Zoltán Haiman

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We compute the expected angular power spectrum of the cosmic Far Infrared Background (FIRB). We find that the signal due to source correlations dominates the shot–noise for l <∼ 1000 and results in anisotropies with rms amplitudes ( √ l(l+ 1)Cl/2π) between 5% and 10% of the mean for l >∼ 150. The angular power spectrum depends on several unknown quantities,(More)
Primordial gas in protogalactic dark matter (DM) halos with virial temperatures Tvir ∼ > 10K begins to cool and condense via atomic hydrogen. Provided this gas is irradiated by a strong ultraviolet (UV) flux and remains free of H2 and other molecules, it has been proposed that it may avoid fragmentation, and lead to the rapid formation of a supermassive(More)
The first massive astrophysical black holes likely formed at high redshifts (z ∼ > 10) at the centers of low mass (∼ 10 M⊙) dark matter concentrations. These black holes grow by mergers and gas accretion, evolve into the population of bright quasars observed at lower redshifts, and eventually leave the supermassive black hole remnants that are ubiquitous at(More)
The ubiquity of supermassive black holes (SMBHs) at the centers of nearby luminous galaxies can arise from the multiple mergers experienced by dark matter halos in hierarchical structure formation models, even if only a small fraction of these galaxies harbor SMBHs at high redshifts. We illustrate this possibility using cosmological Monte Carlo simulations(More)
The recent discovery of a high optical depth τ to Thomson scattering from the Wilkinson Microwave Anisotropy Probe (WMAP) data implies that significant reionization took place at redshifts z> 6. This discovery has important implications for the sources of reionization, and allows, for the first time, constraints to be placed on physical reionization(More)
We use a physically motivated semi–analytic model, based on the mass function of dark matter halos, to predict the number of radio–loud quasars as a function of redshift and luminosity. Simple models in which the central BH mass scales with the velocity dispersion of its host halo as Mbh ∝ σ5 halo have been previously found to be consistent with a number of(More)
The recent discovery of a Gunn–Peterson (GP) trough in the spectrum of the redshift 6.28 SDSS quasar has raised the tantalizing possibility that we have detected the reionization of the universe. However, a neutral fraction (of hydrogen) as small as 0.1% is sufficient to cause the GP trough, hence its detection alone cannot rule out reionization at a much(More)
The early stage in the formation of a galaxy inevitably involves a spatially extended distribution of infalling, cold gas. If a central luminous quasar turned on during this phase, it would result in significant extended Lyα emission (possibly accompanied by other lines), detectable as a “fuzz” of characteristic angular diameter of a few arcseconds, and(More)
Supermassive black hole binaries (SMBHBs) in galactic nuclei are thought to be a common by–product of major galaxy mergers. We use simple disk models for the circumbinary gas and for the binary-disk interaction to follow the orbital decay of SMBHBs with a range of total masses (M) and mass ratios (q), through physically distinct regions of the disk, until(More)
For a source of Lyα radiation embedded in a neutral intergalactic medium (IGM) prior to the reionization epoch, the emission line is strongly suppressed by the intervening IGM. The damping wing of the so–called “Gunn-Peterson trough” can extend to the red side of the emission line, and erase a significant fraction of the total line flux. However, the(More)