In recent years, many studies have reported substantial populations of large galaxies with
low surface brightness in local galaxy clusters. Various theories that aim to explain the
presence of such ultra-diffuse galaxies (UDGs) have since been proposed. A key question
that will help to distinguish between models is whether UDGs have counterparts in host
haloes with lower masses, and if so, what their abundance as a function of halo mass is. We
here extend our previous study of UDGs in galaxy clusters to galaxy groups. We measure …

In recent years, many studies have reported substantial populations of large galaxies with
low surface brightness in local galaxy clusters. Various theories that aim to explain the
presence of such ultra-diffuse galaxies (UDGs) have since been proposed. A key question
that will help to distinguish between models is whether UDGs have counterparts in host
haloes with lower masses, and if so, what their abundance as a function of halo mass is. We
here extend our previous study of UDGs in galaxy clusters to galaxy groups. We measure …