Unveiling the baryons in large-scale structures

Simulations and observations indicate that galaxy overdensities are good tracersof the dark matter largescale structures (LSS) and therefore of the diffusewarmhot phase (WHIM) that should be associated with them. The WHIM in LSSshould have large column densities, and therefore should be much easier todetect than the low density WHIM targeted so far through absorption line studieson random lines of sight (with controversial results). The strategy of searchingfor WHIM signatures in known LSS is safer and more robust, since the redshift ofthe absorber is known a priori. We have selected 13 bright blazars just in thebackground of 6 known LSS. We propose to observe these blazars (in outburstphase) with 2 TOO observations of 100ks each to probe the WHIM in the foreground LSS. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]