The MAGNUM survey: positive feedback in the nuclear region of NGC 5643 suggested by MUSE^⋆

¹ INAF–Osservatorio Astrofisco di Arcetri, largo E. Fermi 5, 50127 Firenze, Italy
e-mail: gcresci@arcetri.astro.it
² Università degli Studi di Firenze, Dipartimento di Fisica e Astronomia, via G. Sansone 1, 50019 Sesto F.no, Firenze, Italy
³ Cavendish Laboratory, University of Cambridge, 19 J.J. Thomson Ave., Cambridge, UK
⁴ Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB2 1TN, UK
⁵ Dipartimento di Fisica e Astronomia, Universitá di Bologna, viale Berti-Pichat 6/2, 40127 Bologna, Italy
⁶ INAF–Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna, Italy
⁷ INAF–Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy
⁸ ETH Zürich, Institute for Astronomy, Department of Physics, Wolfgang-Pauli-Strasse 27, 8093 Zürich, Switzerland
⁹ Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
¹⁰ IRAM–Institut de RadioAstronomie Millimétrique, 300 rue de la Piscine, 38406 Saint Martin d’ Hères, France
¹¹ INAF–Osservatorio Astronomico di Roma, via Frascati 33, 00044 Monte Porzio Catone (RM), Italy
¹² Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006, Australia
¹³ Research Center for Space and Cosmic Evolution (RCSCE), Ehime University, Bunkyo-cho 2–5, Matsuyama, Ehime 790-8577, Japan
¹⁴ Max Planck Institut für extraterrestrische Physik, Postfach 1312, 85741 Garching, Germany
¹⁵ ESO, Alonso de Cordova 3107, Casilla 19, 19001 Santiago, Chile
¹⁶ Leibniz Institut für Astrophysik, An der Sternwarte 16, 14482 Potsdam, Germany

Received: 22 May 2015
Accepted: 18 August 2015

Abstract

We study the ionization and kinematics of the ionized gas in the nuclear region of the barred Seyfert 2 galaxy NGC 5643 using MUSE integral field observations in the framework of the Measuring Active Galactic Nuclei Under MUSE Microscope (MAGNUM) survey. The data were used to identify regions with different ionization conditions and to map the gas density and the dust extinction. We find evidence for a double-sided ionization cone, possibly collimated by a dusty structure surrounding the nucleus. At the center of the ionization cone, outflowing ionized gas is revealed as a blueshifted, asymmetric wing of the [OIII] emission line, up to projected velocity v₁₀ ~ −450 km s^-1. The outflow is also seen as a diffuse, low-luminosity radio and X-ray jet, with similar extension. The outflowing material points in the direction of two clumps characterized by prominent line emission with spectra typical of HII regions, located at the edge of the dust lane of the bar. We propose that the star formation in the clumps is due to positive feedback induced by gas compression by the nuclear outflow, providing the first candidate for outflow-induced star formation in a Seyfert-like, radio-quiet AGN. This suggests that positive feedback may be a relevant mechanism in shaping the black hole-host galaxy coevolution.