Mass Calibration of Optically Selected DES Clusters Using a Measurement of CMB-cluster Lensing with SPTpol Data

• Published in: The Astrophysical Journal
• Main Authors: Raghunathan, S., Crites, A. T., Padin, S.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Astronomical Society 2019
• Subjects: cosmic background radiation – galaxies: clusters: general – gravitational lensing: weak; Kavli; South Pole; South pole
• Online Access: https://doi.org/10.3847/1538-4357/ab01ca

We use cosmic microwave background (CMB) temperature maps from the 500 deg2 SPTpol survey to measure the stacked lensing convergence of galaxy clusters from the Dark Energy Survey (DES) Year-3 redMaPPer (RM) cluster catalog. The lensing signal is extracted through a modified quadratic estimator designed to be unbiased by the thermal Sunyaev–Zel'dovich (tSZ) effect. The modified estimator uses a tSZ-free map, constructed from the SPTpol 95 and 150 GHz data sets, to estimate the background CMB gradient. For lensing reconstruction, we employ two versions of the RM catalog: a flux-limited sample containing 4003 clusters and a volume-limited sample with 1741 clusters. We detect lensing at a significance of 8.7σ(6.7σ) with the flux (volume)–limited sample. By modeling the reconstructed convergence using the Navarro–Frenk–White profile, we find the average lensing masses to be M_(200 m) = (1.62^(+0.32)_(-0.25) [stat.] ± 0.04 [sys.]) and (1.28^(+0.14)_(-0.18) [stat.] ± 0.03 [sys.] x 10^(14) M⊙ for the volume- and flux-limited samples, respectively. The systematic error budget is much smaller than the statistical uncertainty and is dominated by the uncertainties in the RM cluster centroids. We use the volume-limited sample to calibrate the normalization of the mass-richness scaling relation, and find a result consistent with the galaxy weak-lensing measurements from DES. © 2019 The American Astronomical Society. Received 2018 October 26; revised 2019 January 2; accepted 2019 January 22; published 2019 February 20. This work was performed in the context of the South Pole Telescope scientific program. SPT is supported by the National Science Foundation through grant PLR-1248097. Partial support is also provided by the NSF Physics Frontier Center grant PHY-1125897 to the Kavli Institute of Cosmological Physics at the University of Chicago, the Kavli Foundation, and the Gordon and Betty Moore Foundation grant GBMF 947. This research used resources of the National Energy Research Scientific Computing Center ...