Confirmation of the Luminous Blue Variable Status of MWC 930

A. S. Miroshnichenko; N. Manset; S. V. Zharikov; J. Zsargó; J. A. Juárez Jiménez; J. H. Groh; H. Levato; M. Grosso; R. J. Rudy; E. A. Laag; K. B. Crawford; R. C. Puetter; D. E. Reichart; K. M. Ivarsen; J. B. Haislip; M. C. Nysewander; A. P. LaCluyze

doi:10.1155/2014/130378

Advances in Astronomy (Jan 2014)

Confirmation of the Luminous Blue Variable Status of MWC 930

A. S. Miroshnichenko,
N. Manset,
S. V. Zharikov,
J. Zsargó,
J. A. Juárez Jiménez,
J. H. Groh,
H. Levato,
M. Grosso,
R. J. Rudy,
E. A. Laag,
K. B. Crawford,
R. C. Puetter,
D. E. Reichart,
K. M. Ivarsen,
J. B. Haislip,
M. C. Nysewander,
A. P. LaCluyze

Affiliations

A. S. Miroshnichenko: Department of Physics and Astronomy, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
N. Manset: CFHT Corporation, 65-1238 Mamalahoa Highway, Kamuela, HI 96743, USA
S. V. Zharikov: Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 877, 22830 Ensenada, BC, Mexico
J. Zsargó: Departimento de Físika, Escuela Superior de Física y Matematicas del Instituto Politecnico Nacional, Edif. 9, U. P. Zacatenco, 07738 Cuidad de Mexico, DF, Mexico
J. A. Juárez Jiménez: Departimento de Físika, Escuela Superior de Física y Matematicas del Instituto Politecnico Nacional, Edif. 9, U. P. Zacatenco, 07738 Cuidad de Mexico, DF, Mexico
J. H. Groh: Geneva Observatory, Geneva University, Chemin des Maillettes 51, 1290 Sauverny, Switzerland
H. Levato: Instituto de Ciencias Astronómicas de la Tierra y del Espacio, CONICET, Casilla de Correo 49, 5400 San Juan, Argentina
M. Grosso: Instituto de Ciencias Astronómicas de la Tierra y del Espacio, CONICET, Casilla de Correo 49, 5400 San Juan, Argentina
R. J. Rudy: The Aerospace Corporation, M2/266, P.O. Box 92957, Los Angeles, CA 90009, USA
E. A. Laag: The Aerospace Corporation, M2/266, P.O. Box 92957, Los Angeles, CA 90009, USA
K. B. Crawford: The Aerospace Corporation, M2/266, P.O. Box 92957, Los Angeles, CA 90009, USA
R. C. Puetter: Center for Astrophysics and Space Science, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
D. E. Reichart: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599, USA
K. M. Ivarsen: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599, USA
J. B. Haislip: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599, USA
M. C. Nysewander: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599, USA
A. P. LaCluyze: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599, USA

DOI: https://doi.org/10.1155/2014/130378
Journal volume & issue: Vol. 2014

Abstract

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We present spectroscopic and photometric observations of the emission-line star MWC 930 (V446 Sct) during its long-term optical brightening in 2006–2013. Based on our earlier data we suggested that the object has features found in Luminous Blue Variables (LBV), such as a high luminosity (~3 105 L⊙), a low wind terminal velocity (~140 km s−1), and a tendency to show strong brightness variations (~1 mag over 20 years). For the last ~7 years it has been exhibiting a continuous optical and near-IR brightening along with a change of the emission-line spectrum appearance and cooling of the star’s photosphere. We present the object’s V-band light curve, analyze the spectral variations, and compare the observed properties with those of other recognized Galactic LBVs, such as AG Car and HR Car. Overall we conclude the MWC 930 is a bona fide Galactic LBV that is currently in the middle of an S Dor cycle.

Published in Advances in Astronomy

ISSN: 1687-7969 (Print); 1687-7977 (Online)
Publisher: Wiley
Country of publisher: United Kingdom
LCC subjects: Science: Astronomy
Website: https://onlinelibrary.wiley.com/journal/5081

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