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arXiv · 1411.1411

On the Origin of Near-Infrared Extragalactic Background Light Anisotropy

Michael Zemcov·Joseph Smidt·Toshiaki Arai·James Bock·Asantha Cooray·Yan Gong·Min Gyu Kim·Phillip Korngut·Anson Lam·Dae Hee Lee·Toshio Matsumoto·Shuji Matsuura·Uk Won Nam·Gael Roudier·Kohji Tsumura·Takehiko Wada
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Abstract

Extragalactic background light (EBL) anisotropy traces variations in the total production of photons over cosmic history, and may contain faint, extended components missed in galaxy point source surveys. Infrared EBL fluctuations have been attributed to primordial galaxies and black holes at the epoch of reionization (EOR), or alternately, intra-halo light (IHL) from stars tidally stripped from their parent galaxies at low redshift. We report new EBL anisotropy measurements from a specialized sounding rocket experiment at 1.1 and 1.6 micrometers. The observed fluctuations exceed the amplitude from known galaxy populations, are inconsistent with EOR galaxies and black holes, and are largely explained by IHL emission. The measured fluctuations are associated with an EBL intensity that is comparable to the background from known galaxies measured through number counts, and therefore a substantial contribution to the energy contained in photons in the cosmos.

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Michael Zemcov, Joseph Smidt, Toshiaki Arai, James Bock, Asantha Cooray, Yan Gong, Min Gyu Kim, Phillip Korngut, Anson Lam, Dae Hee Lee, Toshio Matsumoto, Shuji Matsuura, Uk Won Nam, Gael Roudier, Kohji Tsumura, Takehiko Wada. 2014-11-05. On the Origin of Near-Infrared Extragalactic Background Light Anisotropy. https://doi.org/10.1126/science.1258168

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