THE BURIED STARBURST IN THE INTERACTING GALAXY II Zw 096 AS REVEALED BY THE SPITZER SPACE TELESCOPE

Journal Article · Thu Jul 15 00:00:00 EDT 2010 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/140/1/63· OSTI ID:21443306

Inami, H; Armus, L; Surace, J A; Howell, J H; Petric, A; Haan, S; Murphy, E J; Stierwalt, S ^[1]; Mazzarella, J M; Chan, B ^[2]; Evans, A S ^[3]; Sanders, D B; Barnes, J E ^[4]; Vavilkin, T ^[5]; Iwasawa, K ^[6]; Appleton, P N; Frayer, D T ^[7]; Bothun, G ^[8]; Bridge, C R ^[9]; Charmandaris, V ^[10]

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1. Spitzer Science Center, California Institute of Technology, MS 220-6, Pasadena, CA 91125 (United States)
2. Infrared Processing and Analysis Center, California Institute of Technology, MS 100-22, Pasadena, CA 91125 (United States)
3. National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States)
4. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
5. Department of Physics and Astronomy, SUNY Stony Brook, Stony Brook, NY 11794 (United States)
6. ICREA and Universitat de Barcelona, MartI i Franques 1, Barcelona (Spain)
7. NASA Herschel Science Center, California Institute of Technology, MS 100-22, Pasadena, CA 91125 (United States)
8. Physics Department, University of Oregon, Eugene, OR 97402 (United States)
9. California Institute of Technology, MS 320-47, Pasadena, CA 91125 (United States)
10. Department of Physics, University of Crete, P.O. Box 2208, GR-71003, Heraklion (Greece)

An analysis of data from the Spitzer Space Telescope, Hubble Space Telescope, Chandra X-ray Observatory, and AKARI Infrared Astronomy Satellite is presented for the z = 0.036 merging galaxy system II Zw 096 (CGCG 448-020). Because II Zw 096 has an infrared luminosity of log(L{sub IR}/L{sub sun}) = 11.94, it is classified as a Luminous Infrared Galaxy (LIRG), and was observed as part of the Great Observatories All-sky LIRG Survey (GOALS). The Spitzer data suggest that 80% of the total infrared luminosity comes from an extremely compact, red source not associated with the nuclei of the merging galaxies. The Spitzer mid-infrared spectra indicate no high-ionization lines from a buried active galactic nucleus in this source. The strong detection of the 3.3 {mu}m and 6.2 {mu}m polycyclic aromatic hydrocarbon emission features in the AKARI and Spitzer spectra also implies that the energy source of II Zw 096 is a starburst. Based on Spitzer infrared imaging and AKARI near-infrared spectroscopy, the star formation rate is estimated to be 120 M{sub sun} yr{sup -1} and >45 M{sub sun} yr{sup -1}, respectively. Finally, the high-resolution B-, I-, and H-band images show many star clusters in the interacting system. The colors of these clusters suggest at least two populations-one with an age of 1-5 Myr and one with an age of 20-500 Myr, reddened by 0-2 mag of visual extinction. The masses of these clusters span a range between 10{sup 6} and 10{sup 8} M{sub sun}. This starburst source is reminiscent of the extranuclear starburst seen in NGC 4038/9 (the Antennae Galaxies) and Arp 299 but approximately an order of magnitude more luminous than the Antennae. The source is remarkable in that the off-nuclear infrared luminosity dominates the entire system.

• OSTI ID: 21443306
• Journal Information: Astronomical Journal (New York, N.Y. Online), Vol. 140, Issue 1; Other Information: DOI: 10.1088/0004-6256/140/1/63; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ABSORPTION SPECTROSCOPY
ANTENNAS
ASTRONOMY
DATA ANALYSIS
GALAXIES
IMAGES
INFRARED SPECTRA
IONIZATION
LUMINOSITY
MASS
POLYCYCLIC AROMATIC HYDROCARBONS
RESOLUTION
SATELLITES
STAR CLUSTERS
STARS
TELESCOPES
X RADIATION
AROMATICS
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
EQUIPMENT
HYDROCARBONS
IONIZING RADIATIONS
OPTICAL PROPERTIES
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
RADIATIONS
SPECTRA
SPECTROSCOPY