/ftp/cats/aliases/V//17V



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J/ApJ/405/498   Counts and spectral indices at 8.44GHz (Windhorst+, 1993)
The following files can be converted to FITS (extension .fit .fit.Z .fgz)
	table1a table1b
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Query from: http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=J/ApJ/405/498
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Beginning of ReadMe : J/ApJ/405/498 Counts and spectral indices at 8.44GHz (Windhorst+, 1993) ================================================================================ Microjansky source counts and spectral indices at 8.44 GHz WINDHORST R.A., FOMALONT E.B., PARTRIDGE R.B., LOWENTHAL J.D. <Astrophys. J. 405, 498 (1993)> =1993ApJ...405..498W (SIMBAD/NED Reference) ================================================================================ ADC_Keywords: Regional catalog; Radio sources Keywords: cosmic microwave background - galaxies: evolution - galaxies: starburst - radio continuum: galaxies - surveys Description: We used the VLA to make deep images of two 7x7' fields at 8.44 GHz with 10" resolution. With an rms noise of 3.2 and 5.1 microJy, respectively, in the two fields, we compiled a catalog of 82 sources. The normalized differential 8.44 GHz counts are similar to those at 1.41 and 4.86 GHz. All show a similarly steep submillijansky slope, which is only somewhat flatter than that expected for a nonevolving Euclidean population (gamma=2.5). Microjansky radio sources at 4.86 GHz have been identified with faint blue galaxies (18< V< 28 mag). We argue that their expected median redshift is about 0.5-0.75. Hence, cosmological evolution may be needed to explain the steep slope of the microjansky counts. The 8.44 GHz counts must converge with slope gamma<2.0 below S(8.44) 300 nJy, or they would exceed the available field galaxy counts down to V 28 mag, and they must permanently converge below S(8.44) 20 nJy, or their integrated sky brightness would distort the observed thermal cosmic background radiation spectrum at centimeter wavelengths. The estimated 31.5 GHz sky brightness from nanojansky to jansky levels is <36 microK (3sigma). Even if weak radio sources cluster on scales of degrees as faint galaxies do, their anisotropic contribution to the COBE DMR experiment (with 7deg FWHM-beam) would not exceed  1.2microK.

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