First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission

By C. Bennett, R. S. Hill, Gary F. Hinshaw, M. Nolta, N. Odegard, L. Page, David N. Spergel, J. Weiland, E. L. Wright, M. Halpern and 6 more. 2003

823 citations recorded by the source corpus.

The WMAP mission has mapped the full sky to determine the geometry, content, and evolution of the universe. Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the cosmic microwave background (CMB) from foreground emission, including diffuse Galactic emission and Galactic and extragalactic point sources. We define masks that excise regions of high foreground emission, so CMB analyses can be carried out with minimal foreground contamination. We also present maps and spectra of the individual emission components, leading to an improved understanding of Galactic astrophysical processes. The effectiveness of template fits to remove foreground emission from the WMAP data is also examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We use a Maximum Entropy Method to construct a model of the Galactic emission components. The observed total Galactic emission matches the model to <1% and the individual model components are accurate to a few percent. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (βs ∼ −2.5) near star-forming regions, especially in the plane, and steepest (βs ∼ −3) in the halo. This is consistent with a picture of relativistic cosmic ray electron generation in star-forming regions and diffusion and convection within the plane. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are WMAP is the result of a partnership between Princeton University and NASA’s Goddard Space Flight Center. Scientific guidance is provided by the WMAP Science Team. Code 685, Goddard Space Flight Center, Greenbelt, MD 20771 Science Systems and Applications, Inc. (SSAI), 10210 Greenbelt Road, Suite 600 Lanham, Maryland 20706 Dept. of Physics, Jadwin Hall, Princeton, NJ 08544 Dept of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 UCLA Astronomy, PO Box 951562, Los Angeles, CA 90095-1562 Dept. of Physics and Astronomy, University of British Columbia, Vancouver, BC Canada V6T 1Z1 National Research Council (NRC) Fellow Depts. of Astrophysics and Physics, EFI and CfCP, University of Chicago, Chicago, IL 60637 Dept. of Physics, Brown University, Providence, RI 02912

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/18fe4ef6bc100397f8f1be4e4e024f449da4e1e3

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Citations in the corpus

On Foreground Removal from the Wilkinson Microwave Anisotropy Probe Data by an Internal Linear Combination Method: Limitations and Implications (2004, positive): “The WMAP satellite observes the sky at five frequencies (23, 33, 41, 61 and 94 GHz), and using at least in part this information the WMAP team have applied three different methods for removing, constraining, or describing the foregrounds (Bennett et al. 2003b).”
The SAURON project – VII. Integral-field absorption and emission-line kinematics of 24 spiral galaxy bulges (2006, neutral): “5 H 0 = 71 km s−1 Mpc−1 (Bennett et al. 2003).”
Simultaneous Planck, Swift, and Fermi observations of X-ray and γ-ray selected blazars (2011, neutral): “Figure 1 plots the Planck flux density at 44 GHz presented in this paper versus the WMAP flux density at 41 GHz from the WMAP point source catalogs (Bennett et al. 2003; Wright et al. 2009a).”
Non-Gaussian signatures in the temperature fluctuation observed by the Wilkinson Microwave Anisotropy Probe (2003, neutral): “Bennett et al. (2003b) estimate that the residual Galactic contamination after the template correction is 2.2, 0.8 and <0.4 per cent of the CMB power in Q, V and W bands, respectively, when the less conservative Kp2 mask is applied.”
The Australia Telescope 20 GHz Survey: the source catalogue (2009, neutral): “The WMAP Point Source Catalogue constructed from the 5 yr maps contains 390 sources (Wright et al. 2009), compared to 323 and 208 sources found in the previous 3 yr and 1 yr maps respectively (Bennett et al. 2003; Hinshaw et al. 2007).”
The Wisconsin Hα Mapper Northern Sky Survey (2001, neutral): “…of the WIM is important not only for improving the picture of the ISM and the interaction among its components, but also for understanding the nature of the foreground gas through which all extragalactic and cosmological observations are made (e.g., Lagache et al. 2000; Bennett et al. 2003).”
Asymmetries in the Cosmic Microwave Background Anisotropy Field (2004, positive): “In recent months much interest has focused on the question of the lack of large-scale power in the WMAP3 (Bennett et al. 2003a) first-year data sets (e.g., Efstathiou 2003a, b; Efstathiou 2004; Spergel et al. 2003; Tegmark, de Oliveira-Costa, & Hamilton 2003).”
SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP ) OBSERVATIONS: ARE THERE COSMIC MICROWAVE BACKGROUND ANOMALIES? (2010, neutral): “When WMAP data were first released in 2003, an image of the full sky was presented in Galactic coordinates, centered on the Galactic center (Bennett et al. 2003b).”
CMB and SZ effect separation with constrained Internal Linear Combinations (2010, neutral): “…for foreground emission, has been extensively used in the analysis of the maps obtained by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite to extract a CMB map (Bennett et al. 2003; Eriksen et al. 2004; Park, Park & Gott 2007; Kim, Naselsky & Christensen 2008; Delabrouille et al. 2009).”
A full sky, low foreground, high resolution CMB map from WMAP (2008, positive): “The ILC maps obtained by the WMAP team (denoted as WILC1, WILC3 and WILC5 hereafter, depending on whether they are obtained using one year, three year or five year data) are described in Bennett et al. (2003), Hinshaw et al. (2007), and Gold et al. (2008) respectively.”
The pre-launch Planck Sky Model: a model of sky emission at submillimetre to centimetre wavelengths (2012, positive): “2 (Reich & Reich, 1988; Davies, Watson, & Gutierrez, 1996; Platania et al., 2003; Bennett et al., 2003), with a general steepening of the spectrum towards high Galactic latitudes.”
Evidence of Vorticity and Shear at Large Angular Scales in the WMAP Data: A Violation of Cosmological Isotropy? (2005, neutral): “…first-year WMAP data6 in both raw and foreground template corrected forms (Bennett et al. 2003a,b) and three heavily processed maps derived to minimize the foreground contribution in a template independent way (WILC – Bennett et al. 2003b; LILC – Eriksen et al. 2004b; TOH – Tegmark et al. 2003).”
Model-independent Multivariable Gamma-Ray Burst Luminosity Indicator and Its Possible Cosmological Implications (2005, neutral): “Modern sophisticated observation techniques in distant SNe Ia (e.g. Riess et al. 1998; Schmidt et al. 1998; Perlmutter et al. 1999) and cosmic microwave background (CMB) fluctuations (e.g. Bennett et al. 2003; Spergel et al. 2003) have made great progress on modern precision cosmology.”