摘要：We recently discovered that the luminous radio-quiet quasi-stellar objects (QSO) LBQS 0302–0019 atz = 3.286 is likely accompanied by an obscured AGN at 20 kpc projected distance, which we dubbedJil. It represents the tightest candidate system of an obscured and unobscured dual AGN atz > 3. To verify the dual AGN scenario, we obtained deepKsband (rest-frameVband) imaging with the VLT/HAWK-I+GRAAL instrument at 0.″4 resolution during science verification in January 2018. We detect the individual host galaxies of the QSO andJilwith estimated stellar masses of log(M⋆/M⊙) = 11.4 ± 0.5 and log(M⋆/M⊙) = 0.9 ± 0.5, respectively. Near-IR spectra obtained with Very Large Telescope-K-band Multi Object Spectrograph (VLT-KMOS) reveal a clear [OIII]λ5007 line detection at the location ofJilthat does not contribute significantly to theKsband flux. Both observations therefore corroborate the dual AGN scenario. A comparison to Illustris simulations suggests a parent halo mass of log(Mhalo/M⊙) = 13.2 ± 0.5 for this interacting galaxy system, corresponding to a massive dark matter halo at that epoch.
