Published in "Gas Accretion onto Galaxies", Astrophysics and Space Science Library, Volume 430. ISBN 978-3-319-52511-2. Springer International Publishing AG, 2017, p. 145.
https://arxiv.org/abs/1612.00451

For a PDF version of the article, click here.

Abstract: Cold-mode gas accretion onto galaxies is a direct prediction of ΛCDM simulations and provides galaxies with fuel that allows them to continue to form stars over the lifetime of the Universe. Given its dramatic influence on a galaxy's gas reservoir, gas accretion has to be largely responsible for how galaxies form and evolve. Therefore, given the importance of gas accretion, it is necessary to observe and quantify how these gas flows affect galaxy evolution. However, observational data have yet to conclusively show that gas accretion ubiquitously occurs at any epoch. Directly detecting gas accretion is a challenging endeavor and we now have obtained a significant amount of observational evidence to support it. This chapter reviews the current observational evidence of gas accretion onto star-forming galaxies.

Table of Contents

• INTRODUCTION
• THE SPATIAL DISTRIBUTION OF THE CIRCUMGALACTIC MEDIUM
• Circumgalactic Gas Radial Distribution
• Circumgalactic Gas Spatial Distribution
• CIRCUMGALACTIC GAS KINEMATICS
• Internal or Intrinsic Gas Kinematics
• Relative Gas-Galaxy Kinematics
• CIRCUMGALACTIC AND GALAXY GAS-PHASE METALLICITIES
• PUTTING IT ALL TOGETHER
• DIRECT IMAGING OF GAS ACCRETION
• SUMMARY
• REFERENCES