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arXiv · 1908.00973

Observations of radio sources near the Sun

Oleg Titov·Sebastien Lambert·Benedikt Soja·Fengchun Shu·Alexei Melnikov·Jamie McCallum·Lucia McCallum·Matthias Schartner·Aletha de Witt·Dmitrii Ivanov·Andrei Mikhailov·Sang Oh Yi·Wen Chen·Bo Xia·Masafumi Ishigaki·Sergei Gulyaev·Tim Natusch·Stuart Weston
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Abstract

Geodetic Very Long Baseline Interferometry (VLBI) data are capable of measuring the light deflection caused by the gravitational field of the Sun and large planets with high accuracy. The parameter $\gamma$ of the parametrized Post-Newtonian (PPN) formalism estimated using observations of reference radio sources near the Sun should be equal to unity in the general relativity. We have run several VLBI experiments tracking reference radio sources from 1 to 3 degrees from the Sun. The best formal accuracy of the parameter $\gamma$ achieved in the single-session mode is less than 0.01 percent, or better than the formal accuracy obtained with a global solution included all available observations at arbitrary elongation from the Sun. We are planning more experiments starting from 2020 using better observing conditions near the minimum of the Solar activity cycle.

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Oleg Titov, Sebastien Lambert, Benedikt Soja, Fengchun Shu, Alexei Melnikov, Jamie McCallum, Lucia McCallum, Matthias Schartner, Aletha de Witt, Dmitrii Ivanov, Andrei Mikhailov, Sang Oh Yi, Wen Chen, Bo Xia, Masafumi Ishigaki, Sergei Gulyaev, Tim Natusch, Stuart Weston. 2019-08-02. Observations of radio sources near the Sun. https://arxiv.org/abs/1908.00973

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