Gas and galaxies in filament between clusters of galaxies: The study of A399-A401

Understand

We have performed a multi-wavelength analysis of two galaxy cluster systems selected with the thermal Sunyaev-Zel'dovich (tSZ) effect and composed of cluster pairs and an inter-cluster filament.

• We have focused on one pair of particular interest: A399-A401 at redshift z~0.073 seperated by 3 Mpc.
• We have also performed the first analysis of one lower significance newly associated pair: A21-PSZ2 G114.09-34.34 at z~0.094, separated by 4.2 Mpc.
• We have characterised the intra-cluster gas using the tSZ signal from Planck and, when this was possible, the galaxy optical and infra-red (IR) properties based on two photometric redshift catalogs: 2MPZ and WISExSCOS.