We report the detection of fast (∼1000 km s −1 ), massive outflows of neutral gas observed -using the WSRT -as 21-cm H i absorption against the strong radio continuum of seven radio sources. The neutral outflows occur, in at least somes cases, at kpc distance from the nucleus, and they are most likely driven by the interactions between the expanding radio jets and the gaseous medium enshrouding the central regions. We estimate that the associated mass outflow rates are up to ∼50 M yr −1 , comparable (although at the lower end of the distribution) to the outflow rates found for starburst-driven superwinds in Ultra Luminous IR Galaxies (ULIRG). This suggests that massive, jet-driven outflows of neutral gas in radio-loud AGN can have as large an impact on the evolution of the host galaxies as the outflows associated with starbursts. A radio-loud phase of the AGN is likely a relatively common, albeit short, phase in the life of many (or even all) massive ellipticals. Jet-driven neutral outflows may represent one of the main feedback mechanisms in these galaxies.

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We present high‐quality long‐slit spectra for three nearby powerful radio galaxies – 3C 293, 3C 305 and PKS 1345+12. These were taken with the aim of characterizing the young stellar populations (YSP), and thereby investigating the evolution of the host galaxies, as well as the events that triggered the activity. Isochrone spectral synthesis modelling of the wide wavelength coverage spectra of nuclear and off‐nuclear continuum‐emitting regions have been used to estimate the ages, masses and luminosities of the YSP component, taking full account of reddening effects and potential contamination by activity‐related components. We find that the YSP make a substantial contribution to the continuum flux in the off‐nuclear regions on a radial scale of 1–20 kpc in all three objects. Moreover, in two objects we find evidence for reddened post‐starburst stellar populations in the near‐nuclear regions of the host galaxies. The YSP are relatively old (0.1–2 Gyr), massive (109 < MYSP < 2 × 1010 M⊙) and make up a large proportion (∼1–50 per cent) of the total stellar mass in the regions of the galaxies sampled by the observations. Overall, these results are consistent with the idea that the nuclear activity of active galactic nuclei in some radio galaxies is triggered by major gas‐rich mergers. Therefore, these radio galaxies form part of the subset of early‐type galaxies that is evolving most rapidly in the local Universe. Intriguingly, the results also suggest that the radio jets are triggered relatively late in the merger sequence, and that there is an evolutionary link between radio galaxies and luminous/ultraluminous infrared galaxies.

We carry out a systematic study of the X-ray emission from the active nuclei of the 0.02 < z < 0.7 2Jy sample, using Chandra and XMM-Newton observations. We combine our results with those from mid-IR, optical emission line and radio observations, and add them to those of the 3CRR sources. We show that the low-excitation objects in our samples show signs of radiatively inefficient accretion. We study the effect of the jet-related emission on the various luminosities, confirming that it is the main source of soft X-ray emission for our sources. We also find strong correlations between the accretion-related luminosities, and identify several sources whose optical classification is incompatible with their accretion properties. We derive the bolometric and jet kinetic luminosities for the samples and find a difference in the total Eddington rate between the low and high-excitation populations, with the former peaking at ∼ 1 per cent and the latter at ∼ 20 per cent Eddington. Our results are consistent with a simple Eddington switch when the effects of environment on radio luminosity and black hole mass calculations are considered. The apparent independence of jet kinetic power and radiative luminosity in the high-excitation population in our plots supports a model in which jet production and radiatively efficient accretion are not strongly correlated in high-excitation objects, though they have a common underlying mechanism.

Massive outflows driven by active galactic nuclei (AGN) are widely recognised to play a key role in the evolution of galaxies 1-4 , heating the ambient gas, expelling it from the nuclear regions, and thereby affecting the star formation histories of the galaxy bulges. It has been proposed that the powerful jets of relativistic particles launched by some AGN can both accelerate 5-7 and heat 8 the molecular gas, which often dominates the mass budgets of the outflows 5,9 . However, clear evidence for this mechanism in the form of detailed associations between the molecular gas kinematics and features in the radioemitting jets has been lacking. Here we show that the warm molecular hydrogen gas in the western radio lobe of the Seyfert galaxy IC5063 is moving at high velocities -up to +/-600 km s -1 -relative to the galaxy disk. This suggests that the molecules have been accelerated by fast shocks driven into the interstellar medium (ISM) by the expanding radio jets. These results demonstrate the general feasibility of accelerating molecular outflows in fast shocks driven by AGN. IC5063 (z=0.0113) is a massive early-type galaxy (M *~1 0 11 M  ) that hosts both a type II AGN and a powerful double-lobed radio source ( ! P 1.4GHz = 3 " 10 23 W Hz -1 ). The first signs of AGN-driven outflows in this object were provided by the detection of extended blue wings to the HI 21cm absorption feature and optical [OIII] emission lines at the site of the radio lobe 2.0 arcsec (0.45 kpc) to the west of its nucleus 10,11,12 . Subsequently, a blue wing was also detected in the CO(2-1) emission line profile of the integrated emission from the galaxy, providing evidence for molecular outflows 5 . However, the low spatial resolution of the mmwavelength CO observations of this and similar objects 5,6,7 prevented a direct link being established between the putative molecular outflows and the relativistic jets and lobes associated with the AGN.To overcome the resolution problem we have obtained deep, near-infrared long-slit spectroscopic observations of IC5063, taken with the slit aligned along the axis of the extended radio lobes and jets. The observations were made in good seeing conditions (FWHM=0.6 arcsec) and cover the H 2 1-0S(1)λ2.128µm and H 2 2-1S(2)λ2.154µm rotationalvibrational lines of molecular hydrogen, as well as the Brγλ2.166µm line emitted by the warm ionized gas at the same spatial locations in the galaxy. In Figure 1 we show a grey-scale representation of the long-slit spectrum, as well as line profiles extracted for three key regions