2020A&A...637A..41T

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 Comptonization y map produced by the Planck Collaboration around the filaments, excluding the resolved galaxy groups and clusters above a mass of ∼3x10¹³M_☉. We detected the thermal Sunyaev-Zel'dovich signal for the first time at a significance of 4.4σ in filamentary structures on such a large scale. We also stacked the Planck cosmic 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 a β-model (β = 2/3). Assuming that the gas distribution follows the dark matter distribution, we estimate that the central gas and matter overdensity δ and gas temperature T_e are δ=19.0_–12.1^+27.3 and T_e=1.4_–0.4^+0.4x10⁶K, which results in a measured baryon fraction of 0.080_–0.051^+0.116xΩ_b.