Testing the effect of galactic feedback on the IGM at z∼ 6 with metal-line absorbers

Keating, Laura C.; Puchwein, Ewald; Haehnelt, Martin G.; Bird, Simeon; Bolton, James S.

Abstract

We present models of low- and high-ionization metal-line absorbers (O i, C ii, C iv and Mg ii) during the end of the reionization epoch, at z ∼ 6. Using four cosmological hydrodynamical simulations with different feedback schemes (including the Illustris and Sherwood simulations) and two different choices of hydro-solver, we investigate how the overall incidence rate and equivalent width distribution of metal-line absorbers varies with the galactic wind prescription. We find that the O i and C ii absorbers are reasonably insensitive to the feedback scheme. All models, however, struggle to reproduce the observations of C iv and Mg ii, which are probing down to lower overdensities than O i and C ii at z ∼ 6, suggesting that the metals in the simulations are not being transported out into the intergalactic medium efficiently enough. The situation is improved but not resolved if we choose a harder (but still reasonable) and/or (locally) increased UV background at z ∼ 6.

Citation

Keating, L. C., Puchwein, E., Haehnelt, M. G., Bird, S., & Bolton, J. S. (2016). Testing the effect of galactic feedback on the IGM at z∼ 6 with metal-line absorbers. Monthly Notices of the Royal Astronomical Society, 461(1), 606-626. https://doi.org/10.1093/mnras/stw1306

• Journal Article Type: Article
• Acceptance Date: May 27, 2016
• Online Publication Date: Jun 15, 2016
• Publication Date: Sep 1, 2016
• Deposit Date: Sep 22, 2016
• Publicly Available Date: Sep 22, 2016
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 461
• Issue: 1
• Pages: 606-626
• DOI: https://doi.org/10.1093/mnras/stw1306
• Keywords: Galaxies High-redshift, Intergalactic medium, Quasars, Absorption lines, Reionization, First stars
• Public URL: https://nottingham-repository.worktribe.com/output/795018
• Publisher URL: http://mnras.oxfordjournals.org/content/461/1/606
• Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2016 the Royal Astronomical Society Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
• Contract Date: Sep 22, 2016