The Galactic Center: Improved Relative Astrometry for Velocities, Accelerations, and Orbits near the Supermassive Black Hole
The Galactic Center: Improved Relative Astrometry for Velocities, Accelerations, and Orbits near the Supermassive Black Hole
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银河中心：改进超大质量黑洞附近速度、加速度和轨道的相对天体测量学
DOI：
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发表时间：
2019
影响因子：
4.9
通讯作者：
K. Matthews
中科院分区：
文献类型：
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作者：
S. Jia;Jessica R. Lu;S. Sakai;A. Gautam;T. Do;M. Hosek;A. Ghez;E. Gallego;R. Schödel;A. Hees;A. Hees;M. Morris;E. Becklin;K. Matthews
我们提出了改进的相对天体测量的基础上获得的数据与10米W的银河系中心（GC）的中央半秒差距内的恒星。M. 1995年至2017年的凯克天文台。用于提高天体测量精度和准确度的新方法包括校正局部天体测量失真，应用星等相关的附加误差，以及更仔细地消除恒星混淆的情况。此外，我们采用刀切法来计算速度和加速度的不确定性。对于我们在中心10″（0.4 pc）的1184颗恒星的完整样本，得到的自行不确定性中位数为0.05 mas yr−1。我们已经探测到了24个加速源，比以前公布的加速源数量多2.6倍，这些加速源从黑洞延伸到4″（0.16 pc）。基于S 0 -2的轨道，我们新的天体测量分析将超大质量黑洞（SMBH）的系统误差降低了2倍。我们的天体测量参考系中的线性漂移在南北方向上也减少了4倍。我们还在GC中发现了第一个潜在的天体测量双星候选者S 0 -27。这些天体测量的改进为今后研究SMBH周围年轻恒星的起源和动力学、老核星星团的结构和动力学、SMBH的轨道性质以及强引力场中广义相对论的检验提供了基础。
We present improved relative astrometry for stars within the central half parsec of our Galactic Center (GC) based on data obtained with the 10 m W. M. Keck Observatory from 1995 to 2017. The new methods used to improve the astrometric precision and accuracy include correcting for local astrometric distortions, applying a magnitude-dependent additive error, and more carefully removing instances of stellar confusion. Additionally, we adopt jackknife methods to calculate velocity and acceleration uncertainties. The resulting median proper motion uncertainty is 0.05 mas yr−1 for our complete sample of 1184 stars in the central 10″ (0.4 pc). We have detected 24 accelerating sources, 2.6 times more than the number of previously published accelerating sources, which extend out to 4″ (0.16 pc) from the black hole. Based on S0-2's orbit, our new astrometric analysis has reduced the systematic error of the supermassive black hole (SMBH) by a factor of 2. The linear drift in our astrometric reference frame is also reduced in the north–south direction by a factor of 4. We also find the first potential astrometric binary candidate S0-27 in the GC. These astrometric improvements provide a foundation for future studies of the origin and dynamics of the young stars around the SMBH, the structure and dynamics of the old nuclear star cluster, the SMBH’s properties derived from orbits, and tests of general relativity in a strong gravitational field.
DOI：
10.1088/0004-637x/708/1/834
发表时间：
2009-08
期刊：
The Astrophysical Journal
影响因子：
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作者：
H. Bartko;Fabrice Martins;S. Trippe;T. Fritz;R. Genzel;T. Ott;F. Eisenhauer;S. Gillessen;
通讯作者：
H. Bartko;Fabrice Martins;S. Trippe;T. Fritz;R. Genzel;T. Ott;F. Eisenhauer;S. Gillessen;