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A simple analytical model for the abundance of damped Ly-αabsorbers

T. Roy Choudhury·T. Padmanabhan
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Abstract

A simple analytical model for estimating the fraction (Ω_{gas}) of matter in gaseous form within the collapsed dark matter (DM) haloes is presented. The model is developed using (i) the Press-Schechter formalism to estimate the fraction of baryons in DM haloes, and (ii) the observational estimates of the star formation rate at different redshifts. The prediction for Ω_{gas} from the model is in broad agreement with the observed abundance of the damped Ly-αsystems. Furthermore, it can be used for estimating the circular velocities of the collapsed haloes at different redshifts, which could be compared with future observations.

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T. Roy Choudhury, T. Padmanabhan. 2002-04-01. A simple analytical model for the abundance of damped Ly-αabsorbers. https://doi.org/10.1086/340927

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