Effect of component separation on the temperature distribution of the CMB
arXiv:astro-ph/0503039 · doi:10.1111/j.1365-2966.2006.10089.x
Abstract
We present a study of the effect of component separation on the recovered cosmic microwave background (CMB) temperature distribution, considering Gaussian and non-Gaussian input CMB maps. First, we extract the CMB component from simulated Planck data (in small patches of the sky) using the maximum entropy method (MEM), Wiener filter (WF) and a method based on the subtraction of foreground templates plus a linear combination of frequency channels (LCFC). We then apply a wavelet-based method to study the Gaussianity of the recovered CMB and compare it with the same analysis for the input map. When the original CMB map is Gaussian (and assuming that point sources have been removed), we find that none of the methods introduce non-Gaussianity (NG) in the CMB reconstruction. On the contrary, if the input CMB map is non-Gaussian, all the studied methods produce a reconstructed CMB with lower detections of NG than the original map. This effect is mainly due to the presence of instrumental noise. In this case, MEM tends to produce slightly higher non-Gaussian detections in the reconstructed map than WF whereas the detections are lower for the LCFC. We have also studied the effect of point sources in the MEM reconstruction. If no attempt to remove point sources is performed, they clearly contaminate the CMB reconstruction, introducing spurious NG. When the brightest point sources are removed from the data using the Mexican Hat Wavelet, the Gaussian character of the CMB is preserved. However, when analysing larger regions of the sky, the variance of our estimators will be appreciably reduced and, in this case, we expect the point source residuals to introduce spurious NG in the CMB. Thus, a careful subtraction (or masking) of point source emission is crucial when studying the Gaussianity of the CMB.
arXiv comment23 pages, 19 figures. Some new results added, including a new section about the role of foregrounds and instrumental noise. Accepted for publication in MNRAS
References in corpus (106)
- First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results
- A Line of Sight Approach to Cosmic Microwave Background Anisotropies
- MAXIMA-1: A Measurement of the Cosmic Microwave Background Anisotropy on angular scales of 10 arcminutes to 5 degrees
- Non-Gaussianity from Inflation: Theory and Observations
- First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission
- A measurement by BOOMERANG of multiple peaks in the angular power spectrum of the cosmic microwave background
- Nongaussian Isocurvature Perturbations from Inflation
- DASI First Results: A Measurement of the Cosmic Microwave Background Angular Power Spectrum
- Asymmetries in the CMB anisotropy field
- First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Tests of Gaussianity
- Second-Order Cosmological Perturbations from Inflation
- A high resolution foreground cleaned CMB map from WMAP
- Extrapolation of Galactic Dust Emission at 100 Microns to CMBR Frequencies Using FIRAS
- Detection of non-Gaussianity in the WMAP 1-year data using spherical wavelets
- Is the low-l microwave background cosmic?
- High Resolution Observations of the CMB Power Spectrum with ACBAR
- The Anisotropy of the Microwave Background to l = 3500: Deep Field Observations with the Cosmic Background Imager
- A method for subtracting foregrounds from multi-frequency CMB sky maps
- Multipole Vectors--a new representation of the CMB sky and evidence for statistical anisotropy or non-Gaussianity at 2<=l<=8
- Non-Gaussianity in multi-field inflation
- On Foreground Removal from the Wilkinson Microwave Anisotropy Probe Data by an Internal Linear Combination Method: Limitations and Implications
- Predictions for high-frequency radio surveys of extragalactic sources
- Extragalactic Source Counts and Contributions to the Anisotropies of the Cosmic Microwave Background. Predictions for the Planck Surveyor mission
- Observational Constraints on Cosmic String Production During Brane Inflation
- Multi-Detector Multi-Component spectral matching and applications for CMB data analysis
- The Cosmic Microwave Background Anisotropy Power Spectrum measured by Archeops
- Non-Gaussian Signatures in the Temperature Fluctuation Observed by the Wilkinson Microwave Anisotropy Probe
- Testing for Non-Gaussianity in the Wilkinson Microwave Anisotropy Probe Data: Minkowski Functionals and the Length of the Skeleton
- Foreground separation methods for satellite observations of the cosmic microwave background
- Asymmetries in the local curvature of the WMAP data
- Non-Gaussianity of the derived maps from the first-year WMAP data
- All-sky astrophysical component separation with Fast Independent Component Analysis (FastICA)
- Foregrounds and CMB Experiments: I. Semi-analytical estimates of contamination
- Evidence for non-Gaussianity in the COBE DMR Four Year Sky Maps
- Tests for Non-Gaussian Statistics in the DMR Four-Year Sky Maps
- Evidence for Scale-Scale Correlations in the Cosmic Microwave Background Radiation
- Towards a model of full-sky Galactic synchrotron intensity and linear polarisation: a re-analysis of the Parkes data
- Filtering techniques for the detection of Sunyaev-Zel'dovich clusters in multifrequency CMB maps
- Estimating non-gaussianity in the microwave background
- A high-significance detection of non-Gaussianity in the WMAP 1-year data using directional spherical wavelets
- Removing point sources from CMB maps
- The Hot and Cold Spots in the WMAP Data are Not Hot and Cold Enough
- Higher Criticism Statistic: Detecting and Identifying Non-Gaussianity in the WMAP First Year Data
- The CMB power spectrum out to l=1400 measured by the VSA
- The performance of spherical wavelets to detect non-Gaussianity in the CMB sky
- Neural networks and separation of Cosmic Microwave Background and astrophysical signals in sky maps
- Wavelets and WMAP non-Gaussianity
- Correspondence principle between spherical and Euclidean wavelets
- Evidence against or for topological defects in the BOOMERanG data ?
