3D spectroscopy of merger Seyfert galaxy Mrk 334: nuclear starburst, superwind and the circumnuclear cavern

Abstract

We are presenting new results on kinematics and structure of the Mrk 334 Seyfert galaxy. Panoramic (3D) spectroscopy is performed at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences using the integral-field Multi-Pupil Fiber Spectrograph (MPFS) and scanning Fabry-Pérot interferometer. The deep images have revealed that Mrk 334 is observed during the final stage of its merging with a massive companion. A possible mass ratio ranges from 1/5 to 1/3. The merger has triggered mass redistribution in the disc resulting in an intensification of nuclear activity and in a burst of star formation in the inner region of the galaxy. The circumnuclear starburst is so intense that its contribution to the gas ionization exceeds that contribution of the active galactic nuclei (AGN). We interpret the nuclear gas outflow with velocities of ∼200 km s −1 as a galactic superwind that accompanies the violent star formation. This suggestion is consistent with the asymmetric X-ray brightness distribution in Mrk 334. The trajectory of the fragments of the disrupted satellite in the vicinity of the main galaxy nucleus can be traced. In the galaxy disc, a cavern is found that is filled with a low-density ionized gas. We consider this region to be the place where the remnants of the companion have recently penetrated through the gaseous disc of the main galaxy.

Seyfert galaxies that are undergoing merging but appear non-interacting

“…The shells are the debris of this satellite and they mark the satellite's movement around Mrk 334. Brightness estimation for the tidal filaments yields a mass ratio of 1/5 to 1/3 for the interacting galaxies, which is close to the adopted boundary between minor and major merging (Smirnova & Moiseev 2010). According to HST observations (Deo, Grenshaw & Kraemer 2006), the nuclear dust morphology is chaotic, extensive star formation is taking place and the nuclear region shows two bright nuclei.…”

“…These observations aimed at a detailed investigation of the gas ionization properties as well as stellar and gas kinematics in the target galaxies, in order to find a possible mechanism of AGN fuelling related to jet/cloud interaction etc. The results for several individual galaxies were published (see, for instance, Ciroi 2001; Ciroi et al 2005; Radovich et al 2005; Smirnova, Moiseev & Afanasiev 2006; Smirnova & Moiseev 2010). In order to improve our knowledge about targets for which 3D spectroscopic data were available, a deep imaging observation programme was started.…”

Three-dimensional spectroscopy of local luminous compact blue galaxies: kinematic maps of a sample of 22 objects

“…0.95, −0.18 and −0.55 dex, respectively) to study the possible presence of AGN activity. UCM 0000 has been previously classified as an Sy1.8 galaxy by Véron‐Cetty & Véron (2006) and recently studied by Smirnova & Moiseev (2010). Fig.…”

Ongoing star formation in AGN host galaxy discs: a view from core-collapse supernovae

“…Adopting the characteristic radius of the galaxy R 25 ≈ 50 arcsec estimated from the fig. 4 in Smirnova & Moiseev (2010), the relative distance of the outer loop and arc is inferred to be ∼ 0.4–0.6.…”

“…Reichard et al (2009) recently reported a connection between AGN activity and lopsidedness of their host galaxies. An outer loop and an arc with blue colours were observed in Seyfert 1.8 galaxy Mark 334 at a radius r ∼ 20–30 arcsec from the centre (Smirnova & Moiseev 2010). The blue colours suggest the existence of young stellar populations (∼0.5–1 Gyr) that are formed in the interaction process.…”