Speaker
Description
Over a combination of large areas as well as smaller, deep fields observations, the LOFAR Two-metre sky survey (LoTSS, Tasse+ 2021, Sabater+ 2021, Shimwell+ 2022) is producing detailed knowledge of sources at low radio frequencies (144 MHz), across large periods of cosmic time. The combined area of these surveys as well as their depth and ancillary information provides exciting opportunities for cosmological analyses to learn about large-scale structure and the cosmological parameters underpinning our Universe, as inferred from the radio skies. For example, what can we learn about how galaxies trace dark matter, the cosmic radio dipole and what are the inferred values of cosmological parameters.
This talk, given on behalf of the LOFAR surveys cosmology team, will detail the cosmological understanding which we have learnt from the ~5,000 sq. deg of the wide area LoTSS-DR2 data release (Shimwell+ 2022). I will provide details of the observations employed and a discussion of the methods used to account for systematics across the large field of view of the survey from factors such as incompleteness and source smearing. I will present the results from a combination of analyses from the LOFAR surveys cosmology team, including looking at the:
Counts-in-Cell statistics (Pashapour-Ahmadabadi, Böhme+, in prep.);
the cosmic radio dipole (Böhme+, in prep.);
angular clustering across the surveyed area (Hale+ 2023);
cross-correlation analysis with the cosmic microwave background (Nakoneczny+ 2023);
cross-correlation with the eBOSS survey (Zheng+, in prep.);
Combined cosmological analysis (Heneka+, in prep.)
I will then summarise the combined understanding we have gained from these investigations.
