Publication Date:
2018-06-06
Description:
GPS TEC ionosphere maps were first applied to a series of K and Q band VLBA astrometry sessions to try to eliminate a declination bias in estimated source positions. Their usage has been expanded to calibrate X-band only VLBI observations as well. At K-band, approx.60% of the declination bias appears to be removed with the application of GPS ionosphere calibrations. At X-band however, it appears that up to 90% or more of the declination bias is removed, with a corresponding increase in RA and declination uncertainties of approx.0.5 mas. GPS ionosphere calibrations may be very useful for improving the estimated positions of the X-only and S-only sources in the VCS and RDV sessions.
Keywords:
Geophysics
Type:
Proceedings of the Sixth General Meeting of the International VLBI Service for Geodesy and Astrometry; 242-246; NASA/CP-2010-215864
Format:
application/pdf
