SIMBAD references

2020ApJ...896..136B - Astrophys. J., 896, 136-136 (2020/June-3)

Modeling photoionized turbulent material in the circumgalactic medium. II. Effect of turbulence within a stratified medium.

BUIE II E., GRAY W.J., SCANNAPIECO E. and SAFARZADEH M.

Abstract (from CDS):

The circumgalactic medium (CGM) of nearby star-forming galaxies shows clear indications of O VI absorption accompanied by little to no detectable N V absorption. This unusual spectral signature, accompanied by highly nonuniform absorption from lower-ionization-state species, indicates that the CGM must be viewed as a dynamic, multiphase medium, such as occurs in the presence of turbulence. Motivated by previous isotropic turbulent simulations, we carry out chemodynamical simulations of stratified media in a Navarro-Frenk-White (NFW) gravitational potential with a total mass of 1012 M and turbulence that decreases radially. The simulations assume a metallicity of 0.3 Z and a redshift-zero metagalatic UV background, and they track ionizations, recombinations, and species-by-species radiative cooling using the MAIHEM package. We compare a suite of ionic column densities with the COS-Halos sample of low-redshift star-forming galaxies. Turbulence with an average one-dimensional velocity dispersion of ≃40 km s–1, corresponding to an energy injection rate of ≃4 x 1049 erg yr–1, produces a CGM that matches many of the observed ionic column densities and ratios. In this simulation, the NNV/NOVI ratio is suppressed from its equilibrium value due to a combination of radiative cooling and cooling from turbulent mixing. This level of turbulence is consistent with expectations from observations of better constrained, higher-mass systems and could be sustained by energy input from supernovae, gas inflows, and dynamical friction from dark matter subhalos. We also conduct a higher resolution ≃40 km s–1 run, which yields smaller-scale structures but remains in agreement with observations.

Abstract Copyright: © 2020. The American Astronomical Society. All rights reserved.

Journal keyword(s): Circumgalactic medium - Astrochemistry

Simbad objects: 3

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2020ApJ...896..136B and select 'bookmark this link' or equivalent in the popup menu