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arXiv · 0904.4498

GOALS: The Great Observatories All-Sky LIRG Survey

Abstract

The Great Observatories All-sky LIRG Survey (GOALS) combines data from NASA's Spitzer, Chandra, Hubble and GALEX observatories, together with ground-based data into a comprehensive imaging and spectroscopic survey of over 200 low redshift Luminous Infrared Galaxies (LIRGs). The LIRGs are a complete subset of the IRAS Revised Bright Galaxy Sample (RBGS). The LIRGs targeted in GOALS span the full range of nuclear spectral types defined via traditional optical line-ratio diagrams as well as interaction stages. They provide an unbiased picture of the processes responsible for enhanced infrared emission in galaxies in the local Universe. As an example of the analytic power of the multi-wavelength GOALS dataset, we present data for the interacting system VV 340 (IRAS F14547+2449). Between 80-95% of the total far-infrared emission (or about 5E11 solar luminosities) originates in VV 340 North. While the IRAC colors of VV 340 North and South are consistent with star-forming galaxies, both the Spitzer IRS and Chandra ACIS data indicate the presence of a buried AGN in VV 340 North. The GALEX far and near-UV fluxes imply a extremely large infrared "excess" (IRX) for the system (IR/FUV = 81) which is well above the correlation seen in starburst galaxies. Most of this excess is driven by VV 340 N, which alone has an IR excess of nearly 400. The VV 340 system seems to be comprised of two very different galaxies - an infrared luminous edge-on galaxy (VV 340 North) that dominates the long-wavelength emission from the system and which hosts a buried AGN, and a face-on starburst (VV 340 South) that dominates the short-wavelength emission.

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BibTeXRIS

L. Armus, J. M. Mazzarella, A. S. Evans, J. A. Surace, D. B. Sanders, K. Iwasawa, D. T. Frayer, J. H. Howell, B. Chan, A. O. Petric, T. Vavilkin, D. C. Kim, S. Haan, H. Inami, E. J. Murphy, P. N. Appleton, J. E. Barnes, G. Bothun, C. R. Bridge, V. Charmandaris, J. B. Jensen, L. J. Kewley, S. Lord, B. F. Madore, J. A. Marshall, J. E. Melbourne, J. Rich, S. Satyapal, B. Schulz, H. W. W. Spoon, E. Sturm, V. U, S. Veilleux, K. Xu. 2009-04-28. GOALS: The Great Observatories All-Sky LIRG Survey. https://doi.org/10.1086/600092

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