Star Formation in the Nearby Universe: The Ultraviolet and Infrared Points of View
Abstract
This work presents the main ultraviolet (UV) and far-infrared (FIR) properties of two samples of nearby galaxies selected from the GALEX (λ = 2315 Å, hereafter NUV) and IRAS (λ = 60 μm) surveys, respectively. They are built in order to obtain detection at both wavelengths for most of the galaxies. Star formation rate (SFR) estimators based on the UV and FIR emissions are compared. Systematic differences are found between the SFR estimators for individual galaxies based on the NUV fluxes corrected for dust attenuation and on the total IR luminosity. A combined estimator based on NUV and IR luminosities seems to be the best proxy over the whole range of values of SFR. Although both samples present similar average values of the birthrate parameter b, their star-formation-related properties are substantially different: NUV-selected galaxies tend to show larger values of b for lower masses, SFRs, and dust attenuation, supporting previous scenarios of star formation history (SFH). Conversely, about 20% of the FIR-selected galaxies show high values of b, SFR, and NUV attenuation. These galaxies, most of them being LIRGs and ULIRGs, break down the downsizing picture of SFH; however, their relative contribution per unit volume is small in the local universe. Finally, the cosmic SFR density of the local universe is estimated in a consistent way from the NUV and IR luminosities.
Additional Information
© 2006 American Astronomical Society. Received 2005 April 15; accepted 2006 January 10. GALEX is a NASA Small Explorer, launched in 2003 April. We gratefully acknowledge NASA's support for the construction, operation, and science analysis for the GALEX mission, developed in cooperation with the Centre National d'Etudes Spatiales of France and the Korean Ministry of Science and Technology. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. The Lyon Extragalactic Database (LEDA) is available at http://leda.univ-lyon1.fr. T. T. T. has been financially supported by the Japan Society for the Promotion of Science.Attached Files
Published - IGLapjss06.pdf
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Additional details
- Eprint ID
- 23680
- Resolver ID
- CaltechAUTHORS:20110516-141002586
- Japan Society for the Promotion of Science (JSPS)
- Created
-
2011-05-17Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Space Radiation Laboratory, Space Astrophysics Laboratory