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Title: FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: LIKELIHOODS AND PARAMETERS FROM THE WMAP DATA

Abstract

This paper focuses on cosmological constraints derived from analysis of WMAP data alone. A simple {lambda}CDM cosmological model fits the five-year WMAP temperature and polarization data. The basic parameters of the model are consistent with the three-year data and now better constrained: {omega} {sub b} h {sup 2} = 0.02273 {+-} 0.00062, {omega} {sub c} h {sup 2} = 0.1099 {+-} 0.0062, {omega}{sub {lambda}} = 0.742 {+-} 0.030, n{sub s} = 0.963{sup +0.014} {sub -0.015}, {tau} = 0.087 {+-} 0.017, and {sigma}{sub 8} = 0.796 {+-} 0.036, with h = 0.719{sup +0.026} {sub -0.027}. With five years of polarization data, we have measured the optical depth to reionization, {tau}>0, at 5{sigma} significance. The redshift of an instantaneous reionization is constrained to be z {sub reion} = 11.0 {+-} 1.4 with 68% confidence. The 2{sigma} lower limit is z {sub reion} > 8.2, and the 3{sigma} limit is z {sub reion} > 6.7. This excludes a sudden reionization of the universe at z = 6 at more than 3.5{sigma} significance, suggesting that reionization was an extended process. Using two methods for polarized foreground cleaning we get consistent estimates for the optical depth, indicating an error due to the foreground treatment ofmore » {tau} {approx} 0.01. This cosmological model also fits small-scale cosmic microwave background (CMB) data, and a range of astronomical data measuring the expansion rate and clustering of matter in the universe. We find evidence for the first time in the CMB power spectrum for a nonzero cosmic neutrino background, or a background of relativistic species, with the standard three light neutrino species preferred over the best-fit {lambda}CDM model with N {sub eff} = 0 at >99.5% confidence, and N {sub eff} > 2.3(95%confidence limit (CL)) when varied. The five-year WMAP data improve the upper limit on the tensor-to-scalar ratio, r < 0.43(95%CL), for power-law models, and halve the limit on r for models with a running index, r < 0.58(95%CL). With longer integration we find no evidence for a running spectral index, with dn{sub s} /dln k = -0.037 {+-} 0.028, and find improved limits on isocurvature fluctuations. The current WMAP-only limit on the sum of the neutrino masses is {sigma}m {sub {nu}} < 1.3 eV(95%CL), which is robust, to within 10%, to a varying tensor amplitude, running spectral index, or dark energy equation of state.« less

Authors:
; ;  [1];  [2];  [3];  [4]; ; ;  [5]; ; ;  [6]; ;  [7];  [8];  [9];  [10];  [11]
  1. Department of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544-0708 (United States)
  2. Department of Astronomy, University of Texas, Austin, 2511 Speedway, RLM 15.306, Austin, TX 78712 (United States)
  3. Canadian Institute for Theoretical Astrophysics, 60 St. George Street, University of Toronto, Toronto, ON M5S 3H8 (Canada)
  4. Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544-1001 (United States)
  5. Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218-2686 (United States)
  6. Code 665, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  7. Adnet Systems, Inc., 7515 Mission Dr., Suite A100, Lanham, MD 20706 (United States)
  8. Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada)
  9. Columbia Astrophysics Laboratory, 550 W. 120th Street, Mail Code 5247, New York, NY 10027-6902 (United States)
  10. Departments of Astrophysics and Physics, KICP and EFI, University of Chicago, Chicago, IL 60637 (United States)
  11. Department of Physics, Brown University, 182 Hope Street, Providence, RI 02912-1843 (United States)
Publication Date:
OSTI Identifier:
21269306
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal, Supplement Series
Additional Journal Information:
Journal Volume: 180; Journal Issue: 2; Other Information: DOI: 10.1088/0067-0049/180/2/306; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0067-0049
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; ANISOTROPY; COSMIC NEUTRINOS; COSMOLOGICAL MODELS; COSMOLOGY; EQUATIONS OF STATE; ERRORS; EXPANSION; INDEXES; MASS; NONLUMINOUS MATTER; POLARIZATION; RED SHIFT; RELATIVISTIC RANGE; RELICT RADIATION; UNIVERSE

