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Cool dwarfs in wide multiple systems: Paper I: Two mid-M dwarfs in a loosely-bound common-proper-motion pair

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 Publication date 2011
  fields Physics
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This is the first of a series of works devoted to investigate cool dwarfs in wide multiple systems. Here, I present Koenigstuhl 4 A and B, two bright, intermediate M dwarfs with a common high proper-motion and separated by 299 arcsec. At the most probable distance of the system, 19 pc, the projected physical separation is 5700 AU, which makes Koenigstuhl 4 AB to be one of the least bound binary systems with late-type components found to date. I also associate the primary with a ROSAT X-ray source for the first time.



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