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    Polarization in the cosmic microwave background
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    Abstract:
    Cosmic microwave background (CMB) studies underpin our understanding of the universe and its history. Until recently, we have relied principally on CMB temperature observations to build our standard cosmological model, but today the field forges ahead into its next frontier - CMB polarization anistropy. Polarization measurements will furnish fresh and independent information on the primordial density perturbations and cosmological parameters, and they offer the exciting potential to detect primordial gravity waves, constrain dark energy and measure the neutrino mass scale. I review the science and long-term goals of CMB polarization measurements and discuss current results and future observational projects. A vigorous program of ground-based, suborbital and space-based (e.g., WMAP and Planck [2008]) experiments is guiding us towards a future space mission dedicated to high precision polarization measurements.
    Keywords:
    CMB cold spot
    Observational cosmology
    Cosmic background radiation
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    CMB cold spot
    Cold spot
    Void (composites)
    Citations (35)
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    Cosmic background radiation
    Point source
    Background radiation
    Citations (0)
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    CMB cold spot
    Citations (1)
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    CMB cold spot
    Citations (34)
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    Citations (0)
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    Cosmic background radiation
    Observational cosmology
    Background radiation
    Citations (0)
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    CMB cold spot
    Cosmic background radiation
    Galactic plane
    Citations (0)
    This work is point of the preparation to the analysis of the PLANCK satellite data. The PLANCK satellite is an ESA mission which has been launched the 14th of may 2009 and is dedicaced to the measurement of the Cosmic Microwave Background (CMB) in temperature and polarization. The presence of diffuse Galactic polarized emissions disturb the measurement of the CMB anisotropies, in particular in polarization. Therefore a precise knowledge of these emissions is needed to obtain the level of accuracy required for PLANCK. In this context, we have developed and implemented a coherent 3D model of the two mains polarized Galactic emissions : synchrotron and thermal dust. We have compared these models to preexisting data: the 23 GHz band of the WMAP data, the 353 GHz Archeops data and the 408 MHz all-sky continuum survey. We extrapolate these models to the frequencies where the CMB dominates and we are able to estimate the contribution of polarized foreground emissions to the polarized CMB emission measured with PLANCK.
    Citations (0)