Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and P l a n c k . II. Crosscorrelation measurements and cosmological constraints
Abstract
Crosscorrelations of galaxy positions and galaxy shears with maps of gravitational lensing of the cosmic microwave background (CMB) are sensitive to the distribution of largescale structure in the Universe. Such crosscorrelations are also expected to be immune to some of the systematic effects that complicate correlation measurements internal to galaxy surveys. We present measurements and modeling of the crosscorrelations between galaxy positions and galaxy lensing measured in the first three years of data from the Dark Energy Survey with CMB lensing maps derived from a combination of data from the 2500 deg^{2} SPTSZ survey conducted with the South Pole Telescope and fullsky data from the Planck satellite. The CMB lensing maps used in this analysis have been constructed in a way that minimizes biases from the thermal Sunyaev Zel'dovich effect, making them well suited for crosscorrelation studies. The total signaltonoise of the crosscorrelation measurements is 23.9 (25.7) when using a choice of angular scales optimized for a linear (nonlinear) galaxy bias model. We use the crosscorrelation measurements to obtain constraints on cosmological parameters. For our fiducial galaxy sample, which consist of four bins of magnitudeselected galaxies, we find constraints of Ω_{m}=0.272_{0.052}^{+0.032} and S_{8}≡σ_{8}√{Ω_{m}/0.3 }=0.736_{0.028}^{+0.032} (Ω_{m}=0.245_{0.044}^{+0.026} and S_{8}=0.734_{0.028}^{+0.035} ) when assuming linear (nonlinear) galaxy bias in our modeling. Considering only the crosscorrelation of galaxy shear with CMB lensing, we find Ω_{m}=0.270_{0.061}^{+0.043} and S_{8}=0.740_{0.029}^{+0.034} . Our constraints on S_{8} are consistent with recent cosmic shear measurements, but lower than the values preferred by primary CMB measurements from Planck.
 Publication:

Physical Review D
 Pub Date:
 January 2023
 DOI:
 10.1103/PhysRevD.107.023530
 arXiv:
 arXiv:2203.12440
 Bibcode:
 2023PhRvD.107b3530C
 Keywords:

 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 25 pages, 19 figures, submitted to PRD