IAG-IASPEI 2017

Presentation information

Oral

IAG Symposia » G01. Reference frames

[G01-2] Celestial reference frame and VLBI

Wed. Aug 2, 2017 10:30 AM - 12:00 PM Room 502 (Kobe International Conference Center 5F, Room 502)

Chairs: Zuheir Altamimi (Institut National de l'Information Géographique et Forestière) , Geoffrey Blewitt (University of Nevada, Reno)

10:45 AM - 11:00 AM

[G01-2-02] Testing of special relativity with geodetic VLBI

Oleg Titov1, Hana Krasna2 (1.Geoscience Australia, Canberra, Australia, 2.TU Wien, Vienna, Austria)

The geodetic Very Long Baseline Interferometry (VLBI) measures the group delay observable in the barycentric reference frame. As the Earth is orbiting around the Solar System Barycentre with the velocity V of 30 km/s,the VLBI turns to be a handy tool to detect the subtle effects of the special relativity theory with a magnitude of (V/c)^2. The theoretical correction for the second order terms reaches up to 300 ps, and it is implemented in the geodetic VLBI group delay model. The total contribution of the second order terms splits to two effects - the contraction of the Earth scale in the plane perpendicular to the orbital velocity vector direction, and the displacement of the radio source apparent position. We are using the Robertson-Mansouri-Sexl (RMS) formalism to probe the Lorentz invariance. We analyse the geodetic VLBI data with two independent software packages (OCCAM and VieVS) and show that the parameters of the RMS model can be estimated with a high accuracy.