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arXiv · 1007.3981

Chandra X-ray Detection of the Enigmatic Field Star BP Psc

Joel H. Kastner·Rodolfo Montez Jr.·David Rodriguez·Nicolas Grosso·B. Zuckerman·Marshall D. Perrin·Thierry Forveille·James R. Graham
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Abstract

BP Psc is a remarkable emission-line field star that is orbited by a dusty disk and drives a parsec-scale system of jets. We report the detection by the Chandra X-ray Observatory of a weak X-ray point source coincident with the centroids of optical/IR and submillimeter continuum emission at BP Psc. As the star's photosphere is obscured throughout the visible and near-infrared, the Chandra X-ray source likely represents the first detection of BP Psc itself. The X-rays most likely originate with magnetic activity at BP Psc and hence can be attributed either to a stellar corona or to star-disk interactions. The log of the ratio of X-ray to bolometric luminosity (log(L_X/L_{bol}) lies in the range -5.8 to -4.2. This is smaller than log(L_X/L_{bol}) ratios typical of low-mass, pre-main sequence stars, but is well within the log(L_X/L_{bol}) range observed for rapidly-rotating (FK Com-type) G giant stars. Hence, the Chandra results favor an exotic model wherein the disk/jet system of BP Psc is the result of its very recently engulfing a companion star or giant planet, as the primary star ascended the giant branch.

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Joel H. Kastner, Rodolfo Montez Jr., David Rodriguez, Nicolas Grosso, B. Zuckerman, Marshall D. Perrin, Thierry Forveille, James R. Graham. 2010-07-22. Chandra X-ray Detection of the Enigmatic Field Star BP Psc. https://doi.org/10.1088/2041-8205%2F719%2F1%2Fl65

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