Non-Gaussian Distribution and Clustering of Hot and Cold Pixels in the WMAP Five-Year Sky

Details Non-Gaussian Distribution and Clustering of Hot and Cold Pixels in the WMAP Five-Year Sky Non-Gaussian Distribution and Clustering of Hot and Cold Pixels in the WMAP Five-Year Sky

2009-06-11

arxiv.org/abs/0906.2190v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

16 pages, 14 figures, submitted to MNRAS

Scientific paper

We present measurements of the clustering of hot and cold patches in the microwave background sky as measured from the Wilkinson Microwave Anisotropy Probe (WMAP) five-year data. These measurements are compared with theoretical predictions which assume that the cosmological signal obeys Gaussian statistics. We find significant differences from the simplest Gaussian-based prediction. However, the measurements are sensitive to the fact that the noise is spatially inhomogeneous (e.g., because different parts of the sky were observed for different lengths of time). We show how to account for this spatial inhomogeneity when making predictions. Differences from the Gaussian-based expectation remain even after this more careful accounting of the noise. In particular, we note that hot and cold pixels cluster differently within the same temperature thresholds at few-degree scales. While these findings may indicate primordial non-Gaussianity, we discuss other plausible explanations for these discrepancies. In addition, we find some deviations from Gaussianity at sub-degree scales, especially in the W band, whose origin may be associated with extragalactic dust emission.

Affiliated with

Also associated with

No associations

Rating

Non-Gaussian Distribution and Clustering of Hot and Cold Pixels in the WMAP Five-Year Sky does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Non-Gaussian Distribution and Clustering of Hot and Cold Pixels in the WMAP Five-Year Sky, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-Gaussian Distribution and Clustering of Hot and Cold Pixels in the WMAP Five-Year Sky will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-517385