Exploring Sub-Array Strategies for MeerKAT-VLBI
MeerKAT is a South African radio interferometer that will be the most sensitive in its class untilthe operation of the Square Kilometre Array mid-frequency array. Like SKA1-mid, MeerKAT’santennas are configured in a dense core (driven primarily by pulsar and HI science), as well asmore extended spiral arms to provide higher angular resolution imaging. The inclusion of theMeerKAT array into global VLBI networks would add significant sensitivity to existing VLBInetworks, especially at the longest baselines (>7000 km). Moreover, this will strengthen therole of the Hartebeesthoek Radio Astronomy Observatory (HartRAO) in VLBI arrays throughimproved long-baseline calibration. MeerKAT-VLBI will extend VLBI coverage in the south-ern hemisphere which will be expanded further by the upcoming African VLBI Network (AVN).MeerKAT’s ability to be split into several sub-arrays and simultaneously generate interferometricand tied-array data products provides the opportunity to further increase its high expected scien-tific output. This flexibility could be utilized for VLBI experiments where a subset of antennasmay commensally or independently participate with the AVN, EVN or Australian LBA. The sameis true of two or more independent, MeerKAT-only experiments. Through a suite of simulations ofthe tied-array and interferometric performance of MeerKAT sub-arrays, this contribution presentsinitial results from a project that will investigate optimal sub-arraying strategies for a range of po-tential MeerKAT-VLBI and MeerKAT projects. We aim to systematically explore the scientific,technical, and processing trade-offs of MeerKAT sub-array and commensal observations, whichis ultimately aimed at maximising the scientific utility of both MeerKAT and the VLBI networksit will participate in.