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

Paper in 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.