A direct measure of free electron gas via the Kinematic Sunyaev-Zel'dovich effect in Fourier-space analysis

Understand

We present the measurement of the kinematic Sunyaev-Zel'dovich (kSZ) effect in Fourier space, rather than in real space.

• We measure the density-weighted pairwise kSZ power spectrum, the first use of this promising approach, by cross-correlating a cleaned Cosmic Microwave Background (CMB) temperature map, which jointly uses both Planck Release 2 and Wilkinson Microwave Anisotropy Probe nine-year data, with the two galaxy samples, CMASS and LOWZ, derived fr om the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12.
• With the current data, we constrain the average optical depth $\tau$ multiplied by the ratio of the Hubble parameter at redshift $z$ and the present day, $E=H/H_0$; we find $\tau E = (3.95\pm1.62)\times10^{-5}$ for LOWZ and $\tau E = ( 1.25\pm 1.06)\times10^{-5}$ for CMASS, with the optimal angular radius of an aperture photometry filter to estimate the CMB temperature distortion associ ated with each galaxy.
• By repeating the pairwise kSZ power analysis for various aperture radii, we measure the optical depth as a function of aperture ra dii.