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The properties of Ly-alpha emitting galaxies in hierarchical galaxy formation models

M. Le Delliou·C. G. Lacey·C. M. Baugh·S. L. Morris
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Abstract

We present detailed predictions for the properties of Ly-alpha-emitting galaxies in the framework of the Lambda-CDM cosmology, calculated using the semi-analytical galaxy formation model GALFORM. We explore a model which assumes a top-heavy IMF in starbursts, and which has previously been shown to explain the sub-mm number counts and the luminosity function of Lyman-break galaxies at high redshift. We show that this model, with the simple assumption that a fixed fraction of Ly-alpha photons escape from each galaxy, is remarkably successful at explaining the observed luminosity function of Ly-alpha emitters over the redshift range 3 7, a redshift range which is starting to be be probed by near-IR surveys and using new instruments such as DAzLE.

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M. Le Delliou, C. G. Lacey, C. M. Baugh, S. L. Morris. 2005-10-25. The properties of Ly-alpha emitting galaxies in hierarchical galaxy formation models. https://doi.org/10.1111/j.1365-2966.2005.09797.x

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