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 Spingola et al. (2019), which are separated by ∼ 200 pc. Their intrinsic 0.5 -7 keV source frame luminosities are 2.6×10 43 and 4.2×10 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 ±40 pc (1σ) 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 magnification. The present demonstration of this approach has implications for future X-ray investigations of large numbers of lensed systems.