Star formation and gas flows in the centre of the NUGA galaxy NGC 1808 observed with SINFONI

Abstract

NGC 1808 is a nearby barred spiral galaxy which hosts young stellar clusters in a patchy circumnuclear ring with a radius of $\sim 240\mathrm{pc}$. In order to study the gaseous and stellar kinematics and the star formation properties of the clusters, we perform seeing-limited $H+K$-band near-infrared integral-field spectroscopy with SINFONI of the inner $\sim 600\mathrm{pc}$. From the $M_{\mathrm{BH}}-{\sigma }_{\ast }$ relation, we find a black hole mass of a few $10^7{M}_{\odot }$. We estimate the age of the young stellar clusters in the circumnuclear ring to be $\lesssim 10\mathrm{Myr}$. No age gradient along the ring is visible. However, the starburst age is comparable to the travel time along the ring, indicating that the clusters almost completed a full orbit along the ring during their life time. In the central $\sim 600\mathrm{pc}$, we find a hot molecular gas mass of $\sim 730M_{\odot }$ which, with standard conversion factors, corresponds to a large cold molecular gas reservoir of several $10^8{M}_{\odot }$, in accordance with CO measurements from the literature. The gaseous and stellar kinematics show several deviations from pure disc motion, including a circumnuclear disc and signs of a nuclear bar potential. In addition, we confirm streaming motions on $\sim 200\mathrm{pc}$ scale that have recently been detected in CO(1-0) emission. Due to our enhanced angular resolution of $<1\mathrm{arcsec}$, we find further streaming motion within the inner arcsecond, that have not been detected until now. Despite the flow of gas towards the centre, no signs for significant AGN activity are found. This raises the questions what determines whether the infalling gas will fuel an AGN or star formation.

19 pages, 19 figures, 3 tables; accepted for publication in Astronomy & Astrophysics

References in corpus (28)

• A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies: I. Galaxy Mergers & Quasar Activity
• HyperLEDA. III. The catalogue of extragalactic distances
• Molecular line emission in NGC1068 imaged with ALMA. I An AGN-driven outflow in the dense molecular gas
• A Close Look at Star Formation around Active Galactic Nuclei
• The Effects of Stellar Rotation. II. A Comprehensive Set of Starburst99 Models
• The SAURON project - VII. Integral-field absorption and emission-line kinematics of 24 spiral galaxy bulges
• The Star-Forming Torus and Stellar Dynamical Black Hole Mass in the Seyfert 1 Nucleus of NGC3227
• Mapping of the molecular gas inflow towards the Seyfert nucleus of NGC4051 using Gemini NIFS
• Fueling AGN II: Spatially Resolved Molecular Inflows and Outflows
• A SINFONI view of Galaxy Centers: Morphology and Kinematics of five Nuclear Star Formation Rings
• SINFONI adaptive optics integral field spectroscopy of the Circinus Galaxy
• A Connection between Star Formation in Nuclear Rings and their Host Galaxies
• AGN-Starburst connection in NGC7582: Gemini near-infrared spectrograph integral field unit observations
• Starburst-AGN mixing: II. Optically-selected active galaxies
• Probing the Physics of Narrow Line Regions in Active Galaxies II: The Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7)
• Near-IR Spectra of Red Supergiants and Giants. I- Models with Solar and with Mixing-Induced Surface Abundance Ratios
• Gemini/GMOS IFU stellar kinematics of the nuclear region of six nearby active galaxies
• Understanding the two-dimensional ionization structure in luminous infrared galaxies. A near-IR integral field spectroscopy perspective
• Feeding Versus Feedback in NGC1068 probed with Gemini NIFS. I. Excitation
• Ages and metallicities of circumnuclear star formation regions from Gemini IFU observations
• On the morphology of sigma-drop galaxies
• Mrk 609: resolving the circum-nuclear structure with near-infrared integral field spectroscopy
• Differences between CO- and calcium triplet-derived velocity dispersions in spiral galaxies: evidence for central star formation?
• ALMA backed NIR high resolution integral field spectroscopy of the NUGA galaxy NGC 1433
• A low-luminosity type-1 QSO sample: II. Tracing circumnuclear star formation in HE 1029-1831 with SINFONI
• Galaxy evolution across the optical emission-line diagnostic diagrams?
• Star clusters in a nuclear star-forming ring: The disappearing string of pearls
• A low-luminosity type-1 QSO sample: IV. Molecular gas contents and conditions of star formation in three nearby Seyfert galaxies

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