The known variety of galaxy clusters is constantly increasing with our progress in understanding the severity of selection effects on observational samples and with obvious implications on cosmology and cluster physics.
In the talk, after a general introduction on galaxy clusters and a reminder on selection effects, I present perhaps the first X-ray unbiased sample of clusters with known masses and X-ray follow-up, its more variegate nature compared to clusters selected by the intracluster medium (X-ray or SZ), and first results based on a deeper X-ray follow-up of a few of them.
![Sterner, more universet, galakse](/astro/forskning/aktuelt/arrangementer/gjesteforelesninger-seminarer/fredagskollokvium/2021/images/ddb52e4c-9420-4871-acec-3392d7578aec.jpeg)
You can connect from 11:00 via
https://uio.zoom.us/j/64070681213?pwd=NndieWF5M0Y3RVZMN2Z3djAyS0JmUT09
Meeting ID: 640 7068 1213
Passcode: 864672
Attendees will be muted during the colloquium, but will have the
opportunity to ask questions at the end by clicking on the "raise hand”
button (or send a request to me via chat).