4 February: Marcin Glowacki

Speaker: Marcin Glowacki (University of Edinburgh)

Date: Wednesday 4 February 2026

Time: 15:00

Location: Physics 3.27

PATCHwork and MockKATS: Neutral hydrogen discoveries with MeerKAT and comparisons with samples using hydrodynamical simulations

The MeerKAT radio telescope in South Africa is one of the pathfinder instruments of the Square Kilometre Array (SKA). MeerKAT is currently the most sensitive radio interferometer for neutral hydrogen (HI) studies with the 21-cm line. While dedicated science surveys such as LADUMA and MIGHTEE-HI are well underway, several HI-rich groups have also been discovered from Open Time proposals. I will present an example of this through the 49ers, a serendipitous discovery of 49 new gas-rich galaxies in a MeerKAT observation. I will also highlight the hundreds more detections that have been revealed in other MeerKAT datasets since, including HI absorption and dark galaxy candidates.

Given the numbers of HI detections with SKA pathfinders, we are already able to replicate samples using hydrodynamical simulations and make comparisons with observational studies. I will present recent and ongoing results from the ASymba collaboration, and mock samples of the LADUMA and MIGHTEE-HI surveys with the Simba/Simba-C and COLIBRE suites through mock spectral-line cubes. These results, such as of gas asymmetry, the baryonic Tully-Fisher relation, and HI scaling relations which span several orders of magnitude, are promising.