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Title: CMB lensing power spectrum biases from galaxies and clusters using high-angular resolution temperature maps

The lensing power spectrum from cosmic microwave background (CMB) temperature maps will be measured with unprecedented precision with upcoming experiments, including upgrades to the Atacama Cosmology Telescope and the South Pole Telescope. Achieving significant improvements in cosmological parameter constraints, such as percent level errors on σ{sub 8} and an uncertainty on the total neutrino mass of ∼50 meV, requires percent level measurements of the CMB lensing power. This necessitates tight control of systematic biases. We study several types of biases to the temperature-based lensing reconstruction signal from foreground sources such as radio and infrared galaxies and the thermal Sunyaev-Zel'dovich effect from galaxy clusters. These foregrounds bias the CMB lensing signal due to their non-Gaussian nature. Using simulations as well as some analytical models we find that these sources can substantially impact the measured signal if left untreated. However, these biases can be brought to the percent level if one masks galaxies with fluxes at 150 GHz above 1 mJy and galaxy clusters with masses above M {sub vir} = 10{sup 14} M {sub ☉}. To achieve such percent level bias, we find that only modes up to a maximum multipole of l {sub max} ∼ 2500 should be included inmore » the lensing reconstruction. We also discuss ways to minimize additional bias induced by such aggressive foreground masking by, for example, exploring a two-step masking and in-painting algorithm.« less
Authors:
;  [1] ;  [2] ;  [3] ;  [4] ;  [5]
  1. Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States)
  2. Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)
  3. Department of Physics, McGill University, 3600 Rue University, Montreal, Quebec H3A 2T8 (Canada)
  4. Berkeley Center for Cosmological Physics, Department of Physics, University of California, and Lawrence Berkeley National Labs, Berkeley, CA 94720 (United States)
  5. Department of Physics, Department of Astronomy and Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520 (United States)
Publication Date:
OSTI Identifier:
22357032
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 786; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; ALGORITHMS; BACKGROUND RADIATION; COSMOLOGY; GALAXIES; GALAXY CLUSTERS; GHZ RANGE; GRAVITATIONAL LENSES; LIMITING VALUES; MASS; NEUTRINOS; RELICT RADIATION; RESOLUTION; RESPIRATORS; SIMULATION; SPECTRA; TELESCOPES; UNIVERSE