论文标题
短基线干涉法在Onsala空间天文台的本地领带实验
Short-baseline interferometry local-tie experiments at the Onsala Space Observatory
论文作者
论文摘要
我们从Onsala空间天文台的三个大地基线干涉仪（VLBI）站之间进行了观察，相关性和分析，对三种大量基线干涉仪（VLBI）站之间的干涉测量值进行了结果。在2019年和2020年总共观察到25个会话，其中大多数长24小时，仅使用X波段。这些涉及传统VLBI站Onsala60和Onsala双望远镜，Onsa13ne和Onsa13SW，这是下一代Geodetic Vlbi Global Global观察系统（VGOS）的两个宽带站。我们使用了两个分析包：Nusolve来预处理数据和解决歧义，以及ASCOT来解决站点位置，包括对射电望远镜的重力变形进行建模和其他重要效果。我们使用相位延迟获得了每个会话的加权根平方邮政邮政残差，并使用组延迟获得了10-15 ps的顺序。在VGOS站之间的基线（相当短）的基线实现了最佳性能。作为这项工作的主要结果，我们确定了VTRF2020B中Onsala双望远镜的坐标，其毫米精度。从现在开始，应将这组新的坐标用于调度，相关性，作为数据分析的先验以及与经典的本地系列技术进行比较。最后，我们发现相对于组延期，从相分段估算的位置是偏移$ \ sim+3 $ mm。 （依赖高程）效应的其他建模可能有助于对此偏移的未来理解。
We present results from observation, correlation and analysis of interferometric measurements between the three geodetic very long baseline interferometry (VLBI) stations at the Onsala Space Observatory. In total 25 sessions were observed in 2019 and 2020, most of them 24 hours long, all using X-band only. These involved the legacy VLBI station ONSALA60 and the Onsala twin telescopes, ONSA13NE and ONSA13SW, two broadband stations for the next generation geodetic VLBI global observing system (VGOS). We used two analysis packages: nuSolve to pre-process the data and solve ambiguities, and ASCOT to solve for station positions, including modelling gravitational deformation of the radio telescopes and other significant effects. We obtained weighted root mean square postfit residuals for each session on the order of 10-15 ps using group delays and 2-5 ps using phase delays. The best performance was achieved on the (rather short) baseline between the VGOS stations. As the main result of this work we determined the coordinates of the Onsala twin telescopes in VTRF2020b with sub-millimeter precision. This new set of coordinates should be used from now on for scheduling, correlation, as a~priori for data analyses, and for comparison with classical local-tie techniques. Finally, we find that positions estimated from phase-delays are offset $\sim+3$ mm in the Up-component with respect to group-delays. Additional modelling of (elevation-dependent) effects may contribute to future understanding of this offset.
