A circumbinary debris disk in a polluted white dwarf system
A circumbinary debris disk in a polluted white dwarf system
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DOI：
10.1038/s41550-016-0032
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发表时间：
2017-03-01
期刊：
影响因子：
14.1
通讯作者：
Gansicke, B. T.
中科院分区：
文献类型：
--
作者：
Farihi, J.;Parsons, S. G.;Gansicke, B. T.
行星系统通常在单星演化过程中幸存下来，就像观察到的围绕白矮星轨道运行并污染其表面的类地小行星碎片(1，2)所证明的那样。在这里，我们报告了一颗环绕着一颗白矮星和一颗亚星伴星围绕2.27小时轨道运行的环绕双星尘埃盘的识别。该系统具有大气金属污染和红外线过量(3，4)的双重特征；然而，标准(平坦和不透明)的磁盘配置动态地被二进制排除。取而代之的是，探测到的碎片储存库必须位于光学薄型的罗氏极限之外，那里恒星辐射的侵蚀相对较快。这一发现表明，在近距离双星附近，即使是低质量比的双星，岩石小行星的形成也是健壮的。
Planetary systems commonly survive the evolution of single stars, as evidenced by terrestrial-like planetesimal debris observed orbiting and polluting the surfaces of white dwarfs(1,2). Here, we report the identification of a circumbinary dust disk surrounding a white dwarf with a substellar companion in a 2.27 h orbit. The system bears the dual hallmarks of atmospheric metal pollution and infrared excess(3,4); however, the standard (flat and opaque) disk configuration is dynamically precluded by the binary. Instead, the detected reservoir of debris must lie well beyond the Roche limit in an optically thin configuration, where erosion by stellar irradiation is relatively rapid. This finding shows that rocky planetesimal formation is robust around close binaries, even those with low mass ratios.