The Discovery of a Nearby M Dwarf

Ohad Shemmer; Shai Kaspi

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arXiv · astro-ph/9811195

The Discovery of a Nearby M Dwarf

Ohad Shemmer·Shai Kaspi

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Abstract

We report the discovery of a nearby M dwarf star, found accidentally while observing the old nova DN Gem at the Wise Observatory. The star is designated 1200-05296925 in the PMM USNO-A1.0 catalogue and its coordinates, calculated for 1997 November 27 are: RA=6 55 05.13 Dec = +32 09 54.1 (Equinox J2000, Epoch J1997.90). Astrometric measurements for the star yielded a yearly proper motion rate of 0.155$\pm$0.002 arcseconds in right ascension and negligible yearly proper motion rate in declination. The apparent V magnitude of the star was measured as m_V=13.87$\pm$0.16 mag and spectral identification yielded a spectral type of M3.5Ve$\pm$0.5 subclasses. Using relations between spectral type and absolute V magnitude in M dwarfs, we arrive at an absolute magnitude of M_V=12.3^{+1.2}_{-1.1} mag, which corresponds to a distance of 21^{+15}_{-10} pc.

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Ohad Shemmer, Shai Kaspi. 1998-11-12. The Discovery of a Nearby M Dwarf. https://arxiv.org/abs/astro-ph/9811195

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