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Title: A MEASUREMENT OF GRAVITATIONAL LENSING OF THE MICROWAVE BACKGROUND USING SOUTH POLE TELESCOPE DATA

Abstract

We use South Pole Telescope data from 2008 and 2009 to detect the non-Gaussian signature in the cosmic microwave background (CMB) produced by gravitational lensing and to measure the power spectrum of the projected gravitational potential. We constrain the ratio of the measured amplitude of the lensing signal to that expected in a fiducial {Lambda}CDM cosmological model to be 0.86 {+-} 0.16, with no lensing disfavored at 6.3{sigma}. Marginalizing over {Lambda}CDM cosmological models allowed by the Wilkinson Microwave Anisotropy Probe (WMAP7) results in a measurement of A{sub lens} 0.90 {+-} 0.19, indicating that the amplitude of matter fluctuations over the redshift range 0.5 {approx}< z {approx}< 5 probed by CMB lensing is in good agreement with predictions. We present the results of several consistency checks. These include a clear detection of the lensing signature in CMB maps filtered to have no overlap in Fourier space, as well as a 'curl' diagnostic that is consistent with the signal expected for {Lambda}CDM. We perform a detailed study of bias in the measurement due to noise, foregrounds, and other effects and determine that these contributions are relatively small compared to the statistical uncertainty in the measurement. We combine this lensing measurement with resultsmore » from WMAP7 to improve constraints on cosmological parameters when compared to those from WMAP7 alone: we find a factor of 3.9 improvement in the measurement of the spatial curvature of the universe, {Omega}{sub k} = -0.0014 {+-} 0.0172; a 10% improvement in the amplitude of matter fluctuations within {Lambda}CDM, {sigma}{sub 8} = 0.810 {+-} 0.026; and a 5% improvement in the dark energy equation of state, w = -1.04 {+-} 0.40. When compared with the measurement of w provided by the combination of WMAP7 and external constraints on the Hubble parameter, the addition of the lensing data improves the measurement of w by 15% to give w -1.087 {+-} 0.096.« less

Authors:
; ; ; ;  [1]; ; ; ; ; ; ; ;  [2];  [3];  [4];  [5]; ;  [6];  [7];  [8] more »; « less
  1. Department of Physics, McGill University, 3600 Rue University, Montreal, Quebec H3A 2T8 (Canada)
  2. Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)
  3. Berkeley Center for Cosmological Physics, Department of Physics, University of California, and Lawrence Berkeley National Labs, Berkeley, CA 94720 (United States)
  4. University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)
  5. NIST Quantum Devices Group, 325 Broadway Mailcode 817.03, Boulder, CO 80305 (United States)
  6. Department of Physics, University of California, Berkeley, CA 94720 (United States)
  7. Department of Astrophysical and Planetary Sciences and Department of Physics, University of Colorado, Boulder, CO 80309 (United States)
  8. Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States)
Publication Date:
OSTI Identifier:
22092371
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 756; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; ASTROPHYSICS; BACKGROUND RADIATION; COSMOLOGICAL CONSTANT; COSMOLOGICAL MODELS; COSMOLOGY; EQUATIONS OF STATE; FLUCTUATIONS; GRAVITATIONAL LENSES; NONLUMINOUS MATTER; RED SHIFT; RELICT RADIATION; TELESCOPES; UNIVERSE

Citation Formats

Van Engelen, A., De Haan, T., Dobbs, M. A., Dudley, J., Holder, G. P., Keisler, R., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Crawford, T. M., Crites, A. T., Hoover, S., Zahn, O., Aird, K. A., Cho, H. M., George, E. M., Holzapfel, W. L., Halverson, N. W., Hou, Z., and and others. A MEASUREMENT OF GRAVITATIONAL LENSING OF THE MICROWAVE BACKGROUND USING SOUTH POLE TELESCOPE DATA. United States: N. p., 2012. Web. doi:10.1088/0004-637X/756/2/142.
Van Engelen, A., De Haan, T., Dobbs, M. A., Dudley, J., Holder, G. P., Keisler, R., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Crawford, T. M., Crites, A. T., Hoover, S., Zahn, O., Aird, K. A., Cho, H. M., George, E. M., Holzapfel, W. L., Halverson, N. W., Hou, Z., & and others. A MEASUREMENT OF GRAVITATIONAL LENSING OF THE MICROWAVE BACKGROUND USING SOUTH POLE TELESCOPE DATA. United States. doi:10.1088/0004-637X/756/2/142.
Van Engelen, A., De Haan, T., Dobbs, M. A., Dudley, J., Holder, G. P., Keisler, R., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Crawford, T. M., Crites, A. T., Hoover, S., Zahn, O., Aird, K. A., Cho, H. M., George, E. M., Holzapfel, W. L., Halverson, N. W., Hou, Z., and and others. Mon . "A MEASUREMENT OF GRAVITATIONAL LENSING OF THE MICROWAVE BACKGROUND USING SOUTH POLE TELESCOPE DATA". United States. doi:10.1088/0004-637X/756/2/142.
@article{osti_22092371,
title = {A MEASUREMENT OF GRAVITATIONAL LENSING OF THE MICROWAVE BACKGROUND USING SOUTH POLE TELESCOPE DATA},
author = {Van Engelen, A. and De Haan, T. and Dobbs, M. A. and Dudley, J. and Holder, G. P. and Keisler, R. and Benson, B. A. and Bleem, L. E. and Carlstrom, J. E. and Chang, C. L. and Crawford, T. M. and Crites, A. T. and Hoover, S. and Zahn, O. and Aird, K. A. and Cho, H. M. and George, E. M. and Holzapfel, W. L. and Halverson, N. W. and Hou, Z. and and others},
abstractNote = {We use South Pole Telescope data from 2008 and 2009 to detect the non-Gaussian signature in the cosmic microwave background (CMB) produced by gravitational lensing and to measure the power spectrum of the projected gravitational potential. We constrain the ratio of the measured amplitude of the lensing signal to that expected in a fiducial {Lambda}CDM cosmological model to be 0.86 {+-} 0.16, with no lensing disfavored at 6.3{sigma}. Marginalizing over {Lambda}CDM cosmological models allowed by the Wilkinson Microwave Anisotropy Probe (WMAP7) results in a measurement of A{sub lens} 0.90 {+-} 0.19, indicating that the amplitude of matter fluctuations over the redshift range 0.5 {approx}< z {approx}< 5 probed by CMB lensing is in good agreement with predictions. We present the results of several consistency checks. These include a clear detection of the lensing signature in CMB maps filtered to have no overlap in Fourier space, as well as a 'curl' diagnostic that is consistent with the signal expected for {Lambda}CDM. We perform a detailed study of bias in the measurement due to noise, foregrounds, and other effects and determine that these contributions are relatively small compared to the statistical uncertainty in the measurement. We combine this lensing measurement with results from WMAP7 to improve constraints on cosmological parameters when compared to those from WMAP7 alone: we find a factor of 3.9 improvement in the measurement of the spatial curvature of the universe, {Omega}{sub k} = -0.0014 {+-} 0.0172; a 10% improvement in the amplitude of matter fluctuations within {Lambda}CDM, {sigma}{sub 8} = 0.810 {+-} 0.026; and a 5% improvement in the dark energy equation of state, w = -1.04 {+-} 0.40. When compared with the measurement of w provided by the combination of WMAP7 and external constraints on the Hubble parameter, the addition of the lensing data improves the measurement of w by 15% to give w -1.087 {+-} 0.096.},
doi = {10.1088/0004-637X/756/2/142},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 756,
place = {United States},
year = {2012},
month = {9}
}