Missing baryon problem

in the light of distant quasars reveal this gas lurking between clusters of galaxies.

However, by looking only at the hottest or the coolest material, we don't find nearly enough of it to account for the missing baryons.

It seems that the missing material must be in the intermediate temperature range.

It must be hot enough to still be a plasma, otherwise it'd produce absorption features, but it can't be so hot or dense as to emit detectable X-rays.

This tells us that the best hiding place for the missing baryons is the giant filaments that form the cosmic web stretching in between galaxy clusters.

That material would be cooler than the clusters themselves, but should at least be hot enough to form a plasma.

See, the vast tidal effects of nearby galaxies create shocks that can heat those baryons to hundreds of thousands or even millions of Kelvin.

Both teams report detection of the thermal Sunyaev-Zel'dovich effect with around five sigma significance, or to translate, they found the baryons.