1202.4964 (John P. Wisniewski et al.)

Very Low-Mass Stellar and Substellar Companions to Solar-Like Stars from MARVELS I: A Low Mass Ratio Stellar Companion to TYC 4110-01037-1 in a 79-day Orbit    [PDF]

John P. Wisniewski, Jian Ge, Justin R. Crepp, Nathan De Lee, Jason Eastman, Massimiliano Esposito, Scott W. Fleming, B. Scott Gaudi, Luan Ghezzi, Jonay I. Gonzalez Hernandez, Brian L. Lee, Keivan G. Stassun, Eric Agol, Carlos Allende Prieto, Rory Barnes, Dmitry Bizyaev, Phillip Cargile, Liang Chang, Luiz N. Da Costa, G. F. Porto De Mello, Bruno Femenia, Leticia D. Ferreira, Bruce Gary, Leslie Hebb, Jon Holtzman, Jian Liu, Bo Ma, Claude E. Mack III, Suvrath Mahadevan, Marcio A. G. Maia, Duy Cuong Nguyen, Ricardo L. C. Ogando, Daniel J. Oravetz, Martin Paegert, Kaike Pan, Joshua Pepper, Rafael Rebolo, Basilio Santiago, Donald P. Schneider, Alaina C Shelden, Audrey Simmons, Benjamin M. Tofflemire, Xiaoke Wan, Ji Wang, Bo Zhao

TYC 4110-01037-1 has a low-mass stellar companion, whose small mass ratio and short orbital period are atypical amongst solar-like (Teff ~< 6000 K) binary systems. Our analysis of TYC 4110-01037-1 reveals it to be a moderately aged (~<5 Gyr) solar-like star having a mass of 1.07 +/- 0.08 MSun and radius of 0.99 +/- 0.18 RSun. We analyze 32 radial velocity measurements from the SDSS-III MARVELS survey as well as 6 supporting radial velocity measurements from the SARG spectrograph on the 3.6m TNG telescope obtained over a period of ~2 years. The best Keplerian orbital fit parameters were found to have a period of 78.994 +/- 0.012 days, an eccentricity of 0.1095 +/- 0.0023, and a semi-amplitude of 4199 +/- 11 m/s. We determine the minimum companion mass (if sin i = 1) to be 97.7 +/- 5.8 MJup. The system's companion to host star mass ratio, >0.087 +/- 0.003, places it at the lowest end of observed values for short period stellar companions to solar-like (Teff ~< 6000 K) stars. One possible way to create such a system would be if a triple-component stellar multiple broke up into a short period, low q binary during the cluster dispersal phase of its lifetime. A candidate tertiary body has been identified in the system via single-epoch, high contrast imagery. If this object is confirmed to be co-moving, we estimate it would be a dM4 star. We present these results in the context of our larger-scale effort to constrain the statistics of low mass stellar and brown dwarf companions to FGK-type stars via the MARVELS survey.

View original: http://arxiv.org/abs/1202.4964