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تسجيل مستخدم جديدSuperCLASS -- II: Photometric Redshifts and Characteristics of Spatially-Resolved $mu$Jy Radio Sources
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We present optical and near-infrared imaging covering a $sim$1.53 deg$^2$ region in the Super-Cluster Assisted Shear Survey (SuperCLASS) field, which aims to make the first robust weak lensing measurement at radio wavelengths. We derive photometric redshifts for $approx$176,000 sources down to $i^prime_{rm AB}sim24$ and present photometric redshifts for 1.4 GHz $e$-MERLIN and VLA detected radio sources found in the central 0.26 deg$^{2}$. We compile an initial catalog of 149 radio sources brighter than S$_{1.4}>75$ $mu$Jy and find their photometric redshifts span $0<z_{rm phot}<4$ with radio luminosities between $10^{21}-10^{25}$ W Hz$^{-1}$, with medians of $langle z rangle =0.55$ and $langle L_{1.4}rangle =1.9times10^{23}$ W Hz$^{-1}$ respectively. We find 95% of the uJy radio source sample (141/149) have SEDs best fit by star-forming templates while 5% (8/149) are better fit by AGN. Spectral indices are calculated for sources with radio observations from VLA and GMRT at 325 MHz, with an average spectral slope of $alpha=0.59pm0.04$. Using the full photometric redshift catalog we construct a density map at the redshift of the known galaxy clusters, $z=0.20pm0.08$. Four of the five clusters are prominently detected at $>7 sigma$ in the density map and we confirm the photometric redshifts are consistent with previously measured spectra from a few galaxies at the cluster centers.
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