A unified calibration framework for 21 cm cosmology

Calibration precision is currently a limiting systematic in 21 cm cosmology experiments. While there are innumerable calibration approaches, most can be categorized as either `sky-based,' relying on an extremely accurate model of astronomical foreground emission, or `redundant,' requiring precisely regular array with near-identical antenna response patterns. Both these classes inflexible to the realities interferometric measurement. In practice, errors model, position offsets, and beam inhomogeneities degrade performance contaminate cosmological signal. Here we show that sky-based redundant unified into highly general physically motivated framework based Bayesian statistical formalism. Our new includes sky special cases but additionally support relaxing rigid assumptions implicit those approaches. Furthermore, present novel techniques such for arrays no baselines, representing alternative method imaging MWA Phase I. These approaches could mitigate systematics reduce error, thereby improving measurements.