Citation Formats

Dunkley, J, Page, L, Jarosik, N, Komatsu, E, Nolta, M R, Spergel, D N, Larson, D, Bennett, C L, Gold, B, Hinshaw, G, Kogut, A, Wollack, E, Weiland, J L, Hill, R S, Halpern, M, Limon, M, Meyer, S S, Tucker, G S, and Wright, E. L. FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: LIKELIHOODS AND PARAMETERS FROM THE WMAP DATA. United States: N. p., 2009. Web. doi:10.1088/0067-0049/180/2/306; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Dunkley, J, Page, L, Jarosik, N, Komatsu, E, Nolta, M R, Spergel, D N, Larson, D, Bennett, C L, Gold, B, Hinshaw, G, Kogut, A, Wollack, E, Weiland, J L, Hill, R S, Halpern, M, Limon, M, Meyer, S S, Tucker, G S, & Wright, E. L. FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: LIKELIHOODS AND PARAMETERS FROM THE WMAP DATA. United States. https://doi.org/10.1088/0067-0049/180/2/306; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)
Dunkley, J, Page, L, Jarosik, N, Komatsu, E, Nolta, M R, Spergel, D N, Larson, D, Bennett, C L, Gold, B, Hinshaw, G, Kogut, A, Wollack, E, Weiland, J L, Hill, R S, Halpern, M, Limon, M, Meyer, S S, Tucker, G S, and Wright, E. L. Sun . "FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: LIKELIHOODS AND PARAMETERS FROM THE WMAP DATA". United States. https://doi.org/10.1088/0067-0049/180/2/306; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
@article{osti_21269306,
title = {FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: LIKELIHOODS AND PARAMETERS FROM THE WMAP DATA},
author = {Dunkley, J and Page, L and Jarosik, N and Komatsu, E and Nolta, M R and Spergel, D N and Larson, D and Bennett, C L and Gold, B and Hinshaw, G and Kogut, A and Wollack, E and Weiland, J L and Hill, R S and Halpern, M and Limon, M and Meyer, S S and Tucker, G S and Wright, E. L.},
abstractNote = {This paper focuses on cosmological constraints derived from analysis of WMAP data alone. A simple {lambda}CDM cosmological model fits the five-year WMAP temperature and polarization data. The basic parameters of the model are consistent with the three-year data and now better constrained: {omega} {sub b} h {sup 2} = 0.02273 {+-} 0.00062, {omega} {sub c} h {sup 2} = 0.1099 {+-} 0.0062, {omega}{sub {lambda}} = 0.742 {+-} 0.030, n{sub s} = 0.963{sup +0.014} {sub -0.015}, {tau} = 0.087 {+-} 0.017, and {sigma}{sub 8} = 0.796 {+-} 0.036, with h = 0.719{sup +0.026} {sub -0.027}. With five years of polarization data, we have measured the optical depth to reionization, {tau}>0, at 5{sigma} significance. The redshift of an instantaneous reionization is constrained to be z {sub reion} = 11.0 {+-} 1.4 with 68% confidence. The 2{sigma} lower limit is z {sub reion} > 8.2, and the 3{sigma} limit is z {sub reion} > 6.7. This excludes a sudden reionization of the universe at z = 6 at more than 3.5{sigma} significance, suggesting that reionization was an extended process. Using two methods for polarized foreground cleaning we get consistent estimates for the optical depth, indicating an error due to the foreground treatment of {tau} {approx} 0.01. This cosmological model also fits small-scale cosmic microwave background (CMB) data, and a range of astronomical data measuring the expansion rate and clustering of matter in the universe. We find evidence for the first time in the CMB power spectrum for a nonzero cosmic neutrino background, or a background of relativistic species, with the standard three light neutrino species preferred over the best-fit {lambda}CDM model with N {sub eff} = 0 at >99.5% confidence, and N {sub eff} > 2.3(95%confidence limit (CL)) when varied. The five-year WMAP data improve the upper limit on the tensor-to-scalar ratio, r < 0.43(95%CL), for power-law models, and halve the limit on r for models with a running index, r < 0.58(95%CL). With longer integration we find no evidence for a running spectral index, with dn{sub s} /dln k = -0.037 {+-} 0.028, and find improved limits on isocurvature fluctuations. The current WMAP-only limit on the sum of the neutrino masses is {sigma}m {sub {nu}} < 1.3 eV(95%CL), which is robust, to within 10%, to a varying tensor amplitude, running spectral index, or dark energy equation of state.},
doi = {10.1088/0067-0049/180/2/306; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)},
url = {https://www.osti.gov/biblio/21269306}, journal = {Astrophysical Journal, Supplement Series},
issn = {0067-0049},
number = 2,
volume = 180,
place = {United States},
year = {2009},
month = {2}
}