- Home
- Scientific program
- Proceedings
- List of participants
- Photos
- Venue/Lodging
- Links
- Contact

Aletha de Witt
Type of contribution: poster

A Celestial Reference Frame at 22 GHz (K-band)

Aletha de Witt, Hartebeesthoek Radio Astronomy Observatory. Alessandra Bertarini, Max Planck Institut fu ̈r Radioastronomie. Chris Jacobs, Jet Propulsion Laboratory, California Institute of Technology/NASA. Jonathan Quick, Hartebeesthoek Radio Astronomy Observatory. Shinji Horiuchi, C.S.I.R.O/Canberra Deep Space Communications Complex. Jim Lovell, University of Tasmania Jamie McCallum, University of Tasmania Taehyun Jung, Korea Astronomy & Space Science Institute. Geraldine Bourda, University of Bordeaux. Patrick Charlot, University of Bordeaux.

Relative to observations at the standard S/X observing bands, at higher radio frequencies sources that make up the international celestial reference frame are expected to exhibit more compact source morphology and the effect of core-shift is expected to be smaller. This reduction in astrophysical systematics should allow for a more well-defined and stable reference frame at higher frequencies, and also be advantageous in tying the VLBI reference frame to future optical reference frames such as Gaia. Astrometric and imaging observations by Lanyi et al. (2010) and Charlot et al. (2010), provided a foundation for the development of a reference frame at 22 GHz (K-band). However, the current K-band frame consists of only 279 sources with weak coverage in the southern hemisphere and several localised regions with no sources, especially near the ecliptic and galactic planes. We present an overview of our plans to improve the accuracy and coverage of the K-band celestial reference frame and present ongoing results from our observational efforts. Specifically, dedicated high-resolution imaging and astrometric observations are currently underway to complete sky coverage in the south using South Africa to Australia baselines and to improve the K-band celestial reference frame in the North using the VLBA to densify the spatial coverage of sources. Our goal is to achieve a frame of at least 500 sources.