Radiative transfer through the intergalactic medium

Radiative Transfer Effects during Photoheating of the Intergalactic Medium

The thermal history of the intergalactic medium (IGM) after reionization is to a large extent determined by photoheating. Here we demonstrate that calculations of the photoheating rate which neglect radiative transfer effects substantially underestimate the energy input during and after reionization. The neglect of radiative transfer effects results in temperatures of the IGM which are too low ...

Heating the intergalactic medium by radiative decay of neutrinos

Assuming that there exists a species of heavy sterile neutrinos (mν > 1 keV) and their decays can serve as a heating source of the hot gas in galaxy clusters, we study how the observational constraints on cooling flow limit the mass of these sterile neutrinos. We predict a relation among the luminosity, total mass and the redshift of a cluster, and we compare this relation with data from 12 clu...

Intergalactic Medium

Simulations of the Intergalactic Medium

I present a review by epoch of baryons in the intergalac-tic medium (IGM), from the first star until today. Recent observations indicate a protracted period of reionization, suggesting multiple populations of reionizers; detection of these z ∼ > 6 sources is a key goal that is now coming within reach. The optical Lyman alpha forest (2 ∼ < z ∼ < 4) is well-described by the Fluctuating Gunn-Peter...

The thermal history of the intergalactic medium

At redshifts z2, most of the baryons reside in the smooth intergalactic medium which is responsible for the low column density Lyα forest. This photoheated gas follows a tight temperature-density relation which introduces a cut-off in the distribution of widths of the Lyα absorption lines (b-parameters) as a function of column density. We have measured this cut-off in a sample of nine high reso...