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Spectroscopy of z>3 Lyman-limit Galaxies

Hyron Spinrad·Arjun Dey·Daniel Stern·Andrew Bunker
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Abstract

We discuss the spectral character of Lyman-limit-selected, star-forming galaxies at z>3. The rest-frame UV spectra of these faint galaxies may show Ly-alpha in either absorption or emission, probably depending upon their local ISM content and geometry. Other UV interstellar resonance absorption lines show considerable variation in strength, likely related to differences in the galactic metal abundances. We present initial results on B-drop galaxies, generally at z~4. Our low-resolution spectrograms show no measurable flux below the redshifted Lyman limit (912 Angstroms). Thus, it is likely that normal, star-forming galaxies at early cosmic epochs did not significantly contribute to the metagalactic ionizing radiation field.

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Hyron Spinrad, Arjun Dey, Daniel Stern, Andrew Bunker. 1998-02-11. Spectroscopy of z>3 Lyman-limit Galaxies. https://arxiv.org/abs/astro-ph/9802150

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