http://arxiv.org/abs/1507.02160
We measure the angular two-point correlation and angular power spectrum from the NRAO VLA Sky Survey (NVSS) of radio galaxies. Contrary to previous claims in the literature, we show that it is consistent with primordial Gaussianity on all angular scales and it is consistent with the best-fit cosmological model from the Planck analysis, as well as the redshift distribution obtained from the Combined EIS-NVSS Survey Of Radio Sources (CENSORS). Our analysis is based on an optimal estimation of the two-point correlation function and makes use of a new mask, which takes into account direction dependent effects of the observations, side lobe effects of bright sources and galactic foreground. We also use a lower flux threshold and take the cosmic radio dipole into account. The latter turns out to be an essential step in the analysis. This improved cosmological analysis of the NVSS stresses the importance of a flux calibration that is robust and stable on large angular scales for future radio continuum surveys.
S. Chen and D. Schwarz
Thu, 9 Jul 15
5/50
Comments: 11 pages, 15 figures
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