A Multiwavelength Radial Velocity Search for Planets around the Brown Dwarf LP 944-20
A Multiwavelength Radial Velocity Search for Planets around the Brown Dwarf LP 944-20
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褐矮星周围行星的多波长径向速度搜索 LP 944-20
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
R. Wainscoat
中科院分区：
文献类型：
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作者：
E. L. Martín;E. L. Martín;E. Guenther;M. R. Z. Osorio;H. Bouy;R. Wainscoat
我们分别使用VLT/UVES和Keck/NIRSPEC在光学和近红外波段对附近的褐矮星LP 944-20进行了径向速度变化的监测。UVES径向速度数据超过14个晚上，跨越841天的基线显示出显着的变化幅度为3.5公里s-1。UVES数据的周期图分析表明，一个可能的周期在2.5和3.7小时之间，这可能是由于褐矮星的旋转。然而，NIRSPEC的数据超过6夜显示的均方根色散只有0.36公里s-1，不遵循的周期性趋势。这些结果表明，与UVES看到的变化可能是由于旋转调制不均匀的表面特征。我们认为，未来的行星搜索非常低质量的恒星和褐矮星使用径向速度将更好地进行在近红外比光学。
The nearby brown dwarf LP 944-20 has been monitored for radial velocity variability at optical and near-infrared wavelengths using the VLT/UVES and the Keck/NIRSPEC, respectively. The UVES radial velocity data obtained over 14 nights spanning a baseline of 841 days show significant variability with an amplitude of 3.5 km s-1. The periodogram analysis of the UVES data indicates a possible period between 2.5 and 3.7 hr, which is likely due to the rotation of the brown dwarf. However, the NIRSPEC data obtained over 6 nights show an rms dispersion of only 0.36 km s-1 and do not follow the periodic trend. These results indicate that the variability seen with UVES is likely to be due to rotationally modulated inhomogeneous surface features. We suggest that future planet searches around very low mass stars and brown dwarfs using radial velocities will be better conducted in the near-infrared than in the optical.