AGN feeding along a one-armed spiral in NGC 4593

A study using ALMA CO(2–1) observations

¹ European Southern Observatory (ESO), Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany
² Physics Department, Aeronautics Institute of Technology – ITA, Praça Marechal Eduardo Gomes, 50, São José dos Campos, 12228-900 São Paulo, Brazil
³ Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Plaza San Juan 1, 44001 Teruel, Spain
⁴ LERMA, Observatoire de Paris, Collége de France, PSL University, CNRS, Sorbonne University, Paris, France
⁵ INAF-Istituto di Astrofisica e Planetologia Spaziali, Via del Fosso del Cavaliere, 100, 00100 Roma, Italy
⁶ Instituto de Astrofísica de Canarias (IAC), E-38205 La Laguna, Tenerife, Spain
⁷ Universidad de La Laguna, Dpto. Astrofísica, E-38206 La Laguna, Tenerife, Spain
⁸ Instituto de Estudios Astrofísicos, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago, Chile
⁹ Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China
¹⁰ Department of Space, Earth & Environment, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
¹¹ National Astronomical Observatory of Japan, National Institutes of Natural Sciences (NINS), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
¹² Department of Astronomy, School of Science, Graduate University for Advanced Studies (SOKENDAI), Mitaka, Tokyo 181-8588, Japan
¹³ Instituto de Física Fundamental, CSIC, Calle Serrano 123, E-28006 Madrid, Spain
¹⁴ Departamento de Tecnologías Industriales, Facultad de Ingeniería, Universidad de Talca, Los Niches km 1, Curicó, Chile

^⋆ Corresponding author; khashayar@ita.br

Received: 19 June 2024
Accepted: 19 September 2024

Abstract

Context. We investigate active galactic nuclei (AGN) feeding through the molecular gas (CO(2−1) emission) properties of the local Seyfert 1 galaxy NGC 4593, using Atacama Large Millimeter Array (ALMA) observations and other multi-wavelength data.

Aims. Our study aims to understand the interplay between the AGN and the interstellar medium (ISM) in this galaxy, examining the role of the AGN in steering gas dynamics within its host galaxy, evaluating the energy injected into the ISM, and determining whether gas is inflowing or outflowing from the galaxy.

Methods. After reducing the ALMA CO(2−1) images, we employed two models, 3D-BAROLO and DISCFIT, to construct a disc model and fit its emission to the ALMA data. Additionally, we used photometric data to build a spectral energy distribution (SED) and apply the CIGALE code to derive key physical properties of the AGN and its host.

Results. Our analysis reveals a complex interplay within NGC 4593, including a clear rotational pattern, the influence of a non-axisymmetric bar potential, and a central molecular zone (CMZ)-like ring. We observe an outflow of CO(2−1) gas along the minor axis, at a distance of ∼220 pc from the nucleus. The total molecular gas mass is estimated to be 1 − 5 × 10⁸ M_⊙, with non-circular motions contributing 10%. Our SED analysis indicates an AGN fraction of 0.88 and a star formation rate (SFR) of 0.42 M_⊙ yr⁻¹.

Conclusions. These findings highlight the complex dynamics in the centre of NGC 4593, which are significantly influenced by the presence of the AGN. The overall physical properties of this system suggest that the AGN has a substantial impact on the evolution of NGC 4593.