http://arxiv.org/abs/1504.04011
We estimate the amount of the missing baryons detected by the Planck measurements of the kinetic Sunyaev-Zeldovich effect (kSZ) around members of the Central Galaxy Catalogue (CGC) from the seventh release of the Sloan Survey. We use two statistics yielding evidence for kSZ signal, namely the pairwise peculiar momentum and the correlation function of the kSZ temperature estimates and predicted line-of-sight peculiar velocities. We find that both statistics yield consistent measurements of the Thomson optical depth $\tau_{\rm T}$ in the range of $0.5$-$1.4\times 10^{-4}$ for angular apertures that, on average, correspond to a range of distances of $>1$ to almost $3$ virial radii from the centres of the CG host halos. We find that, for the larger apertures for which we still have significant ($2$-$2.5\,\sigma$) kSZ detection, the regions probed around CGs contain roughly half the total amount of baryons present in the cosmological volume sampled by the Sloan footprint at $z\simeq 0.12$. Furthermore, under the assumption that baryons trace the dark matter distribution, our $\tau_{\rm T}$ measurements are compatible with having detected all the missing baryons around the CGs. Finally, our kSZ measurements yield no evidence for a kSZ dipole on the positions the CGs, providing the strongest constraints on the local bulk flow at a distance of $350$ $h^{-1}$ Mpc (below $290$ km s$^{-1}$ at 95% confidence level), and adding further evidence for the Copernican principle of homogeneity.
C. Hernandez-Monteagudo, Y. Ma, F. Kitaura, et. al.
Fri, 17 Apr 15
50/54
Comments: 5 pages, 3 plots, submitted