Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-05-16
Astron.J.130:1022-1036,2005
Astronomy and Astrophysics
Astrophysics
35 pages, 11 figures, 3 tables; to appear in the AJ. PS with better figures available from http://www.astro.washington.edu/agu
Scientific paper
10.1086/432160
We discuss the UV, optical, and IR properties of the SDSS sources detected by GALEX as part of its All-sky Imaging Survey Early Release Observations. Virtually all of the GALEX sources in the overlap region are detected by SDSS. GALEX sources represent ~2.5% of all SDSS sources within these fields and about half are optically unresolved. Most unresolved GALEX/SDSS sources are bright blue turn-off thick disk stars and are typically detected only in the GALEX near-UV band. The remaining unresolved sources include low-redshift quasars, white dwarfs, and white dwarf/M dwarf pairs, and these dominate the optically unresolved sources detected in both GALEX bands. Almost all the resolved SDSS sources detected by GALEX are fainter than the SDSS 'main' spectroscopic limit. These sources have colors consistent with those of blue (spiral) galaxies (u-r<2.2), and most are detected in both GALEX bands. Measurements of their UV colors allow much more accurate and robust estimates of star-formation history than are possible using only SDSS data. Indeed, galaxies with the most recent (<20 Myr) star formation can be robustly selected from the GALEX data by requiring that they be brighter in the far-UV than in the near-UV band. However, older starburst galaxies have UV colors similar to AGN, and thus cannot be selected unambiguously on the basis of GALEX fluxes alone. With the aid of 2MASS data, we construct and discuss median 10 band UV-optical-IR spectral energy distributions for turn-off stars, hot white dwarfs, low-redshift quasars, and spiral and elliptical galaxies. We point out the high degree of correlation between the UV color and the contribution of the UV flux to the UV-optical-IR flux of galaxies detected by GALEX.
Jr.
Agueros Marcel A.
Bochanski John
Brooks Alyson
Claire Mark
No associations
LandOfFree
The UV, Optical, and IR Properties of SDSS Sources Detected by GALEX does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The UV, Optical, and IR Properties of SDSS Sources Detected by GALEX, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The UV, Optical, and IR Properties of SDSS Sources Detected by GALEX will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-600381