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Published on: May 29, 2019
Measurement of the solar gravitational deflection of radio waves using geodetic very-long-baseline interferometry
S S Shapiro1, J L Davis, D E Lebach
1Department of Physics, Guilford College, Greensboro, North Carolina 27410, USA. sshapiro@guilford.edu
Abstract:
We used very-long-baseline interferometry (VLBI) to measure the deflection by the Sun of radio waves emanating from distant compact radio sources. This bending is characterized in the parametrized post-Newtonian formalism by gamma, which is unity in general relativity. Using a large geodetic VLBI data set, we obtained gamma=0.9998(3)+/-0.0004(5) (estimated standard error). We found no systematic biases from our analysis of subgroups of data.
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