High Spatial Resolution Imaging of Arp 220 from 3 - 25 microns

Abstract

Images of Arp 220 from 3.45 to 24.5 $\mu$m with 0.5'' resolution are presented which clearly separate the nucleus into at least two components. The western component is about three times more luminous than the eastern component, but the silicate absorption in the fainter, eastern component is roughly 50% greater than the absorption in the western component. Each component is marginally resolved. The two components seen at 24.5 $\mu$m are identified with the two radio components. The western source most likely coincides with the high extinction disk previously suggested to exist in Arp 220, while the eastern nucleus is identified with a faint highly reddened source seen in HST 2.2 $\mu$m NICMOS images. The two nuclei together account for essentially all of the measured 24.5 $\mu$m flux density. Two models are presented, both of which fit the observations. In one, the majority of the total luminosity is produced in an extended star formation region and in the other most of the luminosity is produced in the compact but extincted regions associated with the two nuclei seen at 24.5 $\mu$m. In both pictures, substantial luminosity at 100 $\mu$m emerges from a component having a diameter of 2--3'' ($\sim$1kpc).

LaTeX with AAS format, 3 postscript figures, ApJ, accepted

References in corpus (3)

• Rotating Nuclear Rings and Extreme Starbursts in Ultraluminous Galaxies
• What Powers Ultra-luminous IRAS Galaxies?
• NICMOS Imaging of the Nuclei of Arp 220

Cited by in corpus (56)

• Radiation Pressure Supported Starburst Disks and AGN Fueling
• Extragalactic Results from the Infrared Space Observatory
• The SCUBA-2 Cosmology Legacy Survey: ALMA resolves the rest-frame far-infrared emission of sub-millimeter galaxies
• High Resolution Mid-Infrared Imaging of Ultraluminous Infrared Galaxies
• VLBI Images of 49 Radio Supernovae in Arp 220
• Mid-infrared and optical spectroscopy of ultraluminous infrared galaxies: A comparison
• The Eddington Limit in Cosmic Rays: An Explanation for the Observed Faintness of Starbursting Galaxies
• SMA Imaging of CO(3-2) Line and 860 micron Continuum of Arp 220 : Tracing the Spatial Distribution of Luminosity
• Warm dust and aromatic bands as quantitative probes of star-formation activity
• Ultraluminous Infrared Galaxies
• CN and HNC Line Emission in IR Luminous Galaxies
• Black hole in the West Nucleus of Arp 220
• Theoretical modelling of the diffuse emission of gamma-rays from extreme regions of star formation: The case of Arp 220
• ALMA Resolves the Nuclear Disks of Arp 220
• The far-infrared spectrum of Arp 220
• Overluminous HNC Line Emission in Arp220, NGC4418 and Mrk231 - Global IR Pumping or XDRs?
• P-Cygni Profiles of Molecular Lines toward Arp 220 Nuclei
• High-Resolution Radio Continuum Measurements of the Nuclear Disks of Arp 220
• Low-mass X-ray binaries indicate a top-heavy stellar initial mass function in ultra compact dwarf galaxies
• Two Populations of Young Massive Star Clusters in Arp 220
• Mid-infrared spectral evidence for a luminous dust enshrouded source in Arp220
• APM 08279+5255: Keck Near- and Mid-IR High-Resolution Imaging
• Extreme dust disks in Arp 220 as revealed by ALMA
• HNC, HCN and CN in Seyfert galaxies
• Exploring the active galactic nucleus and starburst content of local ultraluminous infrared galaxies through 5-8 micron spectroscopy
• SMA CO(J=6-5) and 435 micron interferometric imaging of the nuclear region of Arp 220
• Spectral Energy Distributions of Dusty Galaxies
• Radio Emission from Young Supernovae and Supernova Remnants in Arp 299
• Modelling galaxy spectra in presence of interstellar dust. I. The model of ISM and the library of dusty SSPs
• Mid-Infrared Spectroscopy of Infrared Luminous Galaxies with Sub-Arcsecond Resolution
• Constraining dust formation in high-redshift young galaxies
• 8--13 micron spectroscopy of luminous and ultraluminous infrared galaxies
• Detection of extragalactic H3O+
• Chemically Distinct Nuclei and Outflowing Shocked Molecular Gas in Arp 220
• AGN feedback on molecular gas reservoirs in quasars at $z\sim$2.4
• The Effect of 53 micron IR Radiation on 18 cm OH Megamaser Emission
• High-resolution HNC 3-2 SMA observations of Arp220
• Feedback-Driven Evolution of the Far-Infrared Spectral Energy Distributions of Luminous and Ultraluminous Infrared Galaxies
• Arp220: extinction and merger-induced star formation
• Nuclear activity in nearby galaxies: Mid-infrared imaging with the VLT
• Modelling galaxy spectra in presence of interstellar dust. II. From the UV to the far infrared
• Gamma-ray bursts in normal and extreme star-forming galaxies
• NICMOS Observations of Interaction Triggered Star Formation in the Luminous Infrared Galaxy NGC 6090
• Sub-Arcsecond Mid-Infrared Observations of NGC 6240: Limitations of AGN-Starburst Power Diagnostics
• Far-Infrared Spectral Energy Distributions and Photometric Redshifts of Dusty Galaxies
• Photometric Properties of the Arp 220 Super Star Clusters
• The Subarcsecond Mid-Infrared View of Local Active Galactic Nuclei. IV. The L- and M-band Imaging Atlas
• Mid-IR and CO Observations of the IR/X-Ray Luminous Seyfert I Galaxy NGC985: The Making or Breaking of a ULIRG?
• Deeply Buried Nuclei in the Infrared-Luminous Galaxies NGC 4418 and Arp 220: I. ALMA Observations at $\lambda =$1.4-0.4 mm and Continuum Analysis
• Dust masses, compositions, and luminosities in the nuclear disks and the diffuse circumnuclear medium of Arp220
• Brackett-$\gamma$ as a Gold-standard Test of Star Formation Rates Derived from SED Fitting
• A Mid-Infrared and Far-Infrared View of Galaxies
• On the fate of gas in ultraluminous galaxies at low and high redshift
• The Rich JWST Spectrum of the Western Nucleus of Arp 220: Shocked Hot Core Chemistry Dominates the Inner Disk
• The Way of Water: ALMA resolves H2O emission lines in a strongly lensed dusty star-forming galaxy at z $\sim$ 3.1
• The processing of radiation by dust in galaxies