Speaker
Description
Following the cosmological principle, the observed dipole anisotropy of the cosmic microwave background (CMB), which is presumably due to the motion of the solar system, should also be detectable in the distribution of visible matter. This study uses a new Bayesian estimator to measure the cosmic radio dipole in several wide-field radio surveys, including the NVSS, VLASS and RACS-low catalogues, as well as, for the first time, the LoTSS-DR2 and RACS-mid radio source catalogues. The estimator provides a more accurate description of the observations by accounting for multi-component radio sources. For the measurement, the radio dipole direction remains fixed to the CMB dipole direction. This study finds amplitudes that are in line with the CMB dipole expectation. However, it cannot be ruled out that there is an excess radio dipole.
