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Title: Measuring galaxy cluster masses with CMB lensing using a Maximum Likelihood estimator: statistical and systematic error budgets for future experiments

We develop a Maximum Likelihood estimator (MLE) to measure the masses of galaxy clusters through the impact of gravitational lensing on the temperature and polarization anisotropies of the cosmic microwave background (CMB). We show that, at low noise levels in temperature, this optimal estimator outperforms the standard quadratic estimator by a factor of two. For polarization, we show that the Stokes Q/U maps can be used instead of the traditional E- and B-mode maps without losing information. We test and quantify the bias in the recovered lensing mass for a comprehensive list of potential systematic errors. Using realistic simulations, we examine the cluster mass uncertainties from CMB-cluster lensing as a function of an experiment’s beam size and noise level. We predict the cluster mass uncertainties will be 3 - 6% for SPT-3G, AdvACT, and Simons Array experiments with 10,000 clusters and less than 1% for the CMB-S4 experiment with a sample containing 100,000 clusters. The mass constraints from CMB polarization are very sensitive to the experimental beam size and map noise level: for a factor of three reduction in either the beam size or noise level, the lensing signal-to-noise improves by roughly a factor of two.
 [1] ;  [1] ;  [2] ;  [1] ;  [3] ;  [4] ;  [5] ;  [6] ;  [1]
  1. Univ. of Melbourne, Parkville VIC (Australia). School of Physics
  2. Univ. of Pennsylvania, Philadelphia, PA (United States). Dept. of Physics and Astronomy
  3. Argonne National Lab. (ANL), Argonne, IL (United States). High Energy Physics Div.; Univ. of Chicago, IL (United States). Kavli Inst. for Cosmological Physics (KICP)
  4. Univ. of Chicago, IL (United States). Kavli Inst. for Cosmological Physics (KICP); Univ. of Chicago, IL (United States). Dept. of Astronomy and Astrophysics
  5. Univ. of Illinois, Urbana, IL (United States). Dept. of Astronomy, Dept. of Physics
  6. Univ. of Chicago, IL (United States). Dept. of Astronomy and Astrophysics
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2017; Journal Issue: 08; Journal ID: ISSN 1475-7516
Institute of Physics (IOP)
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF); Australian Research Council
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; CMBR polarization; Galaxy clusters; Weak gravitational lensing
OSTI Identifier: