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arXiv · 1509.02935

Ultraviolet Luminosity Density of the Universe During the Epoch of Reionization

Ketron Mitchell-Wynne·Asantha Cooray·Yan Gong·Matthew Ashby·Timothy Dolch·Henry Ferguson·Steven Finkelstein·Norman Grogin·Dale Kocevski·Anton Koekemoer·Joel Primack·Joseph Smidt
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Abstract

The spatial fluctuations of the extragalactic background light trace the total emission from all stars and galaxies in the Universe. A multi-wavelength study can be used to measure the integrated emission from first galaxies during reionization when the Universe was about 500 million years old. Here we report arcminute-scale spatial fluctuations in one of the deepest sky surveys with the Hubble Space Telescope in five wavebands between 0.6 and 1.6 $μ$m. We model-fit the angular power spectra of intensity fluctuation measurements to find the ultraviolet luminosity density of galaxies at $z$ > 8 to be $\log ρ_{\rm UV} = 27.4^{+0.2}_{-1.2}$ erg s$^{-1}$ Hz$^{-1}$ Mpc$^{-3}$ $(1σ)$. This level of integrated light emission allows for a significant surface density of fainter primeval galaxies that are below the point source detection level in current surveys.

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Ketron Mitchell-Wynne, Asantha Cooray, Yan Gong, Matthew Ashby, Timothy Dolch, Henry Ferguson, Steven Finkelstein, Norman Grogin, Dale Kocevski, Anton Koekemoer, Joel Primack, Joseph Smidt. 2015-09-09. Ultraviolet Luminosity Density of the Universe During the Epoch of Reionization. https://doi.org/10.1038/ncomms8945

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