Visual orbit for the low-mass binary Gliese 22 AC from speckle interferometry

J. Woitas; V. S. Tamazian; J. A. Docobo; Ch. Leinert

doi:10.1051/0004-6361:20030756

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arXiv · astro-ph/0305330

Visual orbit for the low-mass binary Gliese 22 AC from speckle interferometry

J. Woitas·V. S. Tamazian·J. A. Docobo·Ch. Leinert

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Abstract

Based on 14 data points obtained with near-infrared speckle interferometry and covering an almost entire revolution, we present a first visual orbit for the low-mass binary system Gliese 22 AC. The quality of the orbit is largely improved with respect to previous astrometric solutions. The dynamical system mass is 0.592 +- 0.065 solar masses, where the largest part of the error is due to the Hipparcos parallax. A comparison of this dynamical mass with mass-luminosity relations on the lower main sequence and theoretical evolutionary models for low-mass objects shows that both probably underestimate the masses of M dwarfs. A mass estimate for the companion Gliese 22 C indicates that this object is a very low-mass star with a mass close to the hydrogen burning mass limit.

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J. Woitas, V. S. Tamazian, J. A. Docobo, Ch. Leinert. 2003-05-19. Visual orbit for the low-mass binary Gliese 22 AC from speckle interferometry. https://doi.org/10.1051/0004-6361%3A20030756

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