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We present an update of our on-going project to characterise the impact of radio jets on the ISM by tracing molecular gas at high spatial resolution using ALMA. The radio active galactic nuclei (AGN) studied show recently born radio jets. In this stage, the plasma jets can have the largest impact on the ISM, as also predicted by state-of-the-art simulations. The two targets have quite different ages, allowing us to get snapshots of the effects of radio jets as they grow. Interestingly, both also host powerful quasar emission. The largest mass outflow rate of molecular gas is found in a radio galaxy hosting a newly born radio jet emerging from an obscuring cocoon of gas and dust. Although the mass outflow rate is high (few hundred Msun/yr), the outflow is limited to the inner few hundred pc region. In a second object, the jet is larger (a few kpc) and is in a more advanced evolutionary phase. In this object, the distribution of the molecular gas is reminiscent of what is seen, on larger scales, in cool-core clusters hosting radio galaxies. Gas deviating from quiescent kinematics is not very prominent, limited only to the very inner region, and has a low mass outflow rate. Instead, on kpc scales, the radio lobes appear associated with depressions in the distribution of the molecular gas, suggesting they have broken out from the dense nuclear region. The AGN does not appear to be able at present to stop the star formation observed in this galaxy. These results suggest that the effects of the radio source start in the first phases by producing outflows which, however, tend to be limited to the kpc region. After that, the effects turn into producing large-scale bubbles which could, in the long term, prevent the surrounding gas from cooling. Our results characterise the effect of radio jets in different phases of their evolution, bridging the studies done for radio galaxies in clusters.
We have recently obtained polarimetric data at mm wavelengths with ALMA for the young systems DG Tau and CW Tau, for which the rotation properties of jet and disk have been investigated in previous high angular resolution studies. The motivation was
Supernovae are the most energetic stellar events and influence the interstellar medium by their gasdynamics and energetics. By this, both also affect the star formation positively and negatively. In this paper, we review the complexity of investigati
The Chandra X-ray observatory has discovered several dozen anomalously X-ray-bright jets associated with powerful quasars. A popular explanation for the X-ray flux from the knots in these jets is that relativistic synchrotron-emitting electrons inver
Current observations have shown that astrophysical jets reveal strong signs of radial structure. They suggest that the inner region of the jet, the jet spine, consists of a low-density, fast-moving gas, while the outer region of the jet consists of a
New high-resolution Very Long Baseline Interferometer observations of the prominent jet in the M87 radio galaxy show a persistent triple-ridge structure of the transverse 15-GHz profile with a previously unobserved ultra-narrow central ridge. This ra