Speaker
Description
Observations from MeerKLASS exhibit significantly higher chromaticity than standard simulations, requiring approximately much more PCA modes for effective foreground removal than the 4–5 modes typically predicted. To address this discrepancy, we present a Bayesian framework designed to measure and characterize chromatic modulating effects on intensity maps. Our model represents instrumental and environmental effects as a product or convolution of a modulation kernel with the underlying sky signal. By assuming a power-law frequency dependence for the synchrotron sky, while marginalizing over model uncertainties, we simultaneously infer the modulation kernel and its associated statistical uncertainties. We validate this method using simulations that incorporate realistic beam chromaticity and sidelobes. In this talk, I will present preliminary results from this proof-of-concept work, demonstrating the method’s potential for characterize systematics