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The active galaxy MCG--6-30-15 has a 400 pc diameter stellar kinematically distinct core, counter-rotating with respect to the main body of the galaxy. Our previous high spatial resolution (0".1) H-band observations of this galaxy mapped the stellar kinematics and [Fe II] 1.64 {\mu}m gas dynamics though mainly restricted to the spatial region of the counter-rotating core. In this work we probe the stellar kinematics on a larger field-of-view and determine the ionised and molecular gas dynamics to study the formation of the counter-rotating core and the implications for AGN fuelling. We present integral field spectroscopy observations with SINFONI in the H and K-bands in the central 1.2 kpc and with VIMOS HR-blue in the central 4 kpc of the galaxy. Ionised gas outflows of v ~ 100 km/s are traced by the [Ca VIII] 2.32 {\mu}m coronal line and extend out to at least a radius of r ~ 140 pc. The molecular gas, traced by the H2 2.12 {\mu}m emission is also counter rotating with respect to the main body of the galaxy, indicating that the formation of the distinct core was associated with inflow of external gas into the centre of MCG--6-30-15. The molecular gas traces the available gas reservoir for AGN fuelling and is detected as close as r ~ 50 - 100 pc. External gas accretion is able to significantly replenish the fuelling reservoir suggesting that the event that formed the counter-rotating core was also the main mechanism providing gas for AGN fuelling., Comment: Accepted for publication in MNRAS

We extend our previous study of the cool gas responsible for the emission of O $\tiny \text{VII}$ X-ray lines in the cores of clusters and groups of galaxies. This is the coolest X-ray emitting phase and connects the 10 000 K H $\alpha$ emitting gas to the million degree phase, providing a useful tool to understand cooling in these objects. We study the location of the O $\tiny \text{VII}$ gas and its connection to the intermediate Fe $\tiny \text{XVII}$ and hotter O $\tiny \text{VIII}$ phases. We use high-resolution X-ray grating spectra of elliptical galaxies with strong Fe $\tiny \text{XVII}$ line emission and detect O $\tiny \text{VII}$ in 11 of 24 objects. Comparing the O $\tiny \text{VII}$ detection level and resonant scattering, which is sensitive to turbulence and temperature, suggests that O $\tiny \text{VII}$ is preferably found in cooler objects, where the Fe $\tiny \text{XVII}$ resonant line is suppressed due to resonant scattering, indicating subsonic turbulence. Although a larger sample of sources and further observations is needed to distinguish between effects from temperature and turbulence, our results are consistent with cooling being suppressed at high turbulence as predicted by models of active galactic nuclei feedback, gas sloshing and galactic mergers. In some objects, the O $\tiny \text{VII}$ resonant-to-forbidden line ratio is decreased by either resonant scattering or charge exchange boosting the forbidden line, as we show for NGC 4636. Charge exchange indicates interaction between neutral and ionized gas phases. The Perseus cluster also shows a high Fe $\tiny \text{XVII}$ forbidden-to-resonance line ratio, which can be explained with resonant scattering by low-turbulence cool gas in the line of sight., This work is based on observations obtained with XMM–Newton, an ESA science mission funded by ESA Member States and USA (NASA). We also acknowledge support from ERC Advanced Grant Feedback 340442 and new data from the awarded XMM–Newton proposal ID 0760870101. YYZ acknowledges support by the German BMWi through the Verbundforschung under grant 50OR1506.