Five-Year Wilkinson Microwave Anisotropy Probe Observations: Angular Power Spectra

We present the temperature and polarization angular power spectra of the cosmic microwave background derived from the first five years of Wilkinson Microwave Anisotropy Probe data. The five-year temperature spectrum is cosmic variance limited up to multipole ℓ = 530, and individual ℓ-modes have signal-to-noise ratio S/N >1 for ℓ < 920. The best-fitting six-parameter ΛCDM model has a reduced χ 2 for ℓ = 33–1000 of χ 2 /ν = 1.06, with a probability to exceed of 9.3%. There is now significantly improved data near the third peak which leads to improved cosmological constraints. The temperature-polarization correlation is seen with high significance. After accounting for foreground emission, the low-ℓ reionization feature in the EE power spectrum is preferred by Δχ 2 = 19.6 for optical depth τ = 0.089 by the EE data alone, and is now largely cosmic variance limited for ℓ = 2–6. There is no evidence for cosmic signal in the BB, TB, or EB spectra after accounting for foreground emission. We find that, when averaged over ℓ = 2–6, ℓ(ℓ + 1) C BB ℓ /(2π) < 0.15 μK 2 (95% CL).