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Variable dust formation by the colliding-wind Wolf-Rayet system HD 36402 in the Large Magellanic Cloud

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 نشر من قبل Peredur Williams
 تاريخ النشر 2013
  مجال البحث فيزياء
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 تأليف P. M. Williams




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Infrared photometry of the probable triple WC4(+O?)+O8I: Wolf-Rayet system HD 36402 (= BAT99-38) in the Large Magellanic Cloud (LMC) shows emission characteristic of heated dust. The dust emission is variable on a time-scale of years, with a period near 4.7 yr, possibly associated with orbital motion of the O8 supergiant and the inner P ~ 3.03-d WC4+O binary. The phase of maximum dust emission is close to that of the X-ray minimum, consistent with both processes being tied to colliding wind effects in an elliptical binary orbit. It is evident that Wolf-Rayet dust formation occurs also in metal-poor environments.



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