2005/12/07 by X. Z. Zheng, Xianzhong Zheng, E. F. Bell +10 · 3 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/500253
published as Astrophys.J.640:784-800,2006 · 12 figures, 2 tables, 14 pages (+5 page Appendix), accepted for publication in ApJ
arxiv created 2005/12/07 · openalex publication_date 2006/03/27 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
We stack Spitzer 24 μm images for ~7000 galaxies with 0.1 ≤ z < 1 in the Chandra Deep Field South to probe the thermal dust emission in low-luminosity galaxies over this redshift range. Through stacking, we can detect mean 24 μm fluxes that are more than an order of magnitude below the individual detection limit. We find that the correlations for low- and moderate-luminosity galaxies between the average L IR / L UV and rest-frame B -band luminosity, and between the star formation rate (SFR) and L IR / L UV , are similar to those in the local universe. This verifies that oft-used assumption in deep UV/optical surveys that the dust obscuration-SFR relation for galaxies with SFR ≤ 20 M ☉ yr -1 varies little with epoch. We have used this relation to derive the cosmic IR luminosity density from z = 1 to z = 0.1. The results also demonstrate directly that little of the bolometric luminosity of the galaxy population arises from the faint end of the luminosity function, indicating a relatively flat faint-end slope of the IR luminosity function with a power-law index of 1.2 ± 0.3.