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No provision is made to estimate the sensitivity of a mosaic in frequency cycling mode. This is to avoid mixing the complexity of both modes...
This section is split into two parts. We first describe the fast area-based estimate used when only the requested map area is known, as in the online sensitivity estimator. We then describe the refined pointing-list estimate used when the actual mosaic setup is known, as in the Proposal Management System. The two estimates share the same radiometer equation and observing-overhead model, but they differ in how the mosaic geometry is represented: the first uses an equivalent number of primary beams, while the second uses the actual pointing offsets to estimate the typical sensitivity and its variation across the imaged area. The second one is more accurate and it is needed to get the correct answer in dual band to take into account under or over-sampling in the band that is not used to define the pointing offsets of the mosaic.