期刊
ASTROPHYSICAL JOURNAL
卷 872, 期 2, 页码 -出版社
IOP Publishing Ltd
DOI: 10.3847/1538-4357/ab0104
关键词
Galaxy: disk; Galaxy: fundamental parameters; Galaxy: kinematics and dynamics; Galaxy: structure; solar neighborhood
资金
- National Natural Science Foundation of China [11890694, 11390371]
Gaia DR2 data are used to calculate the Oort constants and derive the Galactic rotational properties in this work. We choose the solar vicinity stars with a clean sample within 500 pc. The Oort constants are then fitted through the relation between the proper motions as a function of Galactic longitude l. A maximum likelihood method is adopted to obtain the Oort constants and the uncertainties are produced by a Markov Chain Monte Carlo technique with the sample. Our results for the Oort constants are A = 15.1 +/- 0.1 kms(-1) kpc(-1), B = -13.4 +/- 0.1 kms(-1) kpc(-1), C = -2.7 +/- 0.1 kms(-1) kpc(-1), and K = -1.7 +/- 0.2 kms(-1) kpc(-1) respectively. The nonzero values of C and K represent a nonaxisymmetric model for the Galaxy. According to our results, the angular velocity Omega = vertical bar A - B vertical bar = 28.5. 0.1 km s(-1) kpc(-1) and the circular velocity decreases in solar vicinity. The local radial velocity also decreases along the radial direction due to C + K being negative.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据