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arXiv · 1611.00042

AKARI near-infrared background fluctuations arise from normal galaxy populations

Kári Helgason·Eiichiro Komatsu
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Abstract

We show that measurements of the fluctuations in the near-infrared background (NIRB) from the AKARI satellite can be explained by faint galaxy populations at low redshifts. We demonstrate this using reconstructed images from deep galaxy catalogs (HUGS/S-CANDELS) and two independent galaxy population models. In all cases, we find that the NIRB fluctuations measured by AKARI are consistent with faint galaxies and there is no need for a contribution from unknown populations. We find no evidence for a steep Rayleigh-Jeans spectrum for the underlying sources as previously reported. The apparent Rayleigh-Jeans spectrum at large angular scales is likely a consequence of galaxies being removed systematically to deeper levels in the longer wavelength channels.

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Kári Helgason, Eiichiro Komatsu. 2016-10-31. AKARI near-infrared background fluctuations arise from normal galaxy populations. https://doi.org/10.1093/mnrasl%2Fslw251

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