Foreground influence on primordial non-Gaussianity estimates: needlet analysis ofWMAP5-year data

2009/10/22 by P. Cabella, D. Pietrobon, M. Veneziani +5 · 1 citation
Physics and Astronomy · #Amplitude #Bispectrum #Cosmic background radiation #Cosmic microwave background #Cosmology #Cosmology and Gravitation Theories #Estimator #Galaxies: Formation, Evolution, Phenomena #Radio Astronomy Observations and Technology #Synchrotron #Thermal #astro-ph.CO

paper · pdf · doi:10.1111/j.1365-2966.2010.16542.x

Submitted to MNRAS

arxiv created 2009/10/22 · openalex publication_date 2010/03/01 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We constrain the amplitude of primordial non-Gaussianity in the cosmic microwave background data taking into account the presence of foreground residuals in the maps. We generalize the needlet bispectrum estimator marginalizing over the amplitudes of thermal dust, free–free and synchrotron templates. We apply our procedure to Wilkinson Microwave Anisotropy Probe 5-year data, finding fNL= 38 ± 47 (1σ), while the analysis without marginalization provides fNL= 35 ± 42. Splitting the marginalization over each foreground separately, we found that the estimates of fNL are positively cross-correlated of 17 and 12 per cent with the dust and synchrotron, respectively, while a negative cross-correlation of about −10 per cent is found for the free–free component.

Citations

• A new inflationary universe scenario: A possible solution of the horizon, flatness, homogeneity, isotropy and primordial monopole problems
• The needlets bispectrum
• Measuring Primordial Non‐Gaussianity in the Cosmic Microwave Background
• Cosmology for Grand Unified Theories with Radiatively Induced Symmetry Breaking
• Wavelets applied to cosmic microwave background maps: a multiresolution analysis for denoising
• Non-Gaussian features of primordial fluctuations in single field inflationary models
• Cross-correlation of the cosmic microwave background and radio galaxies in real, harmonic and wavelet spaces: detection of the integrated Sachs-Wolfe effect and dark energy constraints
• Non-Gaussianity from Inflation: Theory and Observations
• A high-significance detection of non-Gaussianity in theWMAP5-yr data using directional spherical wavelets
• Needlet detection of features in the WMAP CMB sky and the impact on anisotropies and hemispherical asymmetries
• High resolution foreground cleaned CMB map from WMAP
• Probing dark energy with steerable wavelets through correlation of WMAP and NVSS local morphological measures
• FIVE-YEARWILKINSON MICROWAVE ANISOTROPY PROBEOBSERVATIONS: COSMOLOGICAL INTERPRETATION
• FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: DATA PROCESSING, SKY MAPS, AND BASIC RESULTS

Cited by

• The primordial non-Gaussianity of local type (flocalNL) in the WMAP 5-year data: the length distribution of CMB skeleton