Journal article

Suppressing the Thermal SZ-induced Variance in CMB-cluster Lensing Estimators

Sanjaykumar Patil, Srinivasan Raghunathan, Christian L Reichardt

Astrophysical Journal | American Astronomical Society | Published : 2020


Accurate galaxy cluster mass measurements from the gravitational lensing of the cosmic microwave background temperature maps depend on mitigating potential biases from the cluster's own thermal Sunyaev–Zel'dovich (SZ) effect signal. Quadratic lensing estimators use a pair of maps to extract the lensing signal: a large-scale gradient map and a small-scale lensing map. The SZ bias can be eliminated by using an SZ-free map in the pair, with the gradient map being favored for signal-to-noise reasons. However, while this approach eliminates the bias, the SZ power in small-scale lensing map adds extra variance that can become significant for high-mass clusters and low-noise surveys. In this work, ..

View full abstract

University of Melbourne Researchers


Awarded by NSF

Awarded by Australian Research Council

Awarded by Office of Science of the U.S. Department of Energy

Funding Acknowledgements

We thank Eric Baxter, Federico Bianchini, Thomas Crawford, Nikhel Gupta, Daisuke Nagai, and W. L. Kimmy Wu for useful discussions regarding this project.S.P. acknowledges support from MIPP, Laby Travel Bursary, and Melbourne International Engagement Award. S.R. acknowledges the support from NSF grants AST-1716965 and CSSI-1835865. The work at Melbourne is supported by the Australian Research Council's Discovery Projects scheme (DP150103208). We thank the high performance computation center at the University of Melbourne for providing access to the cluster We acknowledge the use of CAMB (Lewis et al. 2000) and HEALPIX (Gorski et al. 2005) routines. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.