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arXiv · 1704.03473

Theoretical study of an LAE-CIV absorption pair at z = 5.7

L. A. García·E. Tescari·E. V. Ryan-Weber·J. S. B. Wyithe
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Abstract

We present a theoretical model to predict the properties of an observed $z =$ 5.72 Lyman $\alpha$ emitter galaxy - CIV absorption pair separated by 1384 comoving kpc/h. 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 CIV absorber. We find a plausible explanation for the metal enrichment in the context of our simulations: a dwarf galaxy with $M_{\star} =$ 1.87 $\times$ 10$^{9} M_{\odot}$ located 119 comoving kpc/h away with a wind velocity of $\sim$ 100 km/s launched at $z \sim$ 7. Such a dwarf ($M_{\text{UV}} =$ - 20.5) is fainter than the detection limit of the observed example. In a general analysis of galaxy - CIV absorbers, we find galaxies with -20.5 $< M_{\text{UV}} <$ - 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.

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L. A. García, E. Tescari, E. V. Ryan-Weber, J. S. B. Wyithe. 2017-04-11. Theoretical study of an LAE-CIV absorption pair at z = 5.7. https://doi.org/10.1093/mnrasl/slx053

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