Measuring the cosmic radio dipole with MeerKAT

by Jonah Wagenveld

Tuesday Jul 23, 2024, 2:15 PM → 3:45 PM Europe/Berlin

D6-135 (UHG)

The cosmic radio dipole is an anisotropy in the number counts of radio
sources with respect to the cosmic background. Results have shown a tension between the radio dipole and the dipole as measured from the cosmic microwave background (CMB), presenting an intriguing puzzle as to the cause of this discrepancy. We aim to measure the dipole with the MeerKAT Absorption Line Survey (MALS) data release 2, a catalogue containing nearly a million sources observed in 391 pointings at L-band. We present the characterisation of completeness and noise properties of the catalogue, as well as novel dipole estimators developed for this measurement. We discuss the challenges that came along with a measurement of the dipole on MALS in the form of some persistent systematics. We discuss some of these systematic effects present in the MeerKAT data and their possible causes, and how these could be addressed for MALS and other surveys that aim to do large scale
cosmology. 

2024-07-23_JonahWagenveld.pdf