NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-25 T10:47:32 PDT
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For refcode 2009ApJ...704.1433M:
Retrieve 3164 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
2009ApJ...704.1433M A 31 GHz Survey of Low-Frequency Selected Radio Sources Mason, B. S.; Weintraub, L.; Sievers, J.; Bond, J. R.; Myers, S. T.; Pearson, T. J.; Readhead, A. C. S.; Shepherd, M. C. Abstract. The 100 m Robert C. Byrd Green Bank Telescope and the 40 m Owens Valley Radio Observatory telescope have been used to conduct a 31 GHz survey of 3165 known extragalactic radio sources over 143 deg^2^ of the sky. Target sources were selected from the NRAO VLA Sky Survey in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGNs) with 1.4 GHz flux densities of 3-10 mJy. The resulting 31 GHz catalogs are presented in full online. Using a maximum-likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4-31 GHz spectral indices of these sources, we find a mean 31-1.4 GHz flux ratio of 0.110 +/- 0.003 corresponding to a spectral index of {alpha} = -0.71 +/- 0.01 (S_{nu}_ vprop {nu}^{alpha}^) 9.0% +/- 0.8% of sources have {alpha} > - 0.5 and 1.2% +/- 0.2% have {alpha} > 0. By combining this spectral-index distribution with 1.4 GHz source counts, we predict 31 GHz source counts in the range 1 mJy < S_31_ < 4 mJy, N(>S_31_) = (16.7 +/- 1.7) deg^-2^(S_31_/1 mJy)^-0.80+/-0.07^. We also assess the contribution of mJy-level (S_1.4 GHz_ < 3.4 mJy) radio sources to the 31 GHz cosmic microwave background power spectrum, finding a mean power of {ell}({ell} + 1)C ^src^_{ell}_/(2{pi}) = 44 +/- 14 {mu}K^2^ and a 95% upper limit of 80 {mu}K^2^ at ell = 2500. Including an estimated contribution of 12 {mu}K^2^ from the population of sources responsible for the turn-up in counts below S_1.4 GHz_ = 1 mJy, this amounts to 21% +/- 7% of what is needed to explain the CBI high-{ell} excess signal, 275 +/- 63 {mu}K^2^. These results are consistent with other measurements of the 31 GHz point-source foreground. Key words: cosmic microwave background, cosmology: observations, galaxies: active, radio continuum: galaxies
Retrieve 3164 NED objects in this reference.
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