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arXiv · 1502.00308

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

Skyler H. Grammer·Roberta M. Humphreys·Jill Gerke
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Abstract

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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Skyler H. Grammer, Roberta M. Humphreys, Jill Gerke. 2015-02-01. The Massive Star Population in M101. III. Spectra and Photometry of the Luminous and Variable Stars. https://doi.org/10.1088/0004-6256/149/5/152

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