Measuring the temperature of the intergalactic medium

摘要: Numerical simulations indicate that the smooth, photoionized intergalactic medium (IGM) responsible for low column density Lyman-alpha forest follows a well defined temperature-density relation. We show such an equation of state results in cutoff distribution line widths (b-parameters) as function (N) absorption lines. This explains existence lower envelope which is clearly seen scatter plots b(N)-distribution observed QSO spectra. The intercept and slope this can be used to measure IGM. Measuring evolution with redshift will allow us put tight constraints on reionization history universe.