Spatial distribution of ultra-diffuse galaxies within large-scale structures

Understand

Taking advantage of the Sloan Digital Sky Survey Stripe82 data, we have explored the spatial distribution of ultra-diffuse galaxies (UDGs) within an area of 8$\times$8 Mpc$^2$ centred around the galaxy cluster Abell 168 ($z$ = 0.045).

• This intermediate massive cluster ($\sigma$ = 550 km s$^{-1}$) is surrounded by a complex large-scale structure.
• Our work confirms the presence of UDGs in the cluster and in the large-scale structure that surrounds it, and it is the first detection of UDGs outside clusters.
• Approximately 50 per cent of the UDGs analysed in the selected area inhabit the cluster region ($\sim$11 $\pm$ 5 per cent in the core and $\sim$39 $\pm$ 9 per cent in the outskirts), whereas the remaining UDGs are found outside the main cluster structure ($\sim$50 $\pm$ 11 per cent).