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The Case For Substantial Dust Extinction At z ~ 3

Gerhardt R. Meurer
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Abstract

Estimates of the total metal production rate (\dotρ_Z) and star formation rate at z > 2 are based on Lyman break systems observed in the rest-frame ultraviolet (UV). These observations are very sensitive to dust obscuration. Here I elucidate and refine the Meurer et al. (1997) method for calculating UV obscuration, presenting new relationships which accurately model the dust reprocessing of radiation in local starbursts. The median lambda = 1600 Angstroms obscuration factor is ~10 at z ~ 3 which is shown to be consistent with other constraints on the high-z \dotρ_Z. Two tests are proposed to further constrain \dotρ_Z at these redshifts.

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Gerhardt R. Meurer. 1997-08-18. The Case For Substantial Dust Extinction At z ~ 3. https://arxiv.org/abs/astro-ph/9708163

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