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تسجيل مستخدم جديدVLA imaging of the XMM-LSS / VIDEO deep field at 1-2 GHz
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Modern radio telescopes are routinely reaching depths where normal starforming galaxies are the dominant observed population. Realising the potential of radio as a tracer of star formation and black hole activity over cosmic time involves achieving such depths over representative volumes, with radio forming part of a larger multiwavelength campaign. In pursuit of this we used the Karl G. Jansky Very Large Array (VLA) to image $sim$5 deg$^{2}$ of the VIDEO/XMM-LSS extragalactic deep field at 1--2 GHz. We achieve a median depth of 16 $mu$Jy beam$^{-1}$ with an angular resolution of 4.5arcsec. Comparisons with existing radio observations of XMM-LSS showcase the improved survey speed of the upgraded VLA: we cover 2.5 times the area and increase the depth by $sim$20% in 40% of the time. Direction-dependent calibration and wide-field imaging were required to suppress the error patterns from off-axis sources of even modest brightness. We derive a catalogue containing 5,762 sources from the final mosaic. Sub-band imaging provides in-band spectral indices for 3,458 (60%) sources, with the average spectrum becoming flatter than the canonical synchrotron slope below 1 mJy. Positional and flux-density accuracy of the observations, and the differential source counts are in excellent agreement with those of existing measurements. A public release of the images and catalogue accompanies this article.
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