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The nature of the Lyman-alpha emission region of FDF-4691

C. Tapken·I. Appenzeller·D. Mehlert·S. Noll·S. Richling
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Abstract

In order to study the origin of the strong Lyman-alpha emission of high-redshift starburst galaxies we observed and modeled the emission of the z = 3.304 galaxy FDF-4691 (rest-frame EW = 103 Angstroem). The observations show that FDF-4691 is a young starburst galaxy with a (for this redshift) typical metallicity. The broad, double-peaked profile of the Lyman-alpha emission line can be explained assuming a highly turbulent emission region in the inner part of the starburst galaxy, and a surrounding extended shell of low-density neutral gas with a normal dust/gas ratio and with Galactic dust properties. The detection of the Lyman-alpha emission line is explained by the intrinsic broad Lyman-alpha emission and a low HI column density of the neutral shell. A low dust/gas ratio in the neutral shell is not needed to explain the strong Lyman-alpha line.

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C. Tapken, I. Appenzeller, D. Mehlert, S. Noll, S. Richling. 2004-01-21. The nature of the Lyman-alpha emission region of FDF-4691. https://doi.org/10.1051/0004-6361%3A20040015

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