Item

Abstract

We present an unprecedented view of the morphology and kinematics of the extended narrow-line region (ENLR) and molecular gas around the prototypical hyperluminous quasar 3C 273 (L _bol ∼ 10⁴⁷ erg s⁻¹ at z = 0.158) based on VLT-MUSE optical 3D spectroscopy and ALMA observations. We find the following: (1) the ENLR size of 12.1 ± 0.2 kpc implies a smooth continuation of the size─luminosity relation out to large radii or a much larger break radius as previously proposed. (2) The kinematically disturbed ionized gas with line splits reaching 1000 km s⁻¹ out to 6.1 ± 1.5 kpc is aligned along the jet axis. (3) The extreme line broadening on kiloparsec scales is caused by the spatial and spectral blending of many distinct gas clouds separated on subarcsecond scales by different line- of-sight (LOS) velocities. The ENLR velocity field combined with the known jet orientation rules out a simple scenario of a radiatively driven radial expansion of the outflow. Instead, we propose that a pressurized expanding hot gas cocoon created by the radio jet is impacting on an inclined gas disk, leading to transverse and/or backflow motion with respect to our LOS. The molecular gas morphology may be explained by either a density wave at the front of the outflow expanding along the jet direction as predicted by the positive feedback scenario or the cold gas may be trapped in a stellar overdensity caused by a recent merger event. Using 3C 273 as a template for observations of high-redshift hyperluminous quasars reveals that large-scale ENLRs and kiloparsec-scale outflows may often be missed, due to the brightness of the nuclei and the limited sensitivity of current near-IR instrumentation.