标题： BP Psc域星的钱德拉X射线探测 显示英文标题

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

摘要： BP Psc是一颗显著的发射线场星，被一个尘埃盘环绕，并驱动着一个以秒差距为尺度的喷流系统。 我们报告了通过钱德拉X射线天文台检测到的一个微弱的X射线点源，该点源与BP Psc光学/红外和亚毫米连续辐射的质心一致。 由于恒星的光球在整个可见光和近红外波段都被遮蔽，钱德拉X射线源很可能代表了BP Psc本身的首次探测。 X射线最可能起源于BP Psc的磁场活动，因此可以归因于恒星的日冕或恒星-盘相互作用。 X射线与总辐射亮度比值的对数(log(L_X/L_{布尔}))范围在-5.8到-4.2之间。 这比低质量、前主序星典型的log(L_X/L_{布尔})比值小，但与快速旋转（FK Com型）G巨星观测到的log(L_X/L_{布尔})范围一致。 因此，钱德拉的结果支持一种奇特的模型，即BP Psc的盘/喷流系统的形成是由于主星刚刚吞噬了一颗伴星或巨型行星，当主星上升到巨星分支时。 显示英文摘要

摘要： 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.