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Dust Absorption and the Cosmic UV Flux Density

M. Massarotti·A. Iovino·A. Buzzoni
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Abstract

We study the evolution of the galaxy UV luminosity density as a function of redshift in the Hubble Deep Field North (HDF-N). We estimate the amount of energy absorbed by dust and hidden from optical observations by analyzing the HDF-N photometric data with the spectral energy distribution fitting method. According to our results, at redshifts 1 < z < 4.5, the global energy observed in the UV rest-frame at lambda=1500 A corresponds to only 7-11% of the stellar energy output, the rest of it being absorbed by dust and re-emitted in the far-IR. Our estimates of the comoving star formation rate density in the universe from the extinction-corrected UV emission are consistent with the recent results obtained with Submillimeter Common-User Bolometer Array (SCUBA) at faint sub-millimeter flux levels.

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M. Massarotti, A. Iovino, A. Buzzoni. 2001-09-03. Dust Absorption and the Cosmic UV Flux Density. https://doi.org/10.1086/323787

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