Stellar wind–magnetosphere interaction at exoplanets: computations of auroral radio powers
Stellar wind–magnetosphere interaction at exoplanets: computations of auroral radio powers
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系外行星上的恒星风-磁层相互作用：极光无线电功率的计算
DOI：
10.1093/mnras/stw1430
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发表时间：
2016
影响因子：
4.8
通讯作者：
S. Milan
中科院分区：
文献类型：
--
作者：
J. Nichols;S. Milan
我们提出了由类地磁层与太阳风相互作用驱动的具有磁层的系外行星预期的极光无线电功率的计算。具体来说，我们计算由白天和夜晚磁重联驱动的邓吉循环过程产生的双细胞涡旋电离层流、电流和由此产生的无线电功率，作为行星轨道距离和磁场强度的函数。我们包括在地球磁层观察到的磁层对流的饱和度，并且我们提出了对流势、无线电功率和谱通量密度的幂律近似。我们特别考虑太阳年龄系统和年轻（1 Gyr）系统。我们表明，对于具有饱和对流势的磁层，无线电功率随着磁场强度的增加而增加，并且随着轨道距离的增加而广泛减少。我们表明，热木星的磁层对流将饱和，因此无法耗散全部可用的入射坡印廷通量，因此磁辐射波德定律（RBL）对热木星的无线电功率有很大的高估。对于场强为 0.1–10 B 的热木星，我们的热木星无线电功率为 ∼5–1300 TW
J 围绕类太阳恒星运行，而我们发现，对于围绕年轻类太阳恒星运行的热木星来说，竞争效应会产生基本相同的功率。然而，特别是对于磁场较弱的行星，我们在较大轨道距离处的功率比 RBL 给出的功率更高，并且预计使用 SKA 可以检测到许多行星的配置。
We present calculations of the auroral radio powers expected from exoplanets with magnetospheres driven by an Earth-like magnetospheric interaction with the solar wind. Specifically, we compute the twin cell-vortical ionospheric flows, currents, and resulting radio powers resulting from a Dungey cycle process driven by dayside and nightside magnetic reconnection, as a function of planetary orbital distance and magnetic field strength. We include saturation of the magnetospheric convection, as observed at the terrestrial magnetosphere, and we present power-law approximations for the convection potentials, radio powers and spectral flux densities. We specifically consider a solar-age system and a young (1 Gyr) system. We show that the radio power increases with magnetic field strength for magnetospheres with saturated convection potential, and broadly decreases with increasing orbital distance. We show that the magnetospheric convection at hot Jupiters will be saturated, and thus unable to dissipate the full available incident Poynting flux, such that the magnetic Radiometric Bode's Law (RBL) presents a substantial overestimation of the radio powers for hot Jupiters. Our radio powers for hot Jupiters are ∼5–1300 TW for hot Jupiters with field strengths of 0.1–10 B
J orbiting a Sun-like star, while we find that competing effects yield essentially identical powers for hot Jupiters orbiting a young Sun-like star. However, in particular, for planets with weaker magnetic fields, our powers are higher at larger orbital distances than given by the RBL, and there are many configurations of planet that are expected to be detectable using SKA.
亚阿尔弗尼克行星恒星和月球行星相互作用中的磁能通量
影响因子：
6.5
作者：
Grambusch;Duling;Neubauer
通讯作者：
Neubauer
太阳系外巨行星大气的电离
DOI：
10.1088/0004-637x/722/1/178
发表时间：
2010
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Koskinen T
通讯作者：
Koskinen T