Meeting the Cool Neighbors III: Spectroscopy of Northern NLTT Stars
نویسندگان
چکیده
We present initial results of an all-sky search for late-type dwarfs within 20 pc of the Sun using the New Luyten Two-Tenths (NLTT) catalog cross-referenced with the 2-Micron All Sky Survey (2MASS) database. The results were obtained with low-resolution optical spectroscopic follow-up of candidate nearby-stars as a preliminary test of our methodology. MJ , derived using spectral indices, and 2MASS J are used to estimate distances. Out of the 70 objects observed, 28 are identified as previously unrecognized objects within 25 pc of the Sun, and up to 19 of these are within 20 pc. One, LP 64713 is an M9-type dwarf at 10.5 pc making it one of the four closest M9 dwarfs currently known. We also discuss the chromospheric activity of the observed dwarfs. Subject headings: galaxy: stellar content — Solar Neighborhood — stars: distances — stars: late-type dwarfs Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the National Science Foundation.
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تاریخ انتشار 2002