- A Bayesian approach to discrete object detection in astronomical datasets
- Isotropic Wavelets: a Powerful Tool to Extract Point Sources from CMB Maps
- Phase Correlations in Cosmic Microwave Background Temperature Maps
- Point Source Detection using the Spherical Mexican Hat Wavelet on simulated all-sky Planck maps
- Predictions on the angular power spectrum of clustered extragalactic point sources at CMB frequencies from flat and all--sky 2D-simulations
- Wavelet analysis and the detection of non-Gaussianity in the CMB
- CMB Polarization Experiments
- All-sky component separation for the Planck mission
- New non-Gaussian feature in COBE-DMR Four Year Maps
- 2-point anisotropies in WMAP and the Cosmic Quadrupole
- Testing the Gaussianity of the COBE-DMR data with spherical wavelets
- Optimal detection of sources on a homogeneous and isotropic background
- The Signature of a Correlation between Cosmic Ray Sources and Large Scale Structure
- Spherical Mexican Hat wavelet: an application to detect non-Gaussianity in the COBE-DMR maps
- Combining maximum-entropy and the mexican hat wavelet to reconstruct the microwave sky
- Scale-Adaptive filters for the detection/separation of compact sources
- Predicted Planck Extragalactic Point Source Catalogue
- COBE-DMR constraints on the nonlinear coupling parameter: a wavelet based method
- All-sky component separation in the presence of anisotropic noise and dust temperature variations
- The effect of point sources on satellite observations of the cosmic microwave background
- CMB power spectrum estimation and map reconstruction with the Expectation - Maximization algorithm
- The discriminating power of wavelets to detect non-Gaussianity in the CMB
- CMB and foregrounds in WMAP first year data
- Do wavelets really detect non-Gaussianity in the 4-year COBE data?
- Search for non-Gaussianity in pixel, harmonic and wavelet space: compared and combined
- The correlation of peaks in the microwave background
- 3-point temperature anisotropies in WMAP: Limits on CMB non-Gaussianities and non-linearities
- Phase Mapping as a Powerful Diagnostic of Primordial Non-Gaussianity
- Zeldovich flow on cosmic vacuum background: new exact nonlinear analytical solution
- Primordial non-Gaussianity: local curvature method and statistical significance of constraints on f_NL from WMAP data
- Genus Topology of the Cosmic Microwave Background from WMAP
- The Selection Function of SZ Cluster Surveys
- Astrophysical components separation of COBE-DMR 4yr data with FastICA
- Non-Gaussianity: Comparing wavelet and Fourier based methods
- A Bayesian non-parametric method to detect clusters in Planck data
- Reconstructing Sunyaev-Zeldovich clusters in future CMB experiments
- Cumulants as non-Gaussian qualifiers
- Constraining our Universe with X-ray & Optical Cluster Data
- Surveys of Galaxy Clusters with the Sunyaev Zel'dovich Effect
- Probing CMB Non-Gaussianity Using Local Curvature
- Comparing filters for the detection of point sources
- Filter design for the detection of compact sources based on the Neyman-Pearson detector
- Correlation of Excursion Sets for Non-Gaussian CMB Temperature Distributions
- Point source detection and extraction from simulated Planck TOD using optimal adaptive filters
- Geometrical estimators as a test of Gaussianity in the CMB
- Foreground separation using a flexible maximum-entropy algorithm: an application to COBE data
- Searching for non-gaussianity: Statistical tests
- The estimation of the SZ effects with unbiased multifilters
- An adaptive filter for the PLANCK Compact Source Catalogue construction
- Using the COBE/DMR data as a test-bed for normality assessments
- On the bispectrum of COBE and WMAP
- Scalar statistics on the sphere: application to the CMB
- Point sources in the MAP sky maps
- Goodness-of-Fit Tests to study the Gaussianity of the MAXIMA data
- A Bayesian approach to filter design: detection of compact sources
- Gaussianity of the CMB: Smooth Goodness of Fit Tests Applied to Interferometric Data
- Tests of Gaussianity
Cited by in corpus (4)
- Level Crossing Analysis of Cosmic Microwave Background Radiation: A method for detecting cosmic strings
- Statistical analysis of undetected point sources in cosmic microwave background maps
- Compact source detection in multi-channel microwave surveys: from SZ clusters to polarized sources
- Cosmic Microwave Background anisotropies: the power spectrum and beyond