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Deconstructing HD 28867

Frederick M. Walter·Tracy L. Beck·Jon A. Morse·Scott J. Wolk
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Abstract

The 3" pair of B9 stars, HD 28867, is one of the brightest X-ray sources in the Taurus-Auriga star forming region. In this multi-wavelength study, we attempt to deduce the source of the X-ray emission. We show that the East component is the X-ray source. The East component has a near-IR excess and displays narrow absorption lines in the optical, both of which are consistent with a cool stellar companion. This companion is one of the brightest low mass pre-main sequence stars in Tau-Aur; at 2 microns it and the B9 star are equally bright. We see evidence for radial velocity variability in the cool component of >34 km/s. It is not visible in K band speckle imaging, which constrains the companion to lie within 14 AU of the B star. We also report on a possible fourth member of the group, an M1 star 18" south of HD 28867.

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Frederick M. Walter, Tracy L. Beck, Jon A. Morse, Scott J. Wolk. 2002-12-31. Deconstructing HD 28867. https://doi.org/10.1086/368245

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