Deep Radio Source Counts and Small Scale Fluctuations of the Microwave Background Radiation [chapter]

L. Danese, G. De Zotti, N. Mandolesi
1983 Early Evolution of the Universe and its Present Structure  
Source counts which now extend to surface densities of ^10^ sources/sr make possible a direct evaluation of the radio source contri bution to the small-scale fluctuations in the microwave background on scales larger than vLO f , at wavelengths =6 cm. Comprehensive radio spec tral data permit a straightforward and largely model-independent extrapo lation of the N(S) relation to shorter wavelengths. On the other hand, Peacock and Gull (1981, hereafter PG) have constructed a set of models which
more » ... of models which incorporate a wealth of additional data, such as local luminosity functions, luminosity/redshift distributions, luminosity-spectral index correlations; they can therefore be exploited to optimize the extrapola tions both to higher frequencies and to fainter flux densities. Only one of these models, however, namely No. 4, is consistent with the recent P(D) results (Wall _et aj.. 1982; Ledden e^ al. 1980) which provide infor mation on the areal density of sources at s'vLmJy; therefore, in the following we shall focus on it. (It is interesting to note, in passing, that P(D) counts do not reflect the faint end of counts at 408 MHz as it -3 -5 -6 0 12 3 log t> c (arcmin)
doi:10.1007/978-94-009-7220-9_33 fatcat:wm4hvox5rrazdlnvyiehieilde