Speaker
Description
The low-mass end of the HI mass function (HIMF) is thought to be a sensitive probe of environment-driven galaxy evolution. The general expectation is that, at low MHI, the HIMF becomes flatter as the environment density increases because of the removal of HI from small galaxies. The main challenge to measure this effect reliably is to have enough HI detections and/or go sufficiently deep in MHI. The MeerKAT Fornax Survey detects HI in the Fornax cluster down to below 1e+6 Msun, and thus provides a good sample for this type of work. We find that the Fornax galaxy HIMF follows a Schechter function comparable to that of the field down to MHI ~ 1e+7 Msun, and collapses abruptly below this value. The collapse occurs at SNR ~ 20, which makes us confident that it is not caused by the incompleteness of the HI catalogue. I will discuss our result in the context of previous studies which, using more complex techniques on shallower data, also suggest that the HIMF may collapse at some low MHI value in clusters.
| Topics | Galaxy Evolution & AGN |
|---|
