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In this work, we report a radio galaxy with precessing jets, double-peaked emission lines and the presence of two compact radio components with a projected separation of ~6 parsec in Very Long Baseline Interferometry (VLBI) observations. The emission line peak separations could be suggesting the presence of a supermassive black hole binary (BBH) with a separation of 6.3 parsec, matching the VLBI results. The kinematic jet precession model applied to the jets of J1328+2751 indicates that if it is a BBH, the accretion disk of the primary black hole is not coplanar with the binary system orbit, making its jet precess under the effect of the torque produced by the secondary black hole. However, we find that the Bardeen-Petterson effect can also provide precession timescales compatible with the jet precession period inferred in this source. This source has previously been identified as a restarted double-double radio galaxy (DDRG). Our findings therefore have important ramifications for the nature of DDRGs in general.
Double-peaked [O III]5007, profiles in active galactic nuclei (AGNs) may provide evidence for the existence of dual AGNs, but a good diagnostic for selecting them is currently lacking. Starting from $sim$ 7000 active galaxies in SDSS DR7, we assemble
A central compact object (CCO, e.g. a black hole) with an accretion disk has been suggested as the common central engine of various astrophysical phenomena, such as gamma-ray bursts (GRBs), tidal disruption events (TDEs) and active galactic nuclei (A
We have performed a spectral decomposition to search for dual active galactic nuclei (DAGNs) in the Sloan Digital Sky Survey (SDSS) quasars with $z<0.25$. Potential DAGN candidates are searched by referencing velocity offsets and spectral shapes of d
The classical nova YZ Reticuli was discovered in July 2020. Shortly after this we commenced a sustained, highly time-sampled coverage of its subsequent rapid evolution with time-resolved spectroscopy from the Global Jet Watch observatories. Its H-alp
We present here the results from dual-frequency phase-referenced VLBI observations of the Seyfert galaxy KISSR1494, which exhibits double peaked emission lines in its SDSS spectrum. We detect a single radio component at 1.6 GHz, but not at 5 GHz impl