The cold circumgalactic medium in emission: MgII halos in TNG50

Abstract

We outline theoretical predictions for extended emission from MgII, tracing cool ~10^4 K gas in the circumgalactic medium (CGM) of star-forming galaxies in the high-resolution TNG50 cosmological magnetohydrodynamical simulation. We synthesize surface brightness maps of this strong rest-frame ultraviolet metal emission doublet (2796, 2803), adopting the assumption that the resonant scattering of MgII can be neglected and connecting to recent and upcoming observations with the Keck/KCWI, VLT/MUSE, and BlueMUSE optical integral field unit spectrographs. Studying galaxies with stellar masses 7.5 < log(M*/M_sun) < 11 at redshifts z=0.3, 0.7, 1 and 2 we find that extended MgII halos in emission, similar to their Lyman-alpha counterparts, are ubiquitous across the galaxy population. Median surface brightness profiles exceed 10^-19 erg/s/cm^2/arcsec^2 in the central ~10s of kpc, and total halo MgII luminosity increases with mass for star-forming galaxies, reaching 10^40 erg/s for M* ~ 10^9.5 Msun. MgII halo sizes increase from a few kpc to > 20 kpc at the highest masses, and sizes are larger for halos in denser environments. MgII halos are highly structured, clumpy, and asymmetric, with isophotal axis ratio increasing with galaxy mass. Similarly, the amount and distribution of MgII emission depends on the star formation activity of the central galaxy. Kinematically, inflowing versus outflowing gas dominates the MgII luminosity at high and low galaxy masses, respectively, although the majority of MgII halo emission at z~0.7 traces near-equilibrium fountain flows and gas with non-negligible rotational support, rather than rapidly outflowing galactic winds.

MNRAS 2021, comments welcome

References in corpus (36)

• Simulating galaxy formation with black hole driven thermal and kinetic feedback
• The Circumgalactic Medium
• The effect of photo-ionization on the cooling rates of enriched, astrophysical plasmas
• A New Calculation of the Ionizing Background Spectrum and the Effects of HeII Reionization
• Ubiquitous outflows in DEEP2 spectra of star-forming galaxies at z=1.4
• The MUSE Hubble Ultra Deep Field Survey: I. Survey description, data reduction and source detection
• The Cosmic Baryon and Metal Cycles
• Accretion of gas onto nearby spiral galaxies
• Detection of large-scale X-ray bubbles in the Milky Way halo
• Resolving small-scale cold circumgalactic gas in TNG50
• The ALPINE-ALMA [CII] survey: Star-formation-driven outflows and circumgalactic enrichment in the early Universe
• Unifying X-ray Scaling Relations from Galaxies to Clusters
• New perspectives on strong z=0.5 MgII absorbers: are halo-mass and equivalent width anti-correlated?
• Damped Lyman-alpha absorbers as a probe of stellar feedback
• Evolution of the Cool Gas in the Circumgalactic Medium (CGM) of Massive Halos -- A Keck Cosmic Web Imager (KCWI) Survey of Ly$\alpha$ Emission around QSOs at $z\approx 2$
• The large and small scale properties of the intergalactic gas in the Slug Ly-alpha nebula revealed by MUSE HeII emission observations
• The REQUIEM Survey I: A Search for Extended Ly-Alpha Nebular Emission Around 31 z>5.7 Quasars
• A 100-kiloparsec wind feeding the circumgalactic medium of a massive compact galaxy
• Probing Cosmic Dawn with Emission Lines: Predicting Infrared and Nebular Line Emission for ALMA and JWST
• Optically-Thin Spatially-Resolved Mg II Emission Maps the Escape of Ionizing Photons
• Kinematics of Circumgalactic Gas: Feeding Galaxies and Feedback
• A clumpy and anisotropic galaxy halo at z=1 from gravitational-arc tomography
• Dust-depletion sequences in damped Lyman-α absorbers: a unified picture from low-metallicity systems to the Galaxy
• The MUSE Extremely Deep Field: the Cosmic Web in Emission at High Redshift
• The properties of the cool circumgalactic gas probed with the SDSS, WISE and GALEX surveys
• The Circum-Galactic Medium of MASsive Spirals II: Probing the Nature of Hot Gaseous Halo around the Most Massive Isolated Spiral Galaxies
• The MUSE Hubble Ultra Deep Field Survey VIII : Extended Lyman-alpha haloes around high-redshift star-forming galaxies
• MusE GAs FLOw and Wind (MEGAFLOW) VIII. Discovery of a MgII emission halo probed by a quasar sightline
• Characterizing the abundance, properties, and kinematics of the cool circumgalactic medium of galaxies in absorption with SDSS DR16
• The Production of Cold Gas Within Galaxy Outflows
• Empirically Constrained Predictions for Metal-Line Emission from the Circumgalactic Medium
• The MUSE Hubble Ultra Deep Field Survey: VII. FeII* Emission in Star-Forming Galaxies
• A Graphical Interpretation of Circumgalactic Precipitation
• On the detectability of visible-wavelength line emission from the local circumgalactic and intergalactic medium
• Most of the cool CGM of star-forming galaxies is not produced by supernova feedback
• A VLT/FORS2 Narrowband Imaging Search for MgII Emission Around z ~ 0.7 Galaxies

