A general Bayesian framework for foreground modelling and chromaticity correction for global 21 cm experiments

@article{Anstey2021AGB,
  title={A general Bayesian framework for foreground modelling and chromaticity correction for global 21 cm experiments},
  author={Dominic Anstey and Eloy de Lera Acedo and Will Handley},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2021}
}
The H i 21 cm absorption line is masked by bright foregrounds and systematic distortions that arise due to the chromaticity of the antenna used to make the observation coupling to the spectral inhomogeneity of these foregrounds. We demonstrate that these distortions are sufficient to conceal the 21 cm signal when the antenna is not perfectly achromatic and that simple corrections assuming a constant spatial distribution of foreground power are insufficient to overcome them. We then propose a… 

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