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A WN4 companion to BD +62 2296 in Cas OB5

Ignacio Negueruela
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Abstract

I report observations of the triple system BD +62 2296 showing that all its components are early-type stars, most likely physically related. The faintest component BD +62 2296B is a hitherto uncatalogued Wolf-Rayet star. The brightest component, star A, is shown to be a seemingly normal B2.5Ia supergiant. Long-slit spectroscopy of BD +62 2296B shows it to be a narrow-lined WN4 star. Given the spatial separation, the two objects are unlikely to form a physical binary. Spectra of the third visual component, BD +62 2296C, allow its classification as a B0III star. Such concentration of massive stars strongly suggests that BD +62 2296 is in reality a very compact young open cluster in the area of the OB association Cas OB5.

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Ignacio Negueruela. 2003-07-16. A WN4 companion to BD +62 2296 in Cas OB5. https://doi.org/10.1051/0004-6361%3A20031089

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