GOALS Observations of Star Formation and AGN Activity in the Luminous Infrared Galaxy NGC 2623
Abstract
New Hubble Space Telescope and Spitzer Space Telescope observations of the luminous infrared galaxy merger NGC 2623 are presented. This galaxy was observed as part of the Great Observatories All-sky LIRG Survey (GOALS). The prominent 3.2 kpc southern extension to the nucleus is resolved by HST observations into 100 star clusters with optical colors primarily consistent with ages of 1-100 Myr. Archival GALEX data show the off-nuclear region to be extremely bright in the far-UV, being equivalent in luminosity to the resolved nuclear region of 0.15 micron, but becoming less energetically significant at increasing wavelengths. The Spitzer IRS observations confirm the inference from the X-ray and radio data that an active galactic nucleus (AGN) is present. Thus, the off-nuclear optical clusters are associated with a secondary burst of activity with a derived star formation rate of 0.1-0.2 solar masses per year; the bulk of infrared (and thus bolometric) luminosity is generated via star formation and an AGN embedded behind dust within the inner kilo-parsec of the system. If the infrared luminosity is primarily reprocessed starlight, the off-nuclear starburst accounts for <1% of the present star formation in NGC 2623.
- Publication:
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American Astronomical Society Meeting Abstracts #213
- Pub Date:
- January 2009
- Bibcode:
- 2009AAS...21333406E