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arXiv · 2003.05663

Searching for molecular gas in/outflows in the nuclear regions of five Seyfert galaxies

A. J. Domínguez-Fernández·A. Alonso-Herrero·S. García-Burillo·R. I. Davies·A. Usero·A. Labiano·N. A. Levenson·M. Pereira-Santaella·M. Imanishi·C. Ramos Almeida·D. Rigopoulou
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Abstract

AGN-driven outflows are believed to play an important role in regulating the growth of galaxies mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low and moderate luminosity Seyferts. To investigate this issue, we have obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58 Mpc) Seyfert galaxies. The resolution of approx. 0.3-0.8 arcsec (approx. 30-100 pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (approx. 100 pc) and up to radial distances of approx. 900 pc. We have detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring like morphologies. We derived cold molecular gas masses on nuclear (approx. 100 pc) and circumnuclear (approx. 650 pc) scales in the range from $10^6$ to $10^7$M$_{\odot}$ and from $10^7$ to $10^8$ $M_{\odot}$, respectively. In all of our galaxies the bulk of this gas is rotating in the plane of the galaxy. However, non-circular motions are also present. In NGC 4253, NGC 4388 and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the non-circular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas we need a detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc) as well as of the ionized gas kinematics and the ionization cone geometry.

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A. J. Domínguez-Fernández, A. Alonso-Herrero, S. García-Burillo, R. I. Davies, A. Usero, A. Labiano, N. A. Levenson, M. Pereira-Santaella, M. Imanishi, C. Ramos Almeida, D. Rigopoulou. 2020-03-12. Searching for molecular gas in/outflows in the nuclear regions of five Seyfert galaxies. https://doi.org/10.1051/0004-6361/201936961

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