Removing Clock-Drift and Ionospheric Errors from the CHIME-KKO VLBI Delays

The Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst project (CHIME/FRB) and its three outrigger telescopes will form a Very Long Baseline Interferometry (VLBI) network, with the goal of localising many hundreds of one-off and repeating FRBs to sub-arcsecond precision. Phase calibration is essential for successful VLBI, and requires removing errors due to ionosphere, clock, and instrumental delays. For calibrating the VLBI network, we plan to employ pulsars and traditional steady radio sources spread over the entire sky as calibrators. The first CHIME/FRB Outrigger, k'niʔatn k'l‿stk'masqt (KKO), came online in June 2022 and has been in commissioning ever since. It has a 66-km line of sight distance to CHIME and can provide a localisation accuracy of 1 arcsecond along the direction of the baseline. As the pathfinder for the outriggers, KKO has enabled the development and testing of our VLBI calibration techniques.