Cited by in corpus (29)

• The Structure of Multiphase Galactic Winds
• Metal-enriched halo gas across galaxy overdensities over the last 10 billion years
• MUSE Analysis of Gas around Galaxies (MAGG) -- IV: The gaseous environment of $z\sim$ 3-4 Lyman-alpha emitting galaxies
• Predictions for anisotropic X-ray signatures in the circumgalactic medium: imprints of supermassive black hole driven outflows
• MgII in the JWST Era: a Probe of Lyman Continuum Escape?
• The MUSE eXtremely Deep Field: Individual detections of Lyα haloes around rest-frame UV-selected galaxies at z~2.9-4.4
• Metal line emission from galaxy haloes at z~1
• X-ray metal line emission from the hot circumgalactic medium: probing the effects of supermassive black hole feedback
• Cool circumgalactic gas in galaxy clusters: connecting the DESI legacy imaging survey and SDSS DR16 MgII absorbers
• High resolution modeling of [CII], [CI], [OIII] and CO line emission from the ISM and CGM of a star forming galaxy at z ~ 6.5
• MUSE-ALMA Haloes VII: Survey Science Goals & Design, Data Processing and Final Catalogues
• The cosmic web in Lyman-alpha emission
• Kinematics, Structure, and Mass Outflow Rates of Extreme Starburst Galactic Outflows
• Cooling flows around cold clouds in the circumgalactic medium: steady-state models & comparison with TNG50
• Resonant scattering of the OVII X-ray emission line in the circumgalactic medium of TNG50 galaxies
• A 30 kpc Spatially Extended Clumpy and Asymmetric Galactic Outflow at z $\sim$ 1.7
• Linking Mg II and [O II] spatial distribution to ionizing photon escape in confirmed LyC leakers and non-leakers
• The effects of local stellar radiation and dust depletion on non-equilibrium interstellar chemistry
• The Anisotropic Circumgalactic Medium of Massive Early-Type Galaxies
• Metal content of the circumgalactic medium around star-forming galaxies at z $\sim$ 2.6 as revealed by the VIMOS Ultra-Deep Survey
• The cooler past of the intracluster medium in TNG-Cluster
• The environments and hosts of metal absorption at z>5
• Absorption-based Circumgalactic Medium Line Emission Estimates
• Distinguishing Between Photoionized and Collisionally Ionized Gas in the Circumgalactic Medium
• Simulated [CII] in high-z galaxies
• A public grid of radiative transfer simulations for Lyman-alpha and metal lines in idealised galactic outflows
• MUSE Analysis of Gas around Galaxies (MAGG) -- VI. The cool and enriched gas environment of z$\gtrsim$3 Ly$\alpha$ emitters
• H$\alpha$ emission in the outskirts of galaxies at z=0.4
• First statistical constraints on galactic scale outflows properties traced by their extended Mg II emission with MUSE