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The Sloan Digital Sky Survey has validated and made publicly available its First Data Release. This consists of 2099 square degrees of five-band (u g r i z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 1360 square degrees of this area, and tables of measured parameters from these data. The imaging(More)
We present results from a large volume simulation of Hydrogen reionization. We combine 3d radiative transfer calculations and an N-body simulation, describing structure formation in the intergalactic medium (IGM), to detail the growth of HII regions around high redshift galaxies. Our N-body simulation tracks 1024 dark matter particles, in a cubical box of(More)
We investigate the luminosity dependence of quasar clustering, inspired by numerical simulations of galaxy mergers that incorporate black hole growth. These simulations have motivated a new interpretation of the quasar luminosity function. In this picture, the bright end of the quasar luminosity function consists of quasars radiating nearly at their peak(More)
The ionizing background determines the ionization balance and the thermodynamics of the cosmic gas. It is therefore a fundamental ingredient to theoretical and empirical studies of both the IGM and galaxy formation. We present here a new calculation of its spectrum that satisfies the empirical constraints we recently obtained by combining state-of-the-art(More)
We calculate the impact of the intergalactic medium (IGM) on the observed Lyα lines emitted by galaxies in an ionised IGM at z > 4. Our model accounts for gas clumping in the IGM and for the fact that high-redshift galaxies reside in overdense regions, which causes the velocity field of the IGM to depart from the Hubble flow. The observed shape of the Lyα(More)
We show that near-infrared observations of the red side of the Lyα line from a single gamma ray burst (GRB) afterglow cannot be used to constrain the global neutral fraction of the intergalactic medium (IGM), x̄H , at the GRB’s redshift to better than δx̄H ∼ 0.3, because some GRB sight-lines will encounter more neutral hydrogen than others owing to the(More)
We forecast the sensitivity with which the MurchisonWidefield Array (MWA) can measure the 21 cm power spectrum of cosmic hydrogen, using radiative transfer simulations to model reionization and the 21 cm signal. The MWA is sensitive to roughly a decade in scale (wavenumbers of k ∼ 0.1−1hMpc−1), with foreground contamination precluding measurements on larger(More)
Steven R. Furlanetto, Adam Lidz, Abraham Loeb, Matthew McQuinn, Jonathan R. Pritchard, Paul R. Shapiro, Marcelo A. Alvarez, Donald C. Backer, Judd D. Bowman, Jack O. Burns, Chris L. Carilli, Renyue Cen, Asantha Cooray, Nickolay Y. Gnedin, Lincoln J. Greenhill, Zoltan Haiman, Jacqueline N. Hewitt, Christopher M. Hirata, Joseph Lazio, Andrei Mesinger, Piero(More)
The universe is permeated by a network of filaments, sheets, and knots collectively forming a "cosmic web." The discovery of the cosmic web, especially through its signature of absorption of light from distant sources by neutral hydrogen in the intervening intergalactic medium, exemplifies the interplay between theory and experiment that drives science and(More)