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Title: A measurement of the cosmic microwave background B-mode polarization power spectrum at sub-degree scales with POLARBEAR

We report a measurement of the B-mode polarization power spectrum in the cosmic microwave background (CMB) using the POLARBEAR experiment in Chile. The faint B-mode polarization signature carries information about the universe's entire history of gravitational structure formation, and the cosmic inflation that may have occurred in the very early universe. Our measurement covers the angular multipole range 500 < ℓ < 2100 and is based on observations of an effective sky area of 25 deg{sup 2} with 3.'5 resolution at 150 GHz. On these angular scales, gravitational lensing of the CMB by intervening structure in the universe is expected to be the dominant source of B-mode polarization. Including both systematic and statistical uncertainties, the hypothesis of no B-mode polarization power from gravitational lensing is rejected at 97.2% confidence. The band powers are consistent with the standard cosmological model. Fitting a single lensing amplitude parameter A{sub BB} to the measured band powers, A{sub BB}=1.12±0.61(stat){sub −0.12}{sup +0.04}(sys)±0.07(multi), where A{sub BB} = 1 is the fiducial WMAP-9 ΛCDM value. In this expression, 'stat' refers to the statistical uncertainty, 'sys' to the systematic uncertainty associated with possible biases from the instrument and astrophysical foregrounds, and 'multi' to the calibration uncertainties that have amore » multiplicative effect on the measured amplitude A{sub BB}.« less
Authors:
 [1] ; ;  [2] ; ;  [3] ; ; ; ; ; ;  [4] ; ;  [5] ;  [6] ; ;  [7] ; ;  [8] ;  [9] ;  [10] more »; ; « less
  1. School of Physics and Astronomy, Cardiff University, Cardiff CF10 3XQ (United Kingdom)
  2. The Graduate University for Advanced Studies, Hayama, Miura District, Kanagawa 240-0115 (Japan)
  3. Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO 80309 (United States)
  4. Department of Physics, University of California, San Diego, CA 92093-0424 (United States)
  5. Computational Cosmology Center, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)
  6. Department of Physics and Atmospheric Science, Dalhousie University, Halifax, NS, B3H 4R2 (Canada)
  7. Department of Physics, University of California, Berkeley, CA 94720 (United States)
  8. Physics Department, McGill University, Montreal, QC H3A 0G4 (Canada)
  9. AstroParticule et Cosmologie, Univ Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs de Paris, Sorbonne Paris Cité (France)
  10. Rutherford Appleton Laboratory, STFC, Swindon, SN2 1SZ (United Kingdom)
Publication Date:
OSTI Identifier:
22370373
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 794; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; ASTROPHYSICS; BACKGROUND RADIATION; CALIBRATION; COSMOLOGY; GRAVITATIONAL LENSES; HYPOTHESIS; INFLATIONARY UNIVERSE; POLARIZATION; RELICT RADIATION; RESOLUTION; SPECTRA; UNIVERSE