Eric L. Nielsen, Michael C. Liu, Zahed Wahhaj, Beth A. Biller, Thomas L. Hayward, Alan Boss, Brendan Bowler, Adam Kraus, Evgenya L. Shkolnik, Matthias Tecza, Mark Chun, Fraser Clarke, Laird M. Close, Christ Ftaclas, Markus Hartung, Jared R. Males, I. Neill Reid, Andrew J. Skemer, Silvia H. P. Alencar, Adam Burrows, Elisabethe de Gouveia Dal Pino, Jane Gregorio-Hetem, Marc Kuchner, Niranjan Thatte, Douglas W. Toomey
We report the discovery by the Gemini NICI Planet-Finding Campaign of two
low-mass companions to the young A0V star HD 1160 at projected separations of
81 +/- 5 AU (HD 1160 B) and 533 +/- 25 AU (HD 1160 C). VLT images of the system
taken over a decade for the purpose of using HD 1160 A as a photometric
calibrator confirm that both companions are physically associated. By comparing
the system to members of young moving groups and open clusters with
well-established ages, we estimate an age of 50 (+50,-40) Myr for HD 1160 ABC.
While the UVW motion of the system does not match any known moving group, the
small magnitude of the space velocity is consistent with youth. Near-IR
spectroscopy shows HD 1160 C to be an M3.5 +/- 0.5 star with an estimated mass
of 0.22 (+0.03,-0.04) M_Sun, while NIR photometry of HD 1160 B suggests a brown
dwarf with a mass of 33 (+12,-9) M_Jup. The very small mass ratio (0.014)
between the A and B components of the system is rare for A star binaries, and
would represent a planetary-mass companion were HD 1160 A to be slightly less
massive then the Sun.
View original:
http://arxiv.org/abs/1202.2854
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