DENIS-P J104814.7-395606.1: An M9 dwarfs at about 4 pc

X. Delfosse; T. Forveille; E. L. Martin; J. Guibert; J. Borsenberger; F. Crifo; C. Alard; N. Epchtein; P. Fouqué; G. Simon; F. Tajahmady

arXiv · astro-ph/0012168

DENIS-P J104814.7-395606.1: An M9 dwarfs at about 4 pc

X. Delfosse·T. Forveille·E. L. Martin·J. Guibert·J. Borsenberger·F. Crifo·C. Alard·N. Epchtein·P. Fouqué·G. Simon·F. Tajahmady

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Abstract

We present the discovery of a previously unknown member of the immediate solar neighbourhood, DENIS-P J104814.7-395606.1 (hereafter DENIS 1048-39), identified while mining the DENIS database for new nearby stars. A HIRES echelle spectrum obtained with the 10-m Keck telescope shows that it is an M9 dwarf. DENIS 1048-39 has a very bright apparent magnitude (I=12.67) for its spectral type and colour (I-J=3.07), and is therefore very nearby. If it is single its distance is only 4.1 +- 0.6pc, ranking it as between our twelfth and fortyth closest neighbour. It is also the closest star or brown dwarf with a spectral type later than M7V. Its proper motion was determined through comparison of Sky atlas Schmidt plates, scanned by the MAMA microdensitometer, with the DENIS images. At 1.53"/yr it further attests the closeness of DENIS 1048-39, and hence its dwarf status. These characteristics make it an obvious target for further detailed studies.

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X. Delfosse, T. Forveille, E. L. Martin, J. Guibert, J. Borsenberger, F. Crifo, C. Alard, N. Epchtein, P. Fouqué, G. Simon, F. Tajahmady. 2000-12-07. DENIS-P J104814.7-395606.1: An M9 dwarfs at about 4 pc. https://arxiv.org/abs/astro-ph/0012168

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