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

TL;DR

This paper presents detailed temperature and polarization power spectra of the CMB from 5 years of WMAP data, providing improved cosmological constraints and confirming the LambdaCDM model with high significance.

Contribution

First 5-year WMAP data analysis providing high-precision temperature and polarization spectra, refining cosmological parameters and confirming the LambdaCDM model.

Findings

Temperature spectrum is cosmic variance limited up to l=530.

High significance detection of temperature-polarization correlation (TE).

No evidence for B-mode polarization after foreground removal.

Abstract

We present the temperature and polarization angular power spectra of the cosmic microwave background (CMB) derived from the first 5 years of WMAP data. The 5-year temperature (TT) spectrum is cosmic variance limited up to multipole l=530, and individual l-modes have S/N>1 for l<920. The best fitting six-parameter LambdaCDM model has a reduced chi^2 for l=33-1000 of chi^2/nu=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 (TE) is seen with high significance. After accounting for foreground emission, the low-l reionization feature in the EE power spectrum is preferred by \Delta\chi^2=19.6 for optical depth tau=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/2\pi < 0.15 uK^2 (95% CL).