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Discovery of a new Wolf-Rayet star using SAGE-LMC

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 نشر من قبل Andr\\'e-Nicolas Chen\\'e
 تاريخ النشر 2011
  مجال البحث فيزياء
والبحث باللغة English
 تأليف V.V. Gvaramadze




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We report the first-ever discovery of an extragalactic Wolf-Rayet (WR)star with Spitzer. A new WR star in the Large Magellanic Cloud (LMC) was revealed via detection of its circumstellar shell using 24 {mu}m images obtained in the framework of the Spitzer Survey of the Large Magellanic Cloud (SAGE-LMC). Subsequent spectroscopic bservations with the Gemini South resolved the central star in two components, one of which is a WN3b+abs star, while the second one is a B0V star. We consider the lopsided brightness distribution over the circumstellar shell as an indication that the WR star is a runaway and use this interpretation to identify a possible parent cluster of the star.



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