Evolution of the Rate and Mode of Star Formation in Galaxies
نویسنده
چکیده
We present the star formation rate (SFR) and starburst fraction (SBF) for a sample of field galaxies from the ICBS intermediate-redshift cluster survey. We use [O II] and Spitzer 24 μm fluxes to measure SFRs, and 24 μm fluxes and Hδ absorption to measure of SBFs, for both our sample and a present-epoch field sample from the Sloan Digital Sky Survey (SDSS) and Spitzer Wide-area Infrared Extragalactic (SWIRE) survey. We find a precipitous decline in the SFR since z = 1, in agreement with other studies, as well as a corresponding rapid decline in the fraction of galaxies undergoing long-duration moderate-amplitude starbursts. We suggest that the change in both the rate and mode of star formation could result from the strong decrease since z = 1 of gas available for star formation. Subject headings: galaxies: evolution — galaxies: starburst — galaxies: stellar content
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تاریخ انتشار 2009