Ravi K. Sheth

TL;DR: In this article, the Sloan Digital Sky Survey (SDSS) is used to measure the statistical properties of galaxies within the local Universe. But the results of the SDSS data are limited to a very small area and the highly correlated nature of the error covariance matrix does not yet provide a definitive characterization of departures from the power-law form.

TL;DR: In this article, the authors describe a model of dark matter halo abundances and clustering which combines the two most widely used approaches to this problem: that based on peaks and the other based on excursion sets.

TL;DR: In this paper, the authors use hydrodynamical simulations to show that the observed temperature increase associated with He II reionization leads to a relatively sudden decrease in eff around the reionisation epoch of ≈10%.

TL;DR: In this article, the authors use hydrodynamical simulations to show that the temperature increase associated with He II reionization leads to a relatively sudden decrease in tau around the reionisation epoch of ~ 10 per cent.

TL;DR: In this article, a simple model for estimating the mass growth histories of dark matter halos was developed, which is based on a t to the formation time distribution, where formation is dened as the earliest time that the main branch of the merger tree contains a fraction f of the nal mass M. The model is used to estimate how the distribution of halo concentrations may be expected to depend on mass, redshift and the expansion history of the background cosmology.