Atmospheric parameters derived from VGOS sessions observed with the Onsala twin telescopes

Paper i proceeding, 2023

We compare the atmospheric parameters derived from the analysis of VGOS sessions that were observed with the Onsala twin telescopes to the corresponding results derived from co-located GNSS stations and a ground-based microwave radiometer at Onsala. The focus is on the first four VGOS Research & Development sessions, observed in 2021 and 2022, aimed at testing scheduling strategies with short scan length in order to obtain a good local sky coverage. The data analysis of all three techniques allows a high temporal resolution of 5 min for the atmospheric parameters. We find high correlation (0.97) for the zenith total delays of the three techniques, and pair-wise weighted root mean square difference on the order of 4–10 mm. The linear horizontal delay gradients are less well correlated (0.4–0.5) and have pair-wise weighted root mean square differences in the sub-mm range.