High dynamic range wide field imaging method in radio interferometry

Radio astronomy has provided unique and plentiful information about our universe. Wide--field continuum radio surveys have made vital contributions to our understanding of the formation and evolution of galaxies, clusters and AGNs (active galactic nuclei) over cosmic time. Using upgraded and proposed radio interferometers, increasingly wide and sensitive radio continuum surveys are planned, or being conducted, which require wide-field imaging methods to produce wide-survey images. In the past the dynamic range of images produced by existing methods is limited, and has often failed to achieve the dynamic range objective of the survey. To deal with this problem, a high dynamic range wide-field imaging method for radio interferometers is proposed. This method improves the widely-used W-stacking method, enabling radio astronomers to produce high--fidelity wide-field interferometric images with a dynamic range (peak:rms) exceeding 10^6:1. This method has been implemented in WSCLEAN and NIFTY by their respective authors.