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Interferometric Observations of V838 Monocerotis

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 نشر من قبل Benjamin F. Lane
 تاريخ النشر 2005
  مجال البحث فيزياء
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 تأليف B. F. Lane




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We have used long-baseline near-IR interferometry to resolve the peculiar eruptive variable V838 Mon and to provide the first direct measurement of its angular size. Assuming a uniform disk model for the emission we derive an apparent angular diameter at the time of observations (November-December 2004) of $1.83 pm 0.06$ milli-arcseconds. For a nominal distance of $8pm2$ kpc, this implies a linear radius of $1570 pm 400 R_{odot}$. However, the data are somewhat better fit by elliptical disk or binary component models, and we suggest that the emission may be strongly affected by ejecta from the outburst.



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