摘要:We studied physical properties of matter in 24 544 filaments ranging from 30 to 100 Mpc in length, identified in the Sloan Digital Sky Survey. We stacked the Comptonizationymap produced by the Planck Collaboration around the filaments, excluding the resolved galaxy groups and clusters above a mass of ∼3 × 1013 M⊙. We detected the thermal Sunyaev-Zel’dovich signal for the first time at a significance of 4.4σin filamentary structures on such a large scale. We also stacked thePlanckcosmic microwave background lensing convergence map in the same manner and detected the lensing signal at a significance of 8.1σ. To estimate physical properties of the matter, we considered an isothermal cylindrical filament model with a density distribution following aβ-model (β= 2/3). Assuming that the gas distribution follows the dark matter distribution, we estimate that the central gas and matter overdensityδand gas temperatureTeareδ= 19.0−12.1+27.3andTe= 1.4−0.4+0.4× 106K, which results in a measured baryon fraction of 0.080−0.051+0.116× Ωb.
关键词:encosmology: observationslarge-scale structure of Universe