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arXiv · 2103.08537

Resolving Complex Inner X-ray Structure of the Gravitationaly Lensed AGN MGB2016+112

Abstract

We use a Chandra X-ray observation of the gravitationally lensed system MGB2016+112 at z=3.273 to elucidate presence of at least two X-ray sources. We find that these sources are consistent with the VLBI components measured by \citet{Spingola19}, which are separated by $\sim 200$ pc. Their intrinsic 0.5 -- 7 keV source frame luminosities are 2.6$\times$10$^{43}$ and 4.2$\times$10$^{44}$ erg s$^{-1}$. Most likely this system contains a dual active galactic nucleus (AGN), but we possibly are detecting an AGN plus a pc-scale X-ray jet, the latter lying in a region at very high magnification. The quadruply lensed X-ray source is within $\pm$40 pc (1$\sigma$) of its VLBI counterpart. Using a gravitational lens as a telescope, and a novel statistical application, we have achieved unprecedented accuracy for measuring metric distances at such large redshifts in X-ray astronomy, which is tens of mas if the source is located close to the caustics, while it is of hundreds of mas if the source is in a region at lower amplification. The present demonstration of this approach has implications for future X-ray investigations of large numbers of lensed systems.

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Daniel Schwartz, Cristiana Spingola, Anna Barnacka. 2021-03-15. Resolving Complex Inner X-ray Structure of the Gravitationaly Lensed AGN MGB2016+112. https://doi.org/10.3847/1538-4357%2Fac0909

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