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The Massive Star Population in M101. III. Spectra and Photometry of the Luminous and Variable Stars

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 نشر من قبل Roberta Humphreys
 تاريخ النشر 2015
  مجال البحث فيزياء
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We discuss moderate resolution spectra, multicolor photometry, and light curves of thirty-one of the most luminous stars and variables in the giant spiral M101. The majority are intermediate A to F-type supergiants. We present new photometry and light curves for three known irregular blue variables V2, V4 and V9) and identify a new candidate. Their spectra and variability confirm that they are LBV candidates and V9 may be in an LBV-like maximum light state or eruption.



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