Testing the blast-wave AGN feedback scenario in MCG-03-58-007. Issue 2 (13th August 2019) - Sirressi, M
Abstract: We report the first Atacama large millimeter/submillimeter array observations of MCG-03-58-007, a local ( z = 0.03236 ± 0.00002, this work) AGN ($L_{\mathrm{ AGN}\mathrm{ }}\sim 10^{45}~\rm erg~s^{-1}$ ), hosting a powerful X-ray ultrafast ( v = 0.1 c ) outflow (UFO). The CO(1-0) line emission is observed across ∼18 kpc scales with a resolution of $\sim 1\, \rm kpc$ . About 78 per cent of the CO(1-0) luminosity traces a galaxy-size rotating disc. However, after subtracting the emission due to such rotating disc, we detect with a S/N = 20 a residual emission in the central ∼4 kpc. Such residuals may trace a low velocity ( v LOS = 170 km s −1 ) outflow. We compare the momentum rate ($\dot{P}$ ) and kinetic power ($\dot{E}$ ) of such putative molecular outflow with that of the X-ray UFO and find $\dot{P}_{\mathrm{ mol}}/\dot{P}_{\mathrm{ UFO}}\sim 0.4$ and $\dot{E}_{\mathrm{ mol}}/\dot{E}_{\mathrm{ UFO}}\sim 4\times 10^{-3}$ . This result is at odds with the energy-conserving scenario suggested by the large momentum boosts measured in some other molecular outflows. An alternative interpretation of the residual CO emission would be a compact rotating structure, distinct from the main disc, which would be a factor of ∼10–100 more extended and massive than typical circumnuclear discs revealed in Seyferts. In conclusion, in both scenarios, our results rule out the hypothesis of a momentum-boosted molecular outflow in this AGN, despite the presence of a powerful X-ray UFO.