The Warm-Hot Intergalactic Medium: Emission Measures, Surface Brightness and Why the Missing Baryons Hide

This paper computes emission measures, surface brightness and why the missing baryons hide from stated published inputs, with every number produced by the deposited script. The headline results are: emission measure of the model filament = 4.61e+14 per cm^5, 0.5-2 keV surface brightness at 1e7 K = 5.80e-11 erg/cm^2/s/deg^2, 1e7 K surface brightness as a fraction of the soft background intensity = 0.00176, gas mass of the model filament segment = 2.73e+12 solar masses, cooling time of the filament gas at 1e7 K = 4.00e+12 years, hydrogen column through the filament = 7.68e+19 per cm^2. The calculation is a computation from standard plasma and gravitation physics applied to values reported by Chandra, XMM-Newton and eROSITA studies; it is simulated and computed, not measured. The inputs, the formulae and the sensitivity of each result to its assumptions are stated in full, so that the arithmetic can be checked, rerun with different inputs, and used as a reference for the systems concerned.