We present Lyα, He II and C IV observations of 7 redshift ~ 2 radio-loud quasars observed using the Keck Cosmic Web Imager (KCWI) and compare it to observed radio jet emission using archival VLA and ALMA radio observations. We detect 80-120 kpc diameter Lyα and 10-40 kpc He II and C IV emission around the targets. We find the Lyα emission to be brighter in the inner 30 kpc by factors of 2-10 compared to other literature samples. We reproduce the trend for increased total luminosity for a larger area on sky, but find our targets tend to be brighter for a given area when compared to literature observations, even when adjusting for the observational sensitivity. We infer that the He II and C IV is likely powered by quasar photoionization, with the ionizing radiation likely escaping along the radio jet axis which is aligned with the He II and C IV emission. The observations agree with a two component model of the CGM where the inner CGM (< 30 kpc) is directly influenced by the host galaxies, whereas the gas motion in the outer CGM (> 30 kpc) is influenced by gas turbulence and the larger environment around the host galaxies.
@article{arxiv.2603.22657,
title = {The Two Component Circumgalactic Medium Emission around z~2 Radio-loud Quasars},
author = {Sanchit Sabhlok and Shelley A. Wright and Andrey Vayner and Norman Murray and Lee Armus and Maren Cosens and James Wiley and Eileen Meyer and Karthik Reddy and Marie Wingyee Lau},
journal= {arXiv preprint arXiv:2603.22657},
year = {2026}
}