Discovery of X - ray flaring on the magnetic Bp - star σ Ori
نویسندگان
چکیده
We report the detection of an X-ray flare on the Bp star σ Ori E with the ROSAT high resolution imager (HRI). The flare is shown to have likely occurred on the early-type star, rather than on an hypothesized late-type companion. We derive flare parameters such as total energy release, coarse estimates of size and density, and also present arguments for a magnetic origin of the flare. We place our observations in the context of a magnetic character of Bp-type stars and speculate on a common physical basis and connection between Bp and Be stars.
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