Constraining reionization using the thermal history of the baryons

摘要: The thermal evolution of the intergalactic medium (IGM) depends on reionization history universe. Numerical simulations indicate that low density IGM, which is responsible for column Ly-alpha forest, follows a well defined temperature-density relation. This results in cut-off distribution line widths as function density. We use hydrodynamic to calibrate relation between and apply this Keck spectra spanning redshift range z=2-4.5. find temperature peaks at z~3 interpret evidence reheating due helium.