The chemical footprint of AGN feedback in the outflowing circumnuclear disk of NGC 1068

Abstract

In the nearby (D=14 Mpc) AGN-starburst composite galaxy NGC 1068, it has been found that the molecular gas in the Circum-nuclear Disk (CND) is outflowing, which is a manifestation of ongoing AGN feedback. The outflowing gas has a large spread of velocities, which likely drive different shock chemistry signatures at different locations in the CND. We perform a multi-line molecular study using two shock tracers, SiO and HNCO, with the aim to determine the gas properties traced by these two species, and explore the possibility of reconstructing the shock history in the CND. Five SiO transitions and three HNCO transitions were imaged at high resolution $0^{\prime \prime }.5-0^{\prime \prime }.8$ with the Atacama Large Millimeter/submillimeter Array (ALMA). We performed both LTE and non-LTE radiative transfer analysis coupled with Bayesian inference process in order to characterize the gas properties, such as molecular gas density and gas temperature. We found clear evidence of chemical differentiation between SiO and HNCO, with the SiO/HNCO ratio ranging from greater than one on the east of CND to lower than one on the west side. The non-LTE radiative transfer analysis coupled with Bayesian inference confirms that the gas traced by SiO has different densities - and possibly temperatures - than that traced by HNCO. We find that SiO traces gas affected by fast shocks while the gas traced by HNCO is either just affected by slow shocks or not shocked at all. A distinct differentiation between SiO and HNCO has been revealed in our observations and the further analysis of the gas properties traced by both species, which confirms the results from previous chemical modelings.

Accepted for publication in A&A

References in corpus (20)

• Molecular line emission in NGC1068 imaged with ALMA. I An AGN-driven outflow in the dense molecular gas
• A multi-transition HCN and HCO+ study of 12 nearby active galaxies: AGN versus SB environments
• The anatomy of the Orion B Giant Molecular Cloud: A local template for studies of nearby galaxies
• Parametrization of C-shocks. Evolution of the Sputtering of Grains
• Molecular line emission in NGC1068 imaged with ALMA: II. The chemistry of the dense molecular gas
• Shedding light on the formation of the pre-biotic molecule formamide with ASAI
• ALMA images the many faces of the NGC1068 torus and its surroundings
• Tracing shocks and photodissociation in the Galactic center region
• Molecular Line Emission as a Tool for Galaxy Observations (LEGO). I. HCN as a tracer of moderate gas densities in molecular clouds and galaxies
• Low Temperature Surface Formation of NH3 and HNCO: hydrogenation of nitrogen atoms in CO-rich interstellar ice analogues
• Multi-molecule ALMA observations towards the Seyfert 1 galaxy NGC 1097
• HCO mapping of the Horsehead : Tracing the illuminated dense molecular cloud surfaces
• CI and CO in nearby galaxy centers: the bright galaxies NGC1068 (M77), NGC2146, NGC3079, NGC4826 (M64), and NGC7469
• ALMA 0.02"-resolution observations reveal HCN-abundance-enhanced counter-rotating and outflowing dense molecular gas at the NGC 1068 nucleus
• ALMA imaging of C2H emission in the disk of NGC1068
• Molecular shock tracers in NGC 1068: SiO and HNCO
• The Distribution and Origin of C${}_2$H in NGC 253 from ALCHEMI
• Molecular transitions as probes of the physical conditions of extragalactic environments
• Spatially resolved star-formation relations of dense molecular gas in NGC 1068
• Tracing high density gas in M 82 and NGC 4038

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• Parabolic-like Trend in SiO Ratios throughout the Central Molecular Zone: Possible Signature of a Past Nuclear Activity in the Galactic Center
• Millimeter-wave CO and SiO Observations toward the Broad-velocity-width Molecular Feature CO 16.134-0.553: a Smith cloud scenario?