Taking snapshots of the jet-ISM interplay with ALMA
  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.
