出版社:SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要:A significant fraction of the baryons in the low redshift Universe is expected to be in a warm-hot
phase (WHIM) with temperatures of the order of 105-107 K, and with moderate overdensities
d 10-100 (Cen & Ostriker 1999). This WHIM would be associated to a network of filaments
connecting the regions where clusters of galaxies are located. In this work, we have explored the
possibility of detecting this WHIM phase with PLANCK, by means of the Sunyaev-Zel’dovich
effect (SZE) associated to regions containing superclusters. We have used hydrodynamic simulations
including the gas physics, to identify those regions which are similar to present-day
superclusters. Six maps of the Comptonization parameter (y) at PLANCK resolution have been
prepared from these regions centered in a supercluster. For their analysis, we have excluded those
regions in the maps which are associated to identified clusters in the simulation, studying only
the SZ signal produced by the remaining gas in the supercluster. We find that the most intense
features in these proccesed maps are produced by small haloes (clumps in the simulations which
are not identified as clusters), although these clumps are part of filaments. PLANCK should be
able to detect at least one intense feature (y > 8106) not associated to a cluster for every 8
superclusters. The probability of observing those features is a strong function of the elongation
of the supercluster along the line of sight, so detections are most probable in highly elongated
superclusters.