Talks and Poster Presentations (with Proceedings-Entry):
B. Soja, C. Jacobs, T. Runge, C. Naudet, R. Gross, A. de Witt, D. Gordon, J. Quick, J. McCallum, H. Krasna:
"Ionospheric calibration for K-band celestial reference frames";
Talk: 24th Meeting of the European VLBI Group for Geodesy and Astrometry,
Gran Canaria, Spain;
- 2019-03-19; in: "EVGA 2019 Abstract Book",
The International Celestial Reference Frame (ICRF) has traditionally been composed of radio source coordinates estimated from VLBI observations in S- and X-band. The ICRF3, released in 2018, included for the first time a CRF based on observations at K-band. A major benefit of observations at higher frequencies is that source structure effects are smaller. A disadvantage of the K-band data is that the single-frequency observations require external ionospheric calibrations. If the ionospheric corrections are of sufficient quality, a K-band CRF could have an astrometric accuracy better than the 20-30 μas source-structure-induced noise floor of current S/X-based CRFs.In the case of the ICRF3, the K-band observations were corrected using two-dimensional global ionospheric maps with a two-hour temporal resolution. In this study, we investigate the improvement in the K-band CRF when using calibrations based on ionospheric data with increased resolutions. In particular, we (1) test ionospheric products from JPL with a temporal resolution of 15 minutes and (2) evaluate a potential improvement in spatial resolution by assuming functioning GNSS equipment at all ten VLBA sites (currently, only five have GNSS stations that are contributing to ionospheric products).
Electronic version of the publication:
Created from the Publication Database of the Vienna University of Technology.