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Register a new userEvn, Merlin, and Vla Observations of Nrao530
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X.Y. Hong
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We present images of NRAO530 observed with the EVN (VLBI) at 5 GHz, the MERLIN at 1 .6 and 5 GHz, and the VLA at 5 and 8 GHz showing the complex morphology on scales from pc to kpc. The VLBI image shows a core-jet structure indicating a somehow oscillation trajectory on a scale of 30 mas, north to the strongest compact component (core). A core-jet structure extended to several hundreds mas at about P.A. -50 deg and a distant component located 11 arcsec west to the core are detected in both the MERLIN and the VLA observations. An arched structure of significant emission between the core and the distant component is also revealed in both the MERLIN image at 1.6 cm and the VLA images at 8.4 and 5 GHz. The core component shows a flat spectrum with alpha = -0.02 (S proportional to the frequency power -alpha) while alpha = 0.8 for the distant component. The steep spectrum of the distant component and the detection of the arched emission suggests that the western distant component is a lobe or a hot-spot powered by the nucleus of NRAO530. A patch of diffuse emission, 12 arcsec nearly east (P.A. = 70 deg) to the core component, is also observed with the VLA at 5 GHz, suggesting a presence of a counter lobe in the source.
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