A low-mass stellar companion of the planet host star HD 75289

Author(s)

M. Mugrauer, R. Neuhäuser, T. Mazeh, J. Alves, E. Guenther

Abstract

We report on the detection of a new low-mass stellar companion of HD

75289, a G0V star that harbors one known radial-velocity planet (Udry et

al. \cite{Udry00}, A&A, 356, 590). Comparing an image from 2MASS

with an image we obtained with SofI at the ESO 3.58 m NTT three years

later, we detected a co-moving companion located 21.465±0.023

arcsec (621±10 AU at 29 pc) east of HD 75289. A second SofI image

taken 10 months later confirmed the common proper motion of HD 75289 B

with its host star. The infrared spectrum and colors of the companion

are consistent with an M 2 to M 5 main-sequence star at the distance of

HD 75289. No further (sub)stellar companion down to H=19 mag could be

detected. With the SofI detection limit we can rule out additional

stellar companions beyond 140 AU and substellar companions with masses

m≥0.050 M⊙ from 400 AU up to 2000 AU.

Based on observations obtained on La Silla in ESO programs 68.C-008 and

70.C-0116(A).

Organisation(s)

Department of Astrophysics

External organisation(s)

Thüringer Landessternwarte Tautenburg, European Southern Observatory (Germany), Friedrich-Schiller-Universität Jena, Tel Aviv University

Journal

Astronomy & Astrophysics

Volume

425

Pages

249-253

ISSN

0004-6361

DOI

https://doi.org/10.1051/0004-6361:20041009

Publication date

10-2004

Peer reviewed

Yes

Keywords

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