TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. V. G23.01−0.41 AND G23.44−0.18
TRIGONOMETRIC PARALLAXES OF MASSIVE STAR-FORMING REGIONS. V. G23.01−0.41 AND G23.44−0.18
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DOI：
10.1088/0004-637x/693/1/424
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发表时间：
2008-11
期刊：
影响因子：
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通讯作者：
A. Brunthaler;M. Reid;K. Menten;X. Zheng;L. Moscadelli;Y. X. M. F. Radioastronomie;H. C. F. Astrophysics;N. University;O. Arcetri;Purple Mountain Observatory
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文献类型：
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作者：
A. Brunthaler;M. Reid;K. Menten;X. Zheng;L. Moscadelli;Y. X. M. F. Radioastronomie;H. C. F. Astrophysics;N. University;O. Arcetri;Purple Mountain Observatory
我们报告了大质量恒星形成区G23.01−0.41和G23.44−0.18的三角视差，分别对应于4.59+0.38−0.33 kpc和5.88+1.37−0.93 kpc的距离。到G23.01−0.41的距离小于银河系标准模型下的近运动学距离，也小于通常假设的远运动学距离的一半。这使它位于十字座-盾牌座旋臂中，而G23.44−0.18的距离接近于它的近运动学距离，很可能位于银河棒末端附近的诺玛旋臂中。将距离和自行与观测到的径向速度结合起来，就可以给出恒星形成区的位置和整个空间的运动。我们发现这些源与银河系圆形轨道有很大的偏差：两个源都显示出20-30 km s-1的奇特运动，与银河系自转相反，并朝向银河系中心。这些巨大的奇特运动可能是银河棒引力扰动的结果。
We report trigonometric parallaxes for the massive star-forming regions G23.01−0.41 and G23.44−0.18, corresponding to distances of 4.59+0.38−0.33 kpc and 5.88+1.37−0.93 kpc, respectively. The distance to G23.01−0.41 is smaller than its near kinematic distance assuming a standard model of the Milky Way and less than half of its far kinematic distance, which has usually been assumed. This places it in the Crux-Scutum spiral arm. The distance to G23.44−0.18 is close to its near kinematic distance and most likely places it in the Norma spiral arm near the end of the Galactic bar. Combining the distance and proper motions with observed radial velocities gives the location and full space motion of the star-forming regions. We find large deviations from circular Galactic orbits for these sources: both sources show peculiar motions of 20–30 km s−1 counter to Galactic rotation and toward the Galactic center. These large peculiar motions might be the result of gravitational perturbations from the Galactic bar.