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As part of an on-going study of radio transients in Epoch 1 (2017-2019) of the Very Large Array Sky Survey (VLASS), we have discovered a sample of 0.2<z<3.2 active galactic nuclei (AGN) selected in the optical/infrared that have recently brightened dramatically in the radio. These sources would have previously been classified as radio-quiet based on upper limits from the Faint Images of the Radio Sky at Twenty-centimeters (FIRST; 1993-2011) survey; however, they are now consistent with radio-loud quasars. We present a quasi-simultaneous, multi-band (1-18 GHz) VLA follow-up campaign of our sample of AGN with extreme radio variability. We conclude that the radio properties are most consistent with AGN that have recently launched jets within the past few decades, potentially making them among the youngest radio AGN known.
The shape of bent, double-lobed radio sources requires a dense gaseous medium. Bent sources can therefore be used to identify galaxy clusters and characterize their evolutionary history. By combining radio observations from the Very Large Array Faint
The existence of a large population of Compton thick (CT, $N_{H}>10^{24} cm^{-2}$) AGN is a key ingredient of most Cosmic X-ray background synthesis models. However, direct identification of these sources, especially at high redshift, is difficult du
We present 190 galaxy cluster candidates (most at high redshift) based on galaxy overdensity measurements in the spitzer/IRAC imaging of the fields surrounding 646 bent, double-lobed radio sources drawn from the Clusters Occupied by Bent Radio AGN (C
In this data paper we present and characterise the multi-component radio sources identified in the VLA-COSMOS Large Project at 3 GHz (0.75 arcsec resolution, 2.3 {mu}Jy/beam rms), i.e. the radio sources which are composed of two or more radio blobs.T
Here we present new red sequence overdensity measurements for 77 fields in the high-$z$ Clusters Occupied by Bent Radio AGN (COBRA) survey, based on $r$- and $i$-band imaging taken with Lowell Observatorys Discovery Channel Telescope. We observe 38 C