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arXiv · 0812.0592

Evolution of Lyman Alpha Galaxies: Stellar Populations at z ~ 0.3

Steven L. Finkelstein·Seth H. Cohen·Sangeeta Malhotra·James E. Rhoads
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Abstract

We present the results of a stellar population analysis of 30 Lyman alpha emitting galaxies (LAEs) at z ~ 0.3, previously discovered with the Galaxy Evolution Explorer (GALEX). With a few exceptions, we can accurately fit model spectral energy distributions to these objects, representing the first time this has been done for a large sample of LAEs at z < 3, a gap of ~ 8 Gyr in the history of the Universe. From the 26/30 LAEs which we can fit, we find an age and stellar mass range of 200 Myr - 10 Gyr and 10^9 - 10^11 Msol, respectively. These objects thus appear to be significantly older and more massive than LAEs at high-redshift. We also find that these LAEs show a mild trend towards higher metallicity than those at high redshift, as well as a tighter range of dust attenuation and interstellar medium geometry. These results suggest that low-redshift LAEs have evolved significantly from those at high redshift.

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Steven L. Finkelstein, Seth H. Cohen, Sangeeta Malhotra, James E. Rhoads. 2009-05-21. Evolution of Lyman Alpha Galaxies: Stellar Populations at z ~ 0.3. https://doi.org/10.1088/0004-637x%2F700%2F1%2F276

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