Revealing the link between halo mass and radio jet activities in quasars

TL;DR

This study reveals a strong link between dark matter halo mass and radio jet activity in quasars, showing that more powerful jets are associated with richer cluster environments, independent of black hole mass.

Contribution

It demonstrates a direct correlation between halo mass and quasar jet power, highlighting environmental influence over black hole properties in jet production.

Findings

Quasars with higher jet fractions reside in more massive dark matter haloes.

The correlation between halo mass and jet activity is not driven by black hole mass or luminosity.

Powerful jets are linked to dense cluster environments with halo masses of 10^{13-14} h^{-1} M_sun.

Abstract

There is a fundamental lack of understanding as to why quasars that are otherwise very similar can have such a wide range of radio jet powers, and the large-scale environment is thought to play an important role. We investigate the spatial clustering properties of 225,382 quasars from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) within the LOFAR Two-metre Sky Survey (LoTSS) Data Release 2 footprint, split by the statistically-calculated fraction of their radio flux densities contributed by jets (relative to the contribution from star formation). We find a positive correlation between the clustering strengths of quasars and their jet fraction, where quasars with a higher jet fraction have a higher clustering amplitude measured by their two-point correlation functions. We show that this correlation is unlikely related to differences in BH masses or bolometric luminosities. Quasars dominated by powerful jet activities generally reside in dark matter haloes $10-100$ times more massive than those without strong jets, with typical halo masses of $10^{13-14}\ h^{-1}M_\odot$, establishing a robust link between powerful AGN jets and rich cluster environments. Our results demonstrate that halo mass is important for determining the power of radio jets, but suggest that there is no minimum dark matter halo mass or BH mass required for the triggering of jets. The observed correlation suggests that BH spin is likely to play a minor role in jet production; instead, the key driver could be the presence of a strong magnetic flux.