Simulation of a Space-based Microlensing Survey for Terrestrial Extrasolar Planets
Simulation of a Space-based Microlensing Survey for Terrestrial Extrasolar Planets
复制标题
对太阳系外行星的天基微透镜勘测的模拟
DOI：
10.1086/340977
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
S. Rhie
中科院分区：
文献类型：
--
作者：
D. Bennett;S. Rhie
我们表明，对太阳系外行星进行天基引力微透镜勘测在不久的将来是可行的，并且可以提供银河系行星系统特性的近乎完整的图像。我们使用具有约 2 deg2 视场的 1-2 m 孔径太空望远镜对此类调查进行模拟，以连续监测约 108 颗银河核球主序星。微透镜技术可以发现具有高信噪比的低质量行星，而我们研究的太空任务对质量与火星一样低的行星很敏感。通过瞄准只能从太空中解析的主序源恒星，天基微透镜巡天能够探测到来自透镜体恒星的足够光，以确定三分之一具有检测到行星的透镜体恒星的光谱类型，包括几乎所有的 F、G 和 K 星，它们构成了事件样本的四分之一。这使得能够确定行星质量和物理单位的距离，以及行星的丰度作为恒星类型和距银河中心距离的函数。我们表明，天基微透镜行星搜索程序对轨道间隔为 0.7-10 天文单位的行星具有最高的灵敏度，但它在更大的间隔下也具有显着的灵敏度，并且能够探测大量自由漂浮的行星。这补充了计划中的类地行星凌日任务，该任务对间距≤1天文单位的类地行星敏感。这样的任务还应该通过凌日探测到约 50,000 颗巨行星，因此，它是唯一提出的对所有轨道半径的行星都敏感的行星探测方法。
We show that a space-based gravitational microlensing survey for terrestrial extrasolar planets is feasible in the near future and could provide a nearly complete picture of the properties of planetary systems in our Galaxy. We present simulations of such a survey using a 1-2 m aperture space telescope with a ~2 deg2 field of view to continuously monitor ~108 Galactic bulge main-sequence stars. The microlensing techniques allow the discovery of low-mass planets with high signal-to-noise ratio, and the space missions that we have studied are sensitive to planets with masses as low as that of Mars. By targeting main-sequence source stars, which can only be resolved from space, the space-based microlensing survey is able to detect enough light from the lens stars to determine the spectral type of one-third of the lens stars with detected planets, including virtually all of the F, G, and K stars, which comprise one-quarter of the event sample. This enables the determination of the planetary masses and separations in physical units as well as the abundance of planets as a function of stellar type and distance from the Galactic center. We show that a space-based microlensing planet search program has its highest sensitivity to planets at orbital separations of 0.7-10 AU, but it will also have significant sensitivity at larger separations and will be able to detect free-floating planets in significant numbers. This complements the planned terrestrial planet transit missions, which are sensitive to terrestrial planets at separations of ≤1 AU. Such a mission should also detect ~50,000 giant planets via transits, and it is, therefore, the only proposed planet detection method that is sensitive to planets at all orbital radii.
影响因子：
3.2
作者：
V. Mannings;A. Boss;S. Russell
通讯作者：
V. Mannings;A. Boss;S. Russell