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تسجيل مستخدم جديدTheoretical study of an LAE-CIV absorption pair at z = 5.7
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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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Metal absorption systems are products of star formation. They are believed to be associated with massive star forming galaxies, which have significantly enriched their surroundings. To test this idea with high column density CIV absorption systems at
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