Adaptive optics observations of the galactic center young stars
Adaptive optics observations of the galactic center young stars
复制标题
银河系中心年轻恒星的自适应光学观测
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
M. Morris
中科院分区：
文献类型：
--
作者：
S. Yelda;A. Ghez;J. Lu;T. Do;L. Meyer;M. Morris
自适应光学观测极大地提高了银河系中心高角分辨率测量的质量和多功能性。在本文中，我们量化了自适应光学观测的质量，并报告了似乎驻留在中央秒差距恒星盘结构中的年轻恒星群的天体测量精度。我们证明，通过改进的天体测量学和 16 年的基线，包括 10 年的散斑和 6 年的激光导星 AO 成像，我们可以可靠地检测到天空平面上小至 70 μas yr-2 (~2.5 km s-1 yr-1) 的加速度，以及从超大质量黑洞投影半径为 1."5 (~0.06 pc) 的加速度。对加速度的敏感度提高了一倍比我们之前的努力大约增加了 6 个，我们能够直接探测年轻恒星盘的运动结构，它的内半径似乎为 0。”8。我们发现候选圆盘成员位于偏心轨道上，平均偏心率为 < e > = 0.30 ± 0.07。这种偏心率不能用具有正常初始质量函数的圆盘松弛来解释，这表明在初始偏心圆盘中存在头重脚轻的 IMF 或构造。
Adaptive Optics observations have dramatically improved the quality and versatility of high angular resolution measurements of the center of our Galaxy. In this paper, we quantify the quality of our Adaptive Optics observations and report on the astrometric precision for the young stellar population that appears to reside in a stellar disk structure in the central parsec. We show that with our improved astrometry and a 16 year baseline, including 10 years of speckle and 6 years of laser guide star AO imaging, we reliably detect accelerations in the plane of the sky as small as 70 μas yr-2 (~2.5 km s-1 yr-1) and out to a projected radius from the supermassive black hole of 1."5 (~0.06 pc). With an increase in sensitivity to accelerations by a factor of ~6 over our previous efforts, we are able to directly probe the kinematic structure of the young stellar disk, which appears to have an inner radius of 0."8. We find that candidate disk members are on eccentric orbits, with a mean eccentricity of < e > = 0.30 ± 0.07. Such eccentricities cannot be explained by the relaxation of a circular disk with a normal initial mass function, which suggests the existence of a top-heavy IMF or formation in an initially eccentric disk.
DOI：
10.1088/0004-637x/708/1/834
发表时间：
2009-08
期刊：
The Astrophysical Journal
影响因子：
--
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;