, R.; Santiago, Basilio X.; Schneider, Donald P.; Shelden Bradley, Alaina C.; Sivarani, Thirupathi; Snedden, Stephanie; van Eyken, J. C.; Wan, Xiaoke; Weaver, Benjamin A.; Zhao, Bo
Bibliographical reference
The Astronomical Journal, Volume 146, Issue 3, article id. 65, 11 pp. (2013).
Description
We report the discovery of a candidate brown dwarf (BD) or a very low
mass stellar companion (MARVELS-5b) to the star HIP 67526 from the
Multi-object Apache point observatory Radial Velocity Exoplanet
Large-area Survey (MARVELS). The radial velocity curve for this object
contains 31 epochs spread over 2.5 yr. Our Keplerian fit, using a Markov
Chain Monte Carlo approach, reveals that the companion has an orbital
period of 90.2695^{+0.0188}_{-0.0187} days, an eccentricity of 0.4375
± 0.0040, and a semi-amplitude of 2948.14^{+16.65}_{-16.55} m
s–1. Using additional high-resolution spectroscopy, we
find the host star has an effective temperature T eff = 6004
± 34 K, a surface gravity log g (cgs) =4.55 ± 0.17, and a
metallicity [Fe/H] =+0.04 ± 0.06. The stellar mass and radius
determined through the empirical relationship of Torres et al. yields
1.10 ± 0.09 M ⊙ and 0.92 ± 0.19 R
⊙. The minimum mass of MARVELS-5b is 65.0 ± 2.9M
Jup, indicating that it is likely to be either a BD or a very
low mass star, thus occupying a relatively sparsely populated region of
the mass function of companions to solar-type stars. The distance to
this system is 101 ± 10 pc from the astrometric measurements of
Hipparcos. No stellar tertiary is detected in the high-contrast images
taken by either FastCam lucky imaging or Keck adaptive optics imaging,
ruling out any star with mass greater than 0.2 M ⊙ at a
separation larger than 40 AU.
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