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We report the discovery of a small separation quasar pair (z=0.586, O=18.4, 19.2, sep. = 2.3 arcsec) associated with the radio source FIRST J164311.3+315618 (S_1400 = 120 mJy). The spectrum of the brighter quasar (A) has a much stronger narrow emission-line spectrum than the other (B), and also stronger Balmer lines relative to the continuum. The continuum ratio of the spectra is flat in the blue at about 2.1, but falls to 1.5 at longer wavelengths. A K image shows two unresolved sources with a flux ratio of 1.3. The different colors appear to result from the contribution of the host galaxy of B, which is evident from Ca II and high-order Balmer absorption lines indicative of a substantial young stellar population. New 3.6 cm VLA observations show that the compact radio source is coincident with quasar A (B is only marginally detected). We rule out the lensing hypothesis because the optical flux ratio is A/B = 1.2 to 2, while the radio flux ratio is A/B > 40, and conclude that this system is a binary. Moreover, the radio-loud quasar is a compact steep spectrum source. FIRST J164311.3+315618A, B is the lowest redshift and smallest separation binary quasar yet identified.
Lobe-dominated radio-loud (LD RL) quasars occupy a restricted domain in the 4D Eigenvector 1 (4DE1) parameter space which implies restricted geometry/physics/kinematics for this subclass compared to the radio-quiet (RQ) majority of quasars. We discus
We discuss 6 GHz JVLA observations covering a volume-limited sample of 178 low redshift ($0.2 < z < 0.3$) optically selected QSOs. Our 176 radio detections fall into two clear categories: (1) About $20$% are radio-loud QSOs (RLQs) having spectral lum
We investigate the clustering properties of 45441 radio-quiet quasars (RQQs) and 3493 radio-loud quasars (RLQs) drawn from a joint use of the Sloan Digital Sky Survey (SDSS) and Faint Images of the Radio Sky at 20 cm (FIRST) surveys in the range $0.3
Active galactic nuclei (AGNs) are known to cover an extremely broad range of radio luminosities and the spread of their radio-loudness is very large at any value of the Eddington ratio. This implies very diverse jet production efficiencies which can
Radio sources at the highest redshifts can provide unique information on the first massive galaxies and black holes, the densest primordial environments, and the epoch of reionization. The number of astronomical objects identified at z>6 has increase