Testing the effect of galactic feedback on the IGM at z ∼ 6 with metal-line absorbers. Issue 1 (15th June 2016)

• Record Type: Journal Article
• Authors: Keating, Laura C.; Puchwein, Ewald; Haehnelt, Martin G.; Bird, Simeon; Bolton, James S.
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 461:Issue 1(2016)
• Page Start: 606
• Page End: 626
• Publication Date: 2016-06-15
• Subjects: methods: numerical -- galaxies: high-redshift -- intergalactic medium -- quasars: absorption lines -- dark ages, reionization, first stars; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stw1306
• Languages: English
• ISSNs: 0035-8711

Abstract

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.