Effects of Foreground Contamination on the Cosmic Microwave Background Anisotropy Measured by MAP

Abstract

We study the effects of diffuse Galactic, far-infrared extragalactic source, and radio point source emission on the cosmic microwave background (CMB) anisotropy data anticipated from the MAP experiment. We focus on the correlation function and genus statistics measured from mock MAP foreground-contaminated CMB anisotropy maps generated in a spatially-flat cosmological constant dominated cosmological model. Analyses of the simulated MAP data at 90 GHz (0.3 deg FWHM resolution smoothed) show that foreground effects on the correlation function are small compared with cosmic variance. However, the Galactic emission, even just from the region with |b| > 20 deg, significantly affects the topology of CMB anisotropy, causing a negative genus shift non-Gaussianity signal. Given the expected level of cosmic variance, this effect can be effectively reduced by subtracting existing Galactic foreground emission models from the observed data. IRAS and DIRBE far-infrared extragalactic sources have little effect on the CMB anisotropy. Radio point sources raise the amplitude of the correlation function considerably on scales below 0.5 deg. Removal of bright radio sources above a 5 σdetection limit effectively eliminates this effect. Radio sources also result in a positive genus curve asymmetry (significant at 2 σ) on 0.5 deg scales. Accurate radio point source data is essential for an unambiguous detection of CMB anisotropy non-Gaussianity on these scales. Non-Gaussianity of cosmological origin can be detected from the foreground-subtracted CMB anisotropy map at the 2 σlevel if the measured genus shift parameter |Δν| >= 0.02 (0.04) or if the measured genus asymmetry parameter |Δg| >= 0.03 (0.08) on a 0.3 (1.0) deg FWHM scale.

26 pages, 7 figures, Accepted for Publication in Astrophysical Journal (Some sentences and figures modified)

References in corpus (6)

• A High Spatial Resolution Analysis of the MAXIMA-1 Cosmic Microwave Background Anisotropy Data
• Cosmological implications of the MAXIMA-I high resolution Cosmic Microwave Background anisotropy measurement
• Binned Cosmic Microwave Background Anisotropy Power Spectra: Peak Location
• Gaussianity of Degree-Scale Cosmic Microwave Background Anisotropy Observations
• Concerning Parameter Estimation Using the Cosmic Microwave Background
• Correlation of the South Pole 94 data with 100microns and 408 MHz maps

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• Galactic Foregrounds in OVRO and UCSB South Pole 1994 Cosmic Microwave Background Anisotropy Data
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