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تسجيل مستخدم جديدSource Counts Spanning Eight Decades of Flux Density at 1.4 GHz
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Brightness-weighted differential source counts $S^2 n(S)$ spanning the eight decades of flux density between $0.25,mumathrm{Jy}$ and 25 Jy at 1.4 GHz were measured from (1) the confusion brightness distribution in the MeerKAT DEEP2 image below $10,mumathrm{Jy}$, (2) counts of DEEP2 sources between $10,mumathrm{Jy}$ and $2.5,mathrm{mJy}$, and (3) counts of NVSS sources stronger than $2.5,mathrm{mJy}$. We present our DEEP2 catalog of $1.7 times 10^4$ discrete sources complete above $S = 10,mumathrm{Jy}$ over $Omega = 1.04,mathrm{deg}^2$. The brightness-weighted counts converge as $S^2 n(S) propto S^{1/2}$ below $S = 10,mumathrm{Jy}$, so $>99%$ of the $Delta T_mathrm{b} sim 0.06,mathrm{K}$ sky brightness produced by active galactic nuclei and $approx96%$ of the $Delta T_mathrm{b} sim 0.04,mathrm{K}$ added by star-forming galaxies has been resolved into sources with $S geq 0.25,mumathrm{Jy}$. The $Delta T_mathrm{b} approx 0.4,mathrm{K}$ excess brightness measured by ARCADE 2 cannot be produced by faint sources smaller than $approx 50,mathrm{kpc}$ if they cluster like galaxies.
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