Source Structure in VGOS Fringe-Fitting (SOFT)
Wider research context: Very Long Baseline Interferometry (VLBI) is a backbone of modern global reference frame and Earth orientation investigations. To provide the accuracy needed for contemporary studies in geo-modelling and geo-hazard investigations, the International VLBI Service for Geodesy and Astrometry (IVS) is pushing for a quantum leap with the establishment of its VLBI Global Observing System (VGOS). With project SOFT, we provide a research element to VGOS, which is essential for significantly improving the accuracy of the VLBI group delay observables and, thus, of the overall VLBI results. We propose a novel data processing technique to correct for one of the dominant remaining systematic errors, the effect of the structure of radio source emission.