Speaker
Description
Neutral atomic hydrogen (HI) in galaxies is typically only directly detected out to a galactocentric radius imposed by the sensitivity of current radio observations, rather than the true physical extent of the HI disk. As a result, the low surface-brightness outskirts of HI disks - where environmental effects may be most pronounced - remain largely unexplored, despite being key to understanding how galaxies acquire and lose their gas. In this work, we use kinematic models derived for a low-redshift (z < 0.088) galaxy sample from the Looking at the Distant Universe with the MeerKAT Array (LADUMA) survey to guide HI stacking beyond the direct detection limit. By coherently stacking emission at large galactocentric radii, we can recover faint HI signals and constrain the gas distribution in the outermost regions of these galaxies, reaching column densities below those accessible through direct detections. These measurements will be used to investigate how HI properties, including column density and local linewidth, vary with radius, and whether they are influenced by environmental disturbances. This approach allows us to probe the physical processes shaping the outskirts of HI disks and assess the role of the environment in driving disk truncation.
| Apply for student award at which level: | PhD |
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| Consent on use of personal information: Abstract Submission | Yes, I ACCEPT |