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Theoretical models and numerical simulations have established a framework of galaxy evolution in which galaxies merge and create dual supermassive black holes (with separations of one to ten kiloparsecs), which eventually sink into the centre of the merger remnant, emit gravitational waves and coalesce. The merger also triggers star formation and supermassive black hole growth, and gas outflows regulate the stellar content.sup.1-3. Although this theoretical picture is supported by recent observations of starburst-driven and supermassive black hole-driven outflows.sup.4-6, it remains unclear how these outflows interact with the interstellar medium. Furthermore, the relative contributions of star formation and black hole activity to galactic feedback remain unknown.sup.7-9. Here we report observations of dual outflows in the central region of the prototypical merger NGC 6240. We find a black-hole-driven outflow of [O iii] to the northeast and a starburst-driven outflow of H[alpha] to the northwest. The orientations and positions of the outflows allow us to isolate them spatially and study their properties independently. We estimate mass outflow rates of 10 and 75 solar masses per year for the H[alpha] bubble and the [O iii] cone, respectively. Their combined mass outflow is comparable to the star formation rate.sup.10, suggesting that negative feedback on star formation is occurring.Observations of NGC 6240 show two differently driven outflows of different gases with a combined outflow rate comparable to the star formation rate, suggesting possible negative feedback on star formation., Author(s): F. Müller-Sánchez [sup.1] , R. Nevin [sup.1] , J. M. Comerford [sup.1] , R. I. Davies [sup.2] , G. C. Privon [sup.3] [sup.4] , E. Treister [sup.3] Author Affiliations:(1) [...]

We apply an analytic Markov Chain Monte Carlo model to a sample of 18 active galactic nucleus (AGN)-driven biconical outflows that we identified from a sample of active galaxies with double-peaked narrow emission lines at z < 0.1 in the Sloan Digital Sky Survey. We find that 8 of 18 are best described as asymmetric bicones, 8 of 18 are nested bicones, and 2 of 18 are symmetric bicones. From the geometry and kinematics of the models, we find that these moderate-luminosity AGN outflows are large and energetic. The biconical outflows axes are randomly oriented with respect to the photometric major axis of the galaxy, implying a randomly oriented and clumpier torus to collimate the outflow, but the torus also allows some radiation to escape equatorially. We find that 16 of 18 (89 per cent) outflows are energetic enough to drive a two-staged feedback process in their host galaxies. All of these outflows geometrically intersect the photometric major axis of the galaxy, and 23 per cent of outflow host galaxies are significantly redder or have significantly lower specific star formation rates when compared to a matched sample of active galaxies. [ABSTRACT FROM AUTHOR]

COSMOS J100043.15+020637.2 is a merger remnant at z = 0.36 with two optical nuclei, NW and SE, offset by 500 mas (2.5 kpc). Prior studies suggest two competing scenarios for these nuclei: (1) SE is an active galactic nucleus (AGN) lost from NW due to a gravitational-wave recoil. (2) NW and SE each contain an AGN, signaling a gravitational-slingshot recoil or inspiralling AGNs. We present new images from the Very Large Array (VLA) at a frequency ν = 9.0 GHz and a FWHM resolution θ = 320 mas (1.6 kpc), and the Very Long Baseline Array (VLBA) at ν = 1.52 GHz and θ = 15 mas (75 pc). The VLA imaging is sensitive to emission driven by AGNs and/or star formation, while the VLBA imaging is sensitive only to AGN-driven emission. No radio emission is detected at these frequencies. Folding in prior results, we find: (a) The properties of SE and its adjacent X-ray feature resemble those of the Type 1 AGN in NGC 4151, albeit with a much higher narrow emission-line luminosity. (b) The properties of NW are consistent with it hosting a Compton-thick AGN that warms ambient dust, photoionizes narrow emission-line gas, and is free-free absorbed by that gas. Finding (a) is consistent with scenarios (a) and (b). Finding (b) weakens the case for scenario (a) and strengthens the case for scenario (b). Follow-up observations are suggested. [ABSTRACT FROM AUTHOR]

A correction to the article "Constraints on Two Active Galactic Nuclei in the Merger Remnant Cosmos," by J. M. Wrobel and colleagues, published in the April 2014 issue.