# Overdensities of SMGs around WISE-selected, ultra-luminous, high-redshift AGN

## TL;DR

This study reveals that WISE-selected hot dust obscured galaxies and radio-selected AGNs at high redshift are surrounded by overdensities of dusty, star-forming galaxies, indicating potential protocluster environments and providing insights into galaxy clustering.

## Contribution

It demonstrates that these high-redshift AGN environments are overdense in SMGs and offers new evidence on their clustering properties and potential as protocluster signposts.

## Key findings

- Overdensities of SMGs around Hot DOGs and WISE/radio AGNs are higher than in typical fields.
- Mid-IR colors of companion sources are consistent with SMGs.
- No angular correlation detected on the scales studied, suggesting larger-scale clustering.

## Abstract

We investigate extremely luminous dusty galaxies in the environments around WISE-selected hot dust obscured galaxies (Hot DOGs) and WISE/radio-selected active galactic nuclei (AGNs) at average redshifts of z = 2.7 and z = 1.7, respectively. Previous observations have detected overdensities of companion submillimetre-selected sources around 10 Hot DOGs and 30 WISE/radio AGNs, with overdensities of ~ 2 - 3 and ~ 5 - 6 , respectively. We find that the space densities in both samples to be overdense compared to normal star-forming galaxies and submillimetre galaxies (SMGs) in the SCUBA-2 Cosmology Legacy Survey (S2CLS). Both samples of companion sources have consistent mid-IR colours and mid-IR to submm ratios as SMGs. The brighter population around WISE/radio AGNs could be responsible for the higher overdensity reported. We also find the star formation rate density (SFRDs) are higher than the field, but consistent with clusters of dusty galaxies. WISE-selected AGNs appear to be good signposts for protoclusters at high redshift on arcmin scales. The results reported here provide an upper limit to the strength of angular clustering using the two-point correlation function. Monte Carlo simulations show no angular correlation, which could indicate protoclusters on scales larger than the SCUBA-2 1.5arcmin scale maps.