Trigonometric parallax measurement of a water maser source toward the Sgr D H II region
Trigonometric parallax measurement of a water maser source toward the Sgr D H II region
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Sgr D H II 区域水脉泽源的三角视差测量
DOI：
10.1093/pasj/psx039
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发表时间：
2017
影响因子：
2.3
通讯作者：
H. Kobayashi
中科院分区：
文献类型：
--
作者：
D. Sakai;T. Oyama;T. Nagayama;M. Honma;H. Kobayashi
我们报告的VLBI观测的水脉泽源与Sgr D Hiiregion，这是一个明亮的无线电连续源在银河系中心区域的方向。VLBI射电天体测量探测（VERA）测得的绝对自行和距离分别为（μαcos δ，μδ）=（−1.32 ± 0.15 mas yr−1，−2.86 ± 0.34 mas yr−1）和。水脉泽辐射的视速度与在Sgr D Hii区探测到的H 91 α复合线辐射的视速度相似。水脉泽发射的空间位置和视线速度表明，这个源是物理上与无线电连续观测下看到的扩展的Hiissima。因此，我们的研究结果表明，Sgr D Hiirregion位于银盘的盾牌臂。我们讨论这个新的观点的Sgr D复合体，视差和自行车的基础上。
We report on VLBI observations of a water maser source associated with the Sgr D Hiiregion, which is a bright radio continuum source in the direction of the Galactic center region. The absolute proper motions and the distance measured by VLBI Exploration of Radio Astrometry (VERA) were (μαcos δ, μδ) = (−1.32 ± 0.15 mas yr−1, −2.86 ± 0.34 mas yr−1) and, respectively. The line-of-sight velocity of the water maser emission is similar to that of the H91α recombination line emission detected at the Sgr D Hiiregion. The spatial position and line-of-sight velocity of the water maser emission indicate that this source is physically associated with the extended Hiisource seen under radio continuum observations. Thus, our results suggest that the Sgr D Hiiregion is located in the Scutum arm of the Galactic disk. We discuss this new view of the Sgr D complex, based on the parallax and proper motions.