Hubble Space Telescope Imaging of the Circinus Galaxy

Abstract

We present an HST imaging study of the nearby (4 Mpc distant) Circinus galaxy, which contains the nearest type 2 Seyfert nucleus and prominent circumnuclear star formation. Images have been obtained in the [OIII]$\lambda$5007, H$\alpha$ and H${}_2$ v=1--0 S(1) emission lines, and in the green (5470 Å), red (8140 Å) and near infrared (2.04 and 2.15 $\mu$m) continua. An image in the [Fe II] $\lambda$1.644 $\mu$m line has been taken with a ground-based telescope. The [OIII] and H$\alpha$ images reveal the detailed structure of the complex of streamers and knots of high-excitation gas, which extends out of the galaxy disk. The morphology some 250 pc from the nucleus strongly suggests that the high-excitation gas is concentrated on the surface of a hollow cone with apex close to the nucleus. Such a structure may result through entrainment of dense gas from a circumnuclear torus in the galaxy disk by a low density, outflowing wind or jet. Within 40 pc of the nucleus, the high-excitation gas takes the form of a striking, filled V-shaped structure extending in the same direction as the larger scale high-excitation emission. This `V' can be described as an ionization cone, though a matter-bounded structure is also possible. The implied collimation of the ionizing photons or gaseous outflow must occur within 2 pc of the apex of the cone, presumed to be the location of the nucleus. The H$\alpha$ image shows a complex structure of HII regions, including the well known starburst ring of radius 150 - 270 pc. In addition, there is a more compact (40 pc radius), elliptical ring of HII regions around the `ionization cone'. We argue that this latter ring, which we call the nuclear ring, is intrinsically circular and located in the plane of the galaxy disk. Abstract truncated.

With 12 figures, to be published in the Astronomical Journal, September 2000 issue

Cited by in corpus (47)

• A Warped Accretion Disk and Wide Angle Outflow in the Inner Parsec of the Circinus Galaxy
• Bulgeless Giant Galaxies Challenge our Picture of Galaxy Formation by Hierarchical Clustering
• Resolving the complex structure of the dust torus in the active nucleus of the Circinus galaxy
• Determining Inclinations of Active Galactic Nuclei Via Their Narrow-Line Region Kinematics - I. Observational Results
• 3D Integral Field Observations of Ten Galactic Winds - I. Extended phase (>10 Myr) of mass/energy injection before the wind blows
• The black hole mass -- stellar velocity dispersion correlation: bulges versus pseudobulges
• AINUR: Atlas of Images of NUclear Rings
• The dusty torus in the Circinus galaxy: a dense disk and the torus funnel
• The subarcsecond mid-infrared view of local active galactic nuclei: I. The N- and Q-band imaging atlas
• The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus models
• Empirical diagnostics of the starburst-AGN connection
• The subarcsecond mid-infrared view of local active galactic nuclei: III. Polar dust emission
• Circumnuclear Multi-phase Gas in the Circinus Galaxy II: The Molecular and Atomic Obscuring Structures Revealed with ALMA
• N-band Imaging of Seyfert Nuclei and the MIR-X-ray correlation
• A Search for Very Extended Ionized Gas in Nearby Starburst and Active Galaxies
• Dissecting the active galactic nucleus in Circinus -- I. Peculiar mid-IR morphology explained by a dusty hollow cone
• Dissecting the active galactic nucleus in Circinus -- II. A thin dusty disc and a polar outflow on parsec scales
• A Chandra Study of the Circinus Galaxy Point-Source Population
• Mid-infrared, spatially-resolved spectroscopy of the nucleus of the Circinus galaxy
• Unveiling the central parsec region of an AGN: the Circinus nucleus in the near infrared with the VLT
• Morphology of the coronal line region in active galactic nuclei
• A Chandra Observation of the Circinus Galaxy
• The dusty heart of Circinus: I. Imaging the circumnuclear dust in N-band
• VLT diffraction-limited imaging at 11 and 18 micron of the nearest active galactic nuclei
• Physical conditions of molecular gas in the Circinus galaxy: Multi-J CO and CI 1-0 observations
• X-ray imaging of the Seyfert 2 galaxy Circinus with Chandra
• A Chandra view of the clumpy reflector at the heart of the Circinus galaxy
• Mapping the circumnuclear regions of the Circinus galaxy with the Imaging X-ray Polarimetry Explorer
• The Molecular Wind in the Nearest Seyfert Galaxy Circinus Revealed by ALMA
• AGN/starburst connection in action: the half million second RGS spectrum of NGC1365
• Shocks, Seyferts and the SNR connection: a Chandra observation of the Circinus galaxy
• Suzaku Observations of the Circinus galaxy
• Flux and spectral variations in the Circinus Galaxy
• Parsec-scale Imaging of the Radio-bubble Seyfert galaxy NGC 6764
• 12CO 4-3 and [CI] 1-0 at the centers of NGC 4945 and Circinus
• A Chandra and ALMA Study of X-ray-irradiated Gas in the Central ~100 pc of the Circinus Galaxy
• Thick turbulent gas disks with magnetocentrifugal winds in active galactic nuclei - Model infrared emission and optical polarization
• Circumnuclear Multi-phase Gas in Circinus Galaxy III: Structure of the Nuclear Ionized Gas
• ALMA imaging of the cold molecular and dusty disk in the type 2 active nucleus of the Circinus galaxy
• Discovery of ultra-compact nuclear rings in three spiral galaxies
• Detection of the H92alpha recombination line from the starbursts in the Circinus galaxy and NGC 1808
• Circumnuclear obscuration of the Circinus galaxy by a starburst-radiation supported wall
• Infrared Interferometry and AGNs: Parsec-scale Disks and Dusty Outflows
• The complexity of parsec-scaled dusty tori in AGN
• Embedded AGN and star formation in the central 80 pc of IC 3639
• The Spatial Variation of the 3micron Dust Features in Circinus
• X-ray and CO-Derived Column Densities in AGN: A Study of Obscuration Properties in CTAGN and Non-CTAGN