Directly Tracing Cool Filamentary Accretion over >100 kpc into the Interstellar Medium of a Quasar Host at z = 1

Abstract

We report the discovery of giant (50−100 kpc) [O ii] emitting nebulae with MUSE in the field of TXS 0206−048, a luminous quasar at z = 1.13. “Down-the-barrel” UV spectra of the quasar show absorption at velocities coincident with those of the extended nebulae, enabling new insights into inflows and outflows around the quasar host. One nebula exhibits a filamentary morphology extending over 120 kpc from the halo toward the quasar and intersecting with another nebula surrounding the quasar host with a radius of 50 kpc. This is the longest cool filament observed to date and arises at higher redshift and in a less massive system than those in cool-core clusters. The filamentary nebula has line-of-sight velocities >300 km s−1 from nearby galaxies but matches that of the nebula surrounding the quasar host where they intersect, consistent with accretion of cool intergalactic or circumgalactic medium or cooling hot halo gas. The kinematics of the nebulae surrounding the quasar host are unusual and complex, with redshifted and blueshifted spiral-like structures. The emission velocities at 5−10 kpc from the quasar match those of inflowing absorbing gas observed in UV spectra of the quasar. Together, the extended nebulae and associated redshifted absorption represent a compelling case of cool, filamentary gas accretion from halo scales into the extended interstellar medium and toward the nucleus of a massive quasar host. The inflow rate implied by the combined emission and absorption constraints is well below levels required to sustain the quasar’s radiative luminosity, suggesting anisotropic or variable accretion.

An Ensemble Study of Turbulence in Extended QSO Nebulae at z ≈ 0.5–1

“…In addition, turbulence in the CGM can also be produced by Kelvin-Helmholtz instability during the accretion of cool gas streams (e.g., Mandelker et al 2019;Vossberg et al 2019;Li et al 2023), and the motions of fragmented cool gas clumps in disrupted, turbulent mixing zones near the accreting streams are predicted to be subsonic in numerical simulations (e.g., Aung et al 2019). Among our sample, the nebula in the field of TXS0206−048 exhibits compelling signs of cool, filamentary gas accretion from large scales (Johnson et al 2022), suggesting that the observed subsonic turbulence may be in part produced through the accreting streams.…”

“…Based on the velocity dispersion of member galaxies in the QSO host group environment, the halo mass of the QSO hosts in our sample is estimated to be ≈10 13 -10 14 M e (see, e.g., Johnson et al 2018Johnson et al , 2022Helton et al 2021;Liu et al 2024). This mass range suggests a viral temperature of T ≈ 10 6 -10 7 K for the underlying hot halo (e.g., Mo et al 2010).…”

Metal line emission from galaxy haloes at z~1

“…Detailed analysis of the kinematics and physical properties of the extended gas and galaxies are required to establish whether the [O ] emission originates from gas stripping, outflows or combination of both. Furthermore, there have been detections of extended nebulae (≈ 10 − 120 kpc) in [O ], H 𝛽 and [O ] emission from galaxy groups hosting quasars at 𝑧 ≈ 0.5−1 (Johnson et al 2018(Johnson et al , 2022Helton et al 2021). These observations suggest gas stripping from the interstellar medium of interacting galaxies, and cool, filamentary gas accretion as possible origins of the extended gaseous structures.…”

“…The metal-enriched halo gas has been more challenging to detect (Rickards Vaught et al 2019), as expected from theoretical grounds due to their lower SB (Bertone & Schaye 2012;Frank et al 2012;Piacitelli et al 2022). This technique has nevertheless seen many recent successes, such as the detection of extended nebulae in [O ] and [O ] emission around quasars (Johnson et al 2018(Johnson et al , 2022Helton et al 2021), galaxy groups and clusters (Epinat et al 2018;Boselli et al 2019;Chen et al 2019), and ultraluminous galaxies (Rupke et al 2019) at 𝑧 < 1. Furthermore, extended Mg emission has been detected around a few galaxies at 𝑧 < 2 using long-slit spectroscopy (Rubin et al 2011;Martin et al 2013) and IFU observations (Rupke et al 2019;Burchett et al 2021;Zabl et al 2021;Shaban et al 2022).…”

Observational Evidence of the Prevalence of Bipolar Galactic Outflows out to 10 kpc at z ≈ 1 for Massive Galaxies

“…During the past ten years, integral field spectrograph (IFS) facilities such as VLT/MUSE [5] and Keck/KCWI [6] have enabled mapping the CGM or even the IGM in emission using several tracers such as Lyα [7][8][9][10][11][12], C IV, He II and C III] [13], and other rest-frame optical emission lines [14,15] out to very large distances from galaxies. Yet Lyα emission can only be observed by ground-based facilities at z ≳ 2, and due to the severe effects of cosmological surface brightness dimming it is very difficult to obtain spatially resolved spectroscopy at such high redshifts.…”