Gemini Imaging of Mid-IR Emission from the Nuclear Region of Centaurus A

Abstract

We present high spatial resolution mid-IR images of the nuclear region of NGC 5128 (Centaurus A). Images were obtained at 8.8 micron, N-band (10.4 micron), and 18.3 micron using the mid-IR imager/spectrometer T-ReCS on Gemini South. These images show a bright unresolved core surrounded by low-level extended emission. We place an upper limit to the size of the unresolved nucleus of 3.2 pc (0.19") at 8.8 micron and 3.5 pc (0.21") at 18.3 micron at the level of the FWHM. The most likely source of nuclear mid-IR emission is from a dusty torus and possibly dusty narrow line region with some contribution from synchrotron emission associated with the jet as well as relatively minor starburst activity. Clumpy tori models are presented which predict the mid-IR size of this torus to be no larger than 0.05" (0.85pc). Surrounding the nucleus is extensive low-level mid-IR emission. Previously observed by ISO and Spitzer, this paper presents to date the highest spatial resolution mid-IR images of this extended near nuclear structure. Much of the emission is coincident with Pa-alpha sources seen by HST implying emission from star forming areas, however evidence for jet induced star formation, synchrotron emission from the jet, a nuclear bar/ring, and an extended dusty narrow emission line region is also discussed.

22 pages, 6 figures, accepted by ApJ

References in corpus (7)

• 9.7 um Silicate Features in AGNs: New Insights into Unification Models
• Resolving the innermost parsec of Centaurus A at mid-infrared wavelengths
• The Infrared Emission from the Narrow Line Region
• The infrared jet in Centaurus A: multiwavelength constraints on emission mechanisms and particle acceleration
• High spatial resolution T-ReCS mid-infrared imaging of Luminous Infrared Galaxies
• Gemini Mid-IR Polarimetry of NGC1068: Polarized Structures Around the Nucleus
• Integral-field spectroscopy of Centaurus A nucleus

Cited by in corpus (21)

• The Infrared Nuclear Emission of Seyfert Galaxies on Parsec Scales: Testing the Clumpy Torus models
• Torus model properties of an ultra-hard X-ray selected sample of Seyfert galaxies
• Spitzer mid-infrared spectroscopy of compact symmetric objects: What powers radio-loud active galactic nuclei?
• Torus and polar dust dependence on AGN properties
• The dusty tori of nearby QSOs as constrained by high-resolution mid-IR observations
• Investigating the dusty torus of Seyfert galaxies using SOFIA/FORCAST photometry
• AGN torus detectability at sub-millimeter wavelengths: What to expect from ALMA continuum data
• TeV gamma-rays from UHECR interactions in AGN cores: Lessons from Centaurus A
• NuSTAR Observations of AGN with Low Observed X-ray to [OIII] Luminosity Ratios: Heavily Obscured AGN or Turned-Off AGN?
• SOFIA/FORCAST resolves 30 - 40 um extended dust emission in nearby active galactic nuclei
• Cooling timescale of dust tori in dying active galactic nuclei
• The outflow of gas from the Centaurus A circumnuclear disk: atomic spectral line maps from Herschel-PACS and APEX
• Polarized Mid-Infrared Synchrotron Emission in the Core of Cygnus A
• Finding of a population of active galactic nuclei showing a significant luminosity decline in the past $\sim 10^{3-4}$ yrs
• Subaru Spectroscopy and Spectral Modeling of Cygnus A
• Probing the roles of orientation and multi-scale gas distributions in shaping the obscuration of Active Galactic Nuclei through cosmic time
• JWST reveals the diversity of nuclear obscuring dust in nearby AGN: nuclear isolation of MIRI/MRS datacubes and continuum spectral fitting
• Modeling the unresolved NIR-MIR SEDs of local ($z<0.1$) QSOs
• Hot graphite dust in the inner regime of NGC 4151
• The properties of the obscuring material of an AGNs sample from mid-IR and X-ray simultaneous fitting
• CanariCam Mid-Infrared Drift Scanning: Improved Sensitivity and Spatial Resolution