NGC 6860, Mrk 915, and MCG -01-24-012: II. Inflowing and outflowing cold molecular gas and the connection with ionized gas in Seyfert galaxies
: De Oliveira, Bruno Dall'agnol; Storchi-Bergmann, Thaisa; Nagar, Neil; Garcia-Burillo, Santiago; Riffel, Rogemar A.; Wylezalek, Dominika; Kukreti, Pranav; Ramakrishnan, Venkatessh
Publisher: EDP Sciences
: 2026
Astronomy and Astrophysics
: A51
: 705
: 0004-6361
: 1432-0746
DOI: https://doi.org/10.1051/0004-6361/202555306
: https://doi.org/10.1051/0004-6361/202555306
: https://research.utu.fi/converis/portal/detail/Publication/509015694
We present a study of the cold molecular versus ionized gas distribution in three nearby Seyfert galaxies: NGC 6860, Mrk 915, and MCG -01-24-012. To constrain the cold molecular flux distribution at ∼0.5−0.8″ (∼150−400 pc) scales, we used data from the CO(2−1) emission line, obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). For the ionized gas, we used Hubble Space Telescope (HST) narrowband images, centered on the [O III]λλ4959,5007 emission lines. Within the inner kiloparsec of the three galaxies, we observe gaps in the CO emission in regions co-spatial with the [O III] flux distribution, similarly to what has recently been observed in other active galaxies. Of our original sample of 13 nearby active galactic nucleus (AGN) sources, 12 objects present the same trend. This indicates that CO molecules might be partially dissociated by AGN radiation or that there is a deficit of cold molecular gas on nuclear scales driven by ionized gas outflows and/or jets. If so, this represents a form of AGN feedback that is not captured when only outflow kinematic properties, such as mass outflow rates, are considered. We also discuss how part of the molecular gas might still be present in hotter H2 phases, as has already been observed in other objects.
Key words: ISM: jets and outflows / galaxies: active / galaxies: individual: NGC 6860 / galaxies: individual: Mrk 915 / galaxies: individual: MCG -01-24-012 / galaxies: Seyfert
:
This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES-Brasil, 88887.478902/2020-00, 88887.985730/2024-00). RAR acknowledges the support from Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq; Proj. 303450/2022-3, 403398/2023-1, & 441722/2023-7), Fundacao de Amparo a pesquisa do Estado do Rio Grande do Sul (FAPERGS; Proj. 21/2551-0002018-0), and CAPES (Proj. 88887.894973/2023-00). This paper makes use of the following ALMA data: ADS/JAO.ALMA#2018.1.00211.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The Legacy Surveys consist of three individual and complementary projects: the Dark Energy Camera Legacy Survey (DECaLS; Proposal ID #2014B-0404; PIs: David Schlegel and Arjun Dey), the Beijing-Arizona Sky Survey (BASS; NOAO Prop. ID #2015A-0801; PIs: Zhou Xu and Xiaohui Fan), and the Mayall z-band Legacy Survey (MzLS; Prop. ID #2016A-0453; PI: Arjun Dey). DECaLS, BASS and MzLS together include data obtained, respectively, at the Blanco telescope, Cerro Tololo Inter-American Observatory, NSF's NOIRLab; the Bok telescope, Steward Observatory, University of Arizona; and the Mayall telescope, Kitt Peak National Observatory, NOIRLab. Pipeline processing and analyzes of the data were supported by NOIRLab and the Lawrence Berkeley National Laboratory (LBNL). The Legacy Surveys project is honored to be permitted to conduct astronomical research on Iolkam Du'ag (Kitt Peak), a mountain with particular significance to the Tohono O'odham Nation. This research has made use of the NASA/IPAC Extragalactic Database, which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. This work used the color scheme from Wong (2011) in some of the plots to minimize confusion for colorblind viewers. Figure 8 was generated by combining the following software: FREECAD, LIBREOFFICE DRAW and MATPLOTLIB.
