Discovery of X-ray flaring on the magnetic Bp-star sigma Ori E

D. Groote; J. H. M. M. Schmitt

doi:10.1051/0004-6361:20034300

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arXiv · astro-ph/0402437

Discovery of X-ray flaring on the magnetic Bp-star sigma Ori E

D. Groote·J. H. M. M. Schmitt

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Abstract

We report the detection of an X-ray flare on the Bp star sigma 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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D. Groote, J. H. M. M. Schmitt. 2004-02-18. Discovery of X-ray flaring on the magnetic Bp-star sigma Ori E. https://doi.org/10.1051/0004-6361%3A20034300

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