Theoretical study of an LAE–C iv absorption pair at z = 5.7

• Published in: Monthly notices of the Royal Astronomical Society. Letters Vol. 469; no. 1; pp. L53 - L57
• Main Authors: García, L. A., Tescari, E., Ryan-Weber, E. V., Wyithe, J. S. B.
• Format: Journal Article
• Language: English
• Published: Oxford University Press 21-07-2017
• Subjects: methods: numerical; intergalactic medium; cosmology: theory
• ISSN: 1745-3925; 1745-3933
• DOI: 10.1093/mnrasl/slx053

Abstract
We present a theoretical model to predict the properties of an observed z = 5.72 Lyman α emitter galaxy–C iv absorption pair separated by 1384 comoving kpc h
−1. We use the separation of the pair and an outflow velocity/time travelling argument to demonstrate that the observed galaxy cannot be the source of metals for the C iv absorber. We find a plausible explanation for the metal enrichment in the context of our simulations: a dwarf galaxy with M
⋆ = 1.87 × 109 M⊙ located 119 comoving kpc h
−1 away with a wind velocity of ∼100 km s−1 launched at z ∼ 7. Such a dwarf (M
UV = −20.5) is fainter than the detection limit of the observed example. In a general analysis of galaxy–C iv absorbers, we find galaxies with − 20.5 <M
UV < −18.8 are responsible for the observed metal signatures. In addition, we find no correlation between the mass of the closest galaxy to the absorber and the distance between them, but a weak anti-correlation between the strength of the absorption and the separation of galaxy–absorber pairs.