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The abundance of Lyman-(α) emitters in hierarchical models

Morgan Le Delliou·Cedric Lacey·Carlton M. Baugh·Bruno Guiderdoni·Roland Bacon·Helene Courtois·Thierry Sousbie·Simon L. Morris
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Abstract

We present predictions for the abundance of Ly-$α$ emitters in hierarchical structure formation models. We use the {\tt GALFORM} semi-analytical model to explore the impact on the predicted counts of varying assumptions about the escape fraction of Ly-$α$ photons, the redshift at which the universe reionised and the cosmological density parameter. A model with a fixed escape fraction gives a remarkably good match to the observed counts over a wide redshift interval. We present predictions for the expected counts in a typical observation with the Multi Unit Spectroscopic Explorer instrument proposed for the Very Large Telescope.

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Morgan Le Delliou, Cedric Lacey, Carlton M. Baugh, Bruno Guiderdoni, Roland Bacon, Helene Courtois, Thierry Sousbie, Simon L. Morris. 2004-11-08. The abundance of Lyman-(α) emitters in hierarchical models. https://doi.org/10.1111/j.1745-3933.2005.00007.x

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