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arXiv · 1306.0368

The low mass companion of HIP 45314 (HR 3672)

C. Adam·R. Neuhäuser·M. Mugrauer·J. G. Schmidt·T. O. B. Schmidt
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Abstract

We report the discovery of a very low-mass companion to HIP 45314 (HR 3672) located about 2.7 arcsec north-west of HR 3672 A. With four years of epoch difference between the two observations obtained with the Very Large Telescope we can reject by more than 4 sigma that B would be a non-moving background object unrelated to A. HR 3672 A is a B 7-8 main sequence star with an age of 140 \pm 80 Myr and from the magnitude difference between HR 3672 A and B and the 2MASS magnitudes, we can estimate the magnitude of HR 3672 B (K_{s}=12.42 \pm 0.28 mag) and then, for age and distance of the primary star, using models, its luminosity and mass (0.2-0.5 M_sun). We present a reanalysis of the probable membership of HR 3672 A to the Platais 9 cluster, and introduce a new method for astrometric calibration of data without dedicated calibration images. In the deepest available image (co-add of all epochs) no additional companion candidates within 13 arcsec were detected down to 0.03 M_sun.

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C. Adam, R. Neuhäuser, M. Mugrauer, J. G. Schmidt, T. O. B. Schmidt. 2013-06-03. The low mass companion of HIP 45314 (HR 3672). https://doi.org/10.1093/mnras%2Fstt733

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