天文学进展2011，Vol.29Issue(2)：123-131,9.
银河系旋臂结构和运动学的VLBI高精度探测
Probing the Spiral Structure and Kinematics of the Milky Way with VLBI Techniques
摘要
Abstract
A large project is being carried out by several groups throughout the world. The goal is to reinforce the foundations of models of the spiral structure of the Milky Way by measuring distances directly to regions of star formation across the Milky Way using VLBI techniques. The way is to determine trigonometric parallaxes to strong maser sources, which are associated with regions of star formation and their attendant HII regions. With accurate distances, one should be able to determine the locations of the spiral arms, and produce an extensive map of the 3dimensional structure of bright material associated with young stars that define spiral structure.In addition to distances, the project also yields excellent measurements of secular proper motions,with accuracies of 1 km·s-1. Combining radial velocity measurements with proper motions (and distances) yields full 3-dimensional velocities, relative to the motion of the Sun. Thus, through this project, one will also determine the full kinematics of star forming regions in the Milky Way, which will accurately define the rotation curve of the Milky Way and, in turn, its enclosed mass as a function of Galactocentric radius. Finally, one should be able to show how material in spiral arms actually moves, to characterize the occasional large kinematic anomalies (such as in the Perseus Arm), and hopefully to understand why these anomalies occur. At present, the preliminary results indicate that our galaxy is more massive and spins much faster than previously thought.关键词
银河系结构/三角视差/天体脉泽Key words
structure of the Milky Way/ masers/ kinematics分类
天文与地球科学引用本文复制引用
徐烨..银河系旋臂结构和运动学的VLBI高精度探测[J].天文学进展,2011,29(2):123-131,9.基金项目
国家自然科学基金(11073054,10733030) （11073054,10733030）
国家自然科学基金创新群体(10621303) （10621303）
973计划(2007CB815403) （2007CB815403）
