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arXiv · 1508.05842

Observations of radio-quiet quasars at 10mas resolution by use of gravitational lensing

Neal Jackson·Amitpal S. Tagore·Carl Roberts·Dominique Sluse·Hannah Stacey·Hector Vives-Arias·Olaf Wucknitz·Filomena Volino
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Abstract

We present VLA detections of radio emission in four four-image gravitational lens systems with quasar sources: HS0810+2554, RXJ0911+0511, HE0435$-$1223 and SDSSJ0924+0219, and e-MERLIN observations of two of the systems. The first three are detected at a high level of significance, and SDSS J0924+0219 is detected. HS0810+2554 is resolved, allowing us for the first time to achieve 10-mas resolution of the source frame in the structure of a radio quiet quasar. The others are unresolved or marginally resolved. All four objects are among the faintest radio sources yet detected, with intrinsic flux densities in the range 1-5$μ$Jy; such radio objects, if unlensed, will only be observable routinely with the Square Kilometre Array. The observations of HS0810+2554, which is also detected with e-MERLIN, strongly suggest the presence of a mini-AGN, with a radio core and milliarcsecond scale jet. The flux densities of the lensed images in all but HE0435-1223 are consistent with smooth galaxy lens models without the requirement for smaller-scale substructure in the model, although some interesting anomalies are seen between optical and radio flux densities. These are probably due to microlensing effects in the optical.

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Neal Jackson, Amitpal S. Tagore, Carl Roberts, Dominique Sluse, Hannah Stacey, Hector Vives-Arias, Olaf Wucknitz, Filomena Volino. 2015-08-24. Observations of radio-quiet quasars at 10mas resolution by use of gravitational lensing. https://doi.org/10.1093/mnras%2Fstv1982

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