论文标题
逆多览II:南半球的微弧度三角差异6.7〜GHz甲醇masers G232.62+00.99和G323.74 $ 00.26
Inverse MultiView II: Microarcsecond Trigonometric Parallaxes for Southern Hemisphere 6.7~GHz Methanol Masers G232.62+00.99 and G323.74$-$00.26
论文作者
论文摘要
我们介绍了南半球视差视差干涉射线射线射击传统调查(\ Spirals):$10μ$ AS-AS-CRACCRATE视差和适当的动作,用于两种使用逆多维图校准方法获得的南半球6.7 GHz甲醇masers。使用澳大利亚和新西兰的一系列射电望远镜,我们测量了与星形区域G232.62+00.99相关的三角差异和适当的动作, $μ_y= 2.249 \ pm0.049 $ 〜mas〜y $^{ - 1} $,这意味着其距离为$ d = 1.637 \ pm0.029 $ 〜kpc。这些测量值代表了通过非常长的基线阵列观测值对与该区域相关的12 〜GHz甲醇masers的长期基线阵列观察获得的先前测量值的提高超过3倍。我们还测量了G323.74-- 00.26的三角视差和适当的运动为$π= 0.364 \ pm0.009 $ 〜MAS,$μ_x= -3.239 \ pM0.025 $ 〜mas〜mas〜mas〜mas〜y $ $ $ $ $ $^y $^{ - 1} $ d = 2.747 \ pm0.068 $ 〜kpc的距离。这些是迄今为止为6.7〜GHz II类甲醇酶获得的三角差异的最准确测量。我们确认G232.62+00.99位于本地臂中,发现G323.74--00.26在象征库中。我们还研究了两个masers的结构和内部动力学。
We present the first results from the Southern Hemisphere Parallax Interferometric Radio Astrometry Legacy Survey (\spirals): $10μ$as-accurate parallaxes and proper motions for two southern hemisphere 6.7 GHz methanol masers obtained using the inverse MultiView calibration method. Using an array of radio telescopes in Australia and New Zealand, we measured the trigonometric parallax and proper motions for the masers associated with the star formation region G232.62+00.99 of $π= 0.610\pm0.011$~mas, $μ_x=-2.266\pm0.021$~mas~y$^{-1}$ and $μ_y=2.249\pm0.049$~mas~y$^{-1}$, which implies its distance to be $d=1.637\pm0.029$~kpc. These measurements represent an improvement in accuracy by more than a factor of 3 over the previous measurements obtained through Very Long Baseline Array observations of the 12~GHz methanol masers associated with this region. We also measure the trigonometric parallax and proper motion for G323.74--00.26 as $π= 0.364\pm0.009$~mas, $μ_x=-3.239\pm0.025$~mas~y$^{-1}$ and $μ_y=-3.976\pm0.039$~mas~y$^{-1}$, which implies a distance of $d=2.747\pm0.068$~kpc. These are the most accurate measurements of trigonometric parallax obtained for 6.7~GHz class II methanol masers to date. We confirm that G232.62+00.99 is in the Local arm and find that G323.74--00.26 is in the Scutum-Centaurus arm. We also investigate the structure and internal dynamics of both masers.