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arXiv · 1502.02712

A New Luminous Blue Variable in M31

Roberta M. Humphreys·John C. Martin·Michael S. Gordon
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Abstract

We report the fifth confirmed Luminous Blue Variable/S Doradus variable in M31. In 2006, J004526.62+415006.3 had the spectrum of hot Fe II emission line star with strong P Cygni profiles in the Balmer lines. In 2010, its absorption line spectrum resembled an early A-type supergiant with H and Fe II emission lines with strong P Cygni profiles, and in 2013 the spectrum had fully transitioned to an F-type supergiant due to the formation of the optically thick, cool wind which characterizes LBVs at maximum light. The photometric record supports the LBV/S Dor nature of the variability. Its bolometric luminosity ~ -9.65 mag places it on the HR Diagram near the known LBVs, AE And, Var C in M33 and S Dor.

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Roberta M. Humphreys, John C. Martin, Michael S. Gordon. 2015-02-09. A New Luminous Blue Variable in M31. https://doi.org/10.1086/681013

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