Recent observations have shown that Ultra-Diffuse Galaxies (UDGs, which have the luminosities of dwarfs but sizes of giant galaxies) are surprisingly abundant in clusters of galaxies. The origin of these galaxies remains unclear, since one would naively expect them to be easily disrupted by tidal interactions in the cluster environment. Several formation scenarios have been proposed for UDGs, but these make a wide range of different testable observational predictions. I'll summarise recent results in this field, focussing on two key observables that have the potential to differentiate between the proposed models, namely 1) a measurement of their (sub)halo masses using weak gravitational lensing, and 2) their abundance in lower-mass haloes using data from the GAMA and KiDS surveys. I'll discuss implications and future prospects to learn more about the properties and formation histories of these elusive galaxies.
Unless announced otherwise, the lunch talks start at 12:30 sharp. The approximate duration of the lunch talk is given above, and additional time will be given for questions and discussion following the presentation. Please make sure that you take ample time to pick up your lunch beforehand.
Information for Speakers and Hosts: Talks by internal speakers are limited to 20 minutes, with additional time for questions. Visiting speakers can have up to 30 minutes, with additional time for questions. Hosts are responsible for bringing the speaker to the correct room in ample time to set up laptops etc., and for ensuring the speaker also has time for lunch.
For questions and/or suggestions concerning the lunch talks, please contact Themiya Nanayakkara () or Alvaro Hacar ()).