Journal Article

First Results from the JWST Early Release Science Program Q3D: Ionization Cone, Clumpy Star Formation, and Shocks in a z = 3 Extremely Red Quasar Host

Mainieri, Vincenzo, Johnson, Sean D, Lutz, Dieter, Nesvadba, Nicole P. H, Chen, Hsiao-Wen, Ogle, Patrick, Zakamska, Nadia L, Ishikawa, Yuzo, Lützgendorf, Nora, Bertemes, Caroline, Murphree, Grey, Hamann, Fred, Wylezalek, Dominika, Diachenko, Nadiia, Veilleux, Sylvain, Sankar, Swetha, Grace Lim, Hui Xian, Vayner, Andrey, Heckman, Timothy, Barrera-Ballesteros, Jorge K, Liu, Weizhe, Hainline, Kevin N, McCrory, Ryan, Greene, Jenny E, Whitesell, Lillian, Sturm, Eckhard, Rupke, David S. N, Goulding, Andy D

2023

Overview

Massive galaxies formed most actively at redshifts z = 1–3 during the period known as “cosmic noon.” Here we present an emission-line study of the extremely red quasar SDSSJ165202.64+172852.3’s host galaxy at z = 2.94, based on observations with the Near Infrared Spectrograph integral field unit on board JWST. We use standard emission-line diagnostic ratios to map the sources of gas ionization across the host and a swarm of companion galaxies. The quasar dominates the photoionization, but we also discover shock-excited regions orthogonal to the ionization cone and the quasar-driven outflow. These shocks could be merger-induced or—more likely, given the presence of a powerful galactic-scale quasar outflow—these are signatures of wide-angle outflows that can reach parts of the galaxy that are not directly illuminated by the quasar. Finally, the kinematically narrow emission associated with the host galaxy presents as a collection of 1 kpc–scale clumps forming stars at a rate of at least 200 M ⊙ yr−1. The interstellar medium within these clumps shows high electron densities, reaching up to 3000 cm−3, with metallicities ranging from half to a third solar with a positive metallicity gradient, and V-band extinctions up to 3 mag. The star formation conditions are far more extreme in these regions than in local star-forming galaxies but consistent with those of massive galaxies at cosmic noon. The JWST observations simultaneously reveal an archetypal rapidly forming massive galaxy undergoing a merger, a clumpy starburst, an episode of obscured near-Eddington quasar activity, and an extremely powerful quasar outflow.

• Publisher: IOP Publishing
• Subject: Clumps / Electron density / Emission / Emission standards / Galaxies / Gas ionization / Interstellar matter / Interstellar medium / Ionization / Metallicity / Near infrared radiation / Outflow / Photoionization / Quasars / Star & galaxy formation / Star formation / Stars / Stars & galaxies