MASS TRANSFER, TRANSITING STREAM, AND MAGNETOPAUSE IN CLOSE-IN EXOPLANETARY SYSTEMS WITH APPLICATIONS TO WASP-12
MASS TRANSFER, TRANSITING STREAM, AND MAGNETOPAUSE IN CLOSE-IN EXOPLANETARY SYSTEMS WITH APPLICATIONS TO WASP-12
复制标题
近地外行星系统中的传质、凌日流和磁层顶及其在 WASP-12 中的应用
DOI：
10.1088/0004-637x/721/2/923
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
E. V. D. van den Heuvel
中科院分区：
文献类型：
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作者：
D. Lai;C. Helling;E. V. D. van den Heuvel
我们研究了近距离系外行星系统中洛希瓣溢出的质量传递。行星的大气气体通过内拉格朗日点，并沿着一条狭窄的气流，加速到100-200 km s−1的速度，然后形成一个吸积盘。我们表明，圆柱形的吸积流可以有一个面积（投影在天空的平面）相媲美的行星和一个显着的光学深度光谱线吸收。这种“凌日柱体”可能会产生行星凌日的早期进入，正如哈勃太空望远镜最近对WASP-12系统的观测所表明的那样。吸积流产生的不对称盘也可能导致星光随时间变化的模糊和明显的早期进入。我们还考虑了恒星风与行星磁层的相互作用。由于风速为亚音速/亚阿尔夫文风速，并且与行星的轨道速度相当，因此磁层顶的头部相对于星下线（连接行星和星星的线）位于东方。磁层顶周围的气体如果被充分压缩，可能会在行星过境期间产生不对称的进出，尽管需要更多的工作来评估这种可能性。
We study mass transfer by Roche lobe overflow in close-in exoplanetary systems. The planet's atmospheric gas passes through the inner Lagrangian point and flows along a narrow stream, accelerating to 100–200 km s−1 velocity before forming an accretion disk. We show that the cylinder-shaped accretion stream can have an area (projected in the plane of the sky) comparable to that of the planet and a significant optical depth to spectral line absorption. Such a “transiting cylinder” may produce an earlier ingress of the planet transit, as suggested by recent Hubble Space Telescope observations of the WASP-12 system. The asymmetric disk produced by the accretion stream may also lead to time-dependent obscuration of the starlight and apparent earlier ingress. We also consider the interaction of the stellar wind with the planetary magnetosphere. Since the wind speed is subsonic/sub-Alfvénic and comparable to the orbital velocity of the planet, the head of the magnetopause lies eastward relative to the substellar line (the line joining the planet and the star). The gas around the magnetopause may, if sufficiently compressed, give rise to asymmetric ingress/egress during the planet transit, although more works are needed to evaluate this possibility.
在系外行星 WASP-12b 的轨道上
DOI：
10.1088/0004-637x/727/2/125
发表时间：
2011
期刊：
The Astrophysical Journal
影响因子：
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作者：
Campo C
通讯作者：
Campo C