A high baryon fraction in massive haloes at z~3

Abstract

We investigate the baryon content of the circumgalactic medium (CGM) within the virial radius of $M_h\sim 10^{12}{M}_{\odot }$ haloes at z ~ 3, by modelling the surface brightness profile of the giant Ly$\alpha$ nebulae recently discovered by MUSE around bright QSOs at this redshift. We initially assume fluorescent emission from cold photo-ionized gas confined by the pressure of a hot halo. Acceptable CGM baryon fractions (equal or smaller than the cosmological value) require that the cold gas occupies $\lesssim$ 1% of the volume, but is about as massive as the hot gas. CGM baryon fractions as low as 30% of the cosmic value, as predicted by some strongly ejective feedback models at this redshift, are not easy to reconcile with observations, under our assumptions, unless both the QSO-hosting haloes at $z\sim 3$ are more massive than recent BOSS estimates based on clustering and the photo-ionized gas is colder than expected in a standard QSO ionizing radiation field. We also consider the option that the emission is dominated by photons scattered from the QSO broad line region. In this scenario, a very stringent lower limit to the baryon fraction can be obtained under the extreme assumption of optically thin scattering. We infer in this case a baryon fraction of at least 70% of the cosmic value, for fiducial parameters. Lower values require halo masses or gas temperatures different than expected, or that some mechanism keeps the cold gas systematically over-pressured with respect to the ambient medium.

Accepted for publication in MNRAS. 22 pages, 10 Figures

References in corpus (32)

• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• A Highly Consistent Framework for the Evolution of the Star-Forming "Main Sequence" from z~0-6
• Simulating galaxy formation with black hole driven thermal and kinetic feedback
• The effect of photo-ionization on the cooling rates of enriched, astrophysical plasmas
• A unified model for AGN feedback in cosmological simulations of structure formation
• The MUSE second-generation VLT instrument
• The COS-Halos Survey: Physical Conditions and Baryonic Mass in the Low-Redshift Circumgalactic Medium
• Mass, Metal, and Energy Feedback in Cosmological Simulations
• The 2013 Release of Cloudy
• Clustering of High Redshift ($z\ge 2.9$) Quasars from the Sloan Digital Sky Survey
• Moving mesh cosmology: tracing cosmological gas accretion
• The close environments of accreting massive black holes are shaped by radiative feedback
• The first ultraviolet quasar stacked spectrum at z=2.4 from WFC3
• Scaling Properties of a Complete X-ray Selected Galaxy Group Sample
• HeII Reionization and its Effect on the IGM
• Quasar Quartet Embedded in Giant Nebula Reveals Rare Massive Structure in Distant Universe
• A refined sub-grid model for black hole accretion and AGN feedback in large cosmological simulations
• The impact of mechanical AGN feedback on the formation of massive early-type galaxies
• The large and small scale properties of the intergalactic gas in the Slug Ly-alpha nebula revealed by MUSE HeII emission observations
• The Co-Formation of Spheroids and Quasars Traced in their Clustering
• The dependence of cosmic ray driven galactic winds on halo mass
• Mapping Neutral Hydrogen During Reionization with the Ly-alpha Emission from Quasar Ionization Fronts
• Stopping Cooling Flows with Jets
• Probing the Hot X-ray Corona around the Massive Spiral Galaxy, NGC 6753, Using Deep XMM-Newton observations
• Impact of Lyman alpha pressure on metal-poor dwarf galaxies
• The role of thermal evaporation in galaxy formation
• The angular momentum of cosmological coronae and the inside-out growth of spiral galaxies
• Time-Dependent Cooling in Photoionized Plasma
• Gas flows in the circumgalactic medium around simulated high-redshift galaxies
• Thermal instability and multi-phase interstellar medium in the first galaxies
• The Chandra COSMOS Legacy Survey: Clustering of X-ray selected AGN at 2.9<z<5.5 using photometric redshift Probability Distribution Functions
• Giant Ly-alpha nebulae in the high redshift (z>2) Universe

Cited by in corpus (8)

• Probing the AGN Unification Model at redshift z $\sim$ 3 with MUSE observations of giant Ly$\alpha$ nebulae
• Most of the cool CGM of star-forming galaxies is not produced by supernova feedback
• A Multiwavelength Study of ELAN Environments (AMUSE${}^2$). Mass budget, satellites spin alignment and gas infall in a massive $z\sim 3$ quasar host halo
• The galaxy-halo connection of disc galaxies over six orders of magnitude in stellar mass
• Characterizing the Circumgalactic Medium of Quasars at z $\sim$ 2.2 through H$\alpha$ and Ly$\alpha$ Emission
• A weak Ly$\alpha$ halo for an extremely bright Little Red Dot: Indications of enshrouded SMBH growth
• Quasar lifetime measurements from extended Ly$\alpha$ nebulae at $z\sim 6$
• Resolving circumgalactic gas flows around a z$\approx$3.6 quasar using MUSE and ALMA