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تسجيل مستخدم جديدMeasurement of the pairwise kinematic Sunyaev-Zeldovich effect with Planck and BOSS data
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We present a new measurement of the kinetic Sunyaev-Zeldovich effect (kSZ) using Planck cosmic microwave background (CMB) and Baryon Oscillation Spectroscopic Survey (BOSS) data. Using the `LowZ North/South galaxy catalogue from BOSS DR12, and the group catalogue from BOSS DR13, we evaluate the mean pairwise kSZ temperature associated with BOSS galaxies. We construct a `Central Galaxies Catalogue (CGC) which consists of isolated galaxies from the original BOSS data set, and apply the aperture photometry (AP) filter to suppress the primary CMB contribution. By constructing a halo model to fit the pairwise kSZ function, we constrain the mean optical depth to be $bar{tau}=(0.53pm0.32)times10^{-4}(1.65,sigma)$ for `LowZ North CGC, $bar{tau}=(0.30pm0.57)times10^{-4}(0.53,sigma)$ for `LowZ South CGC, and $bar{tau}=(0.43pm0.28)times10^{-4}(1.53,sigma)$ for `DR13 Group. In addition, we vary the radius of the AP filter and find that the AP size of $7,{rm arcmin}$ gives the maximum detection for $bar{tau}$. We also investigate the dependence of the signal with halo mass and find $bar{tau}=(0.32pm0.36)times10^{-4}(0.8,sigma)$ and $bar{tau}=(0.67pm0.46)times10^{-4}(1.4,sigma)$ for `DR13 Group with halo mass restricted to, respectively, less and greater than its median halo mass, $10^{12}, h^{-1}{rm M}_{odot}$. For the `LowZ North CGC sample restricted to $M_{rm h} gtrsim 10^{14}, h^{-1}{rm M}_odot$ there is no detection of the kSZ signal because these high mass halos are associated with the high-redshift galaxies of the LowZ North catalogue, which have limited contribution to the pairwise kSZ signals.
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