The Sun as a planet-host star: proxies from SDO images for HARPS radial-velocity variations
The Sun as a planet-host star: proxies from SDO images for HARPS radial-velocity variations
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太阳作为行星宿主恒星：来自 SDO 图像的 HARPS 径向速度变化代理
DOI：
10.1093/mnras/stw187
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发表时间：
2016
影响因子：
4.8
通讯作者：
Haywood R
中科院分区：
文献类型：
--
作者：
Haywood R
太阳是唯一一颗表面可以直接高分辨率解析的星星，因此构成了探索恒星径向速度（RV）变化物理起源的绝佳测试案例。我们提出了HARPS观测的阳光散射的明亮的小行星4/灶神星，从中我们推导出太阳的活动驱动的RV变化。与此同时，太阳动力学观测站上的日震和磁成像仪仪器为我们提供了Fei 6173日冕谱线上太阳的同步高空间分辨率磁图、多普勒图和连续图像。我们确定RV调制所产生的抑制颗粒蓝移磁化区域和暗斑和亮光斑引起的磁通量不平衡。这些贡献的均方根速度幅值分别为2.40和0.41 m s-1，这证实了对流的抑制是活动引起的RV变化的主要来源。我们发现斑点和斑区的多普勒不平衡只有弱相关。因此，光变曲线只能给出对流蓝移抑制的不完全预测。相反，我们必须寻找直接跟踪可见恒星半球上的谱斑覆盖的代理。由HARPS谱导出的色球通量指数在这方面表现不佳，可能是由于色球和光球临边增亮/变暗的差异。我们还发现，活动驱动的RV变化的太阳是强烈相关的，其全磁盘磁通量密度，这可能成为一个有用的代理活动相关的RV噪声。
The Sun is the only star whose surface can be directly resolved at high resolution, and therefore constitutes an excellent test case to explore the physical origin of stellar radial-velocity (RV) variability. We present HARPS observations of sunlight scattered off the bright asteroid 4/Vesta, from which we deduced the Sun's activity-driven RV variations. In parallel, the Helioseismic and Magnetic Imager instrument on board theSolar Dynamics Observatoryprovided us with simultaneous high spatial resolution magnetograms, Dopplergrams and continuum images of the Sun in the Fei6173 Å line. We determine the RV modulation arising from the suppression of granular blueshift in magnetized regions and the flux imbalance induced by dark spots and bright faculae. The rms velocity amplitudes of these contributions are 2.40 and 0.41 m s−1, respectively, which confirms that the inhibition of convection is the dominant source of activity-induced RV variations at play, in accordance with previous studies. We find the Doppler imbalances of spot and plage regions to be only weakly anticorrelated. Light curves can thus only give incomplete predictions of convective blueshift suppression. We must instead seek proxies that track the plage coverage on the visible stellar hemisphere directly. The chromospheric flux indexderived from the HARPS spectra performs poorly in this respect, possibly because of the differences in limb brightening/darkening in the chromosphere and photosphere. We also find that the activity-driven RV variations of the Sun are strongly correlated with its full-disc magnetic flux density, which may become a useful proxy for activity-related RV noise.
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影响因子：
6.5
作者：
M. Desort;A. Lagrange;F. Galland;S. Udry;M. Mayor
通讯作者：
M. Desort;A. Lagrange;F. Galland;S. Udry;M. Mayor
使用 MDI/SOHO 重建太阳积分径向速度
影响因子：
6.5
作者：
N. Meunier;A. Lagrange;M. Desort
通讯作者：
M. Desort
利用太阳来估计类地行星的探测能力。
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
S. Borgniet;N. Meunier;A. Lagrange
通讯作者：
A. Lagrange
HARPS 搜寻南系外行星 XVII。
影响因子：
6.5
作者：
C. Moutou;M. Mayor;G. Curto;S. Udry;F. Bouchy;W. Benz;C. Lovis;D. Naef;F. Pepe;D. Queloz;N. Santos
通讯作者：
N. Santos
光曲线和灶神星的颜色。
DOI：
10.1086/145493
发表时间：
1951
期刊：
The Astrophysical Journal
影响因子：
--
作者：
C. B. Stephenson
通讯作者：
C. B. Stephenson