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arXiv · 2302.08147

VGOS VLBI Intensives between MACGO12M and WETTZ13S for the rapid determination of UT1-UTC

Matthias Schartner·Leonid Petrov·Christian Plötz·Frank G. Lemoine·Eusebio Terrazas·Benedikt Soja
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Abstract

In this work, we present a status update and results of the designated research and development VLBI Intensive program VGOS-INT-S, observed between MACGO12M and WETTZ13S for the rapid determination of the Earth's phase of rotation, expressed via UT1-UTC. The main novelty of these sessions is the use of a special observation strategy, rapidly alternating between high- and low-elevation scans, enabling an improved determination of delays caused by the neutral atmosphere. Since 2021, 25 Intensive sessions have been observed successfully. In early 2022, VGOS-INT-S was among the most accurate Intensive programs with an average formal error $\sigma_{UT1-UTC}$ of 3.1 $\mu$s and a bias w.r.t. IERS C04 of 1.1 $\mu$s. Later, the session performance decreased due to multiple technical difficulties.

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Matthias Schartner, Leonid Petrov, Christian Plötz, Frank G. Lemoine, Eusebio Terrazas, Benedikt Soja. 2023-02-16. VGOS VLBI Intensives between MACGO12M and WETTZ13S for the rapid determination of UT1-UTC. https://doi.org/10.1007/1345_2023_222

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