A blind estimation of the power spectrum of CMB anisotropy from WMAP

Abstract

Accurate measurements of angular power spectrum of Cosmic Microwave Background (CMB) radiation has lead to marked improvement in the estimates of different cosmological parameters. This has required removal of foreground contamination as well as detector noise bias with reliability and precision. We present the estimation of CMB angular power spectrum from the multi-frequency observations of WMAP using a novel {\em model-independent} method. The primary product of WMAP are the observations of CMB in 10 independent difference assemblies (DA) that have uncorrelated noise. Our method utilizes maximum information available within WMAP data by linearly combining all the DA maps to remove foregrounds and estimating the power spectrum from cross power spectra of clean maps with independent noise. We compute 24 cross power spectra which are the basis of the final power spectrum. The binned average power matches with WMAP team's published power spectrum closely. A small systematic difference at large multipoles is accounted for by the correction for the expected residual power from unresolved point sources. The correction is small and significantly tempered. Previous estimates have depended on foreground templates built using extraneous observational input. This is the first demonstration that the CMB angular spectrum can be reliably estimated with precision from a *self contained analysis* of the WMAP data.

4 pages, 3 figures, Matches version accepted to ApJ. Lett. Minor editing; Level of bias at low multipoles mentioned. Suppl. details at http://meghnad.iucaa.ernet.in/~tarun/sup0508383

References in corpus (4)

• CMB component separation by parameter estimation
• Statistical Isotropy of the Wilkinson Microwave Anisotropy Probe Data: A Bipolar Power Spectrum Analysis
• CMB and foregrounds in WMAP first year data
• CMB power spectrum estimation using noncircular beams

Cited by in corpus (42)

• A needlet ILC analysis of WMAP 7-year data: estimation of CMB temperature map and power spectrum
• The tensor-to-scalar ratio in punctuated inflation
• A re-analysis of the three-year WMAP temperature power spectrum and likelihood
• Exploring Cosmic Origins with CORE: B-mode Component Separation
• Testing Global Isotropy of Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Data: Temperature Analysis
• A needlet ILC analysis of WMAP 9-year polarisation data: CMB polarisation power spectra
• Low Variance at large scales of WMAP 9 year data
• Foreground Subtraction of Cosmic Microwave Background Maps using WI-FIT (Wavelet based hIgh resolution Fitting of Internal Templates)
• Testing Isotropy of Cosmic Microwave Background Radiation
• Parity Asymmetry in the CMBR Temperature Power Spectrum
• CMB anisotropy power spectrum using linear combinations of WMAP maps
• New estimates of the CMB angular power spectra from the WMAP 5 yrs low resolution data
• Signals of Statistical Anisotropy in WMAP Foreground-Cleaned Maps
• Performance forecasts for the primordial gravitational wave detection pipelines for AliCPT-1
• Measuring Statistical Isotropy of CMB Anisotropy
• Methods for pixel domain correction of EB leakage
• A comparison of CMB Angular Power Spectrum Estimators at Large Scales: the TT case
• Planar distribution of the galaxies in the Local Group: a statistical and dynamical analysis
• An Improved Diffuse Foreground Subtraction by ILC method: CMB Map and Angular Power Spectrum using Planck and WMAP Observations
• Stable indications of relic gravitational waves in Wilkinson Microwave Anisotropy Probe data and forecasts for the Planck mission
• A Global ILC Approach in Pixel Space over Large Angular Scales of the Sky using CMB Covariance Matrix
• Angular power spectrum of CMB anisotropy from WMAP
• Effect of Foregrounds on the CMBR Multipole Alignment
• CMB Polarization and Temperature Power Spectra Estimation using Linear Combination of WMAP 5-year Maps
• CMB power spectrum estimation with non-circular beam and incomplete sky coverage
• Testing the ABS method with the simulated Planck temperature maps
• Direct measurement of the angular power spectrum of cosmic microwave background temperature anisotropies in the WMAP Data
• An Unbiased Estimator of the Full-sky CMB Angular Power Spectrum at Large Scales using Neural Networks
• Forecast of foreground cleaning strategies for AliCPT-1
• Foreground Maps in WMAP frequency bands
• Testing synchrotron models and frequency resolution in BINGO 21 cm simulated maps using GNILC
• An Accurate Reconstruction of CMB E Mode Signal over Large Angular Scales using Prior Information of CMB Covariance Matrix in ILC Algorithm
• The power spectrum of the cosmic microwave background Kolmogorov maps: possible clue to correlation of voids
• Model Independent Foreground Power Spectrum Estimation using WMAP 5-year Data
• A Bayesian ILC method for CMB B-mode posterior estimation and reconstruction of primordial gravity wave signal
• Application of Genetic Algorithm to Estimate the Large Angular Scale Features of Cosmic Microwave Background
• On the Impact of Random Residual Calibration Error on the Gibbs ILC Estimates over Large Angular Scales
• Cosmology with CMB anisotropy
• A Partial-Sky Gibbs ILC Approach for the Estimation of CMB Posterior over Large Angular Scales of the Sky
• On the detection of point sources in Planck LFI 70 GHz CMB maps based on cleaned K-map
• `Standard' Cosmological model & beyond with CMB
• Cosmological quests in the CMB sky