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arXiv · 1601.02618

Spectral Distortion of the CMB by the Cumulative CO Emission from Galaxies throughout Cosmic History

Natalie Mashian·Abraham Loeb·Amiel Sternberg
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Abstract

We show that the cumulative CO emission from galaxies throughout cosmic history distorts the spectrum of the cosmic microwave background (CMB) at a level that is well above the detection limit of future instruments, such as the Primordial Inflation Explorer (PIXIE). The modeled CO signal has a prominent bump in the frequency interval 100-200 GHz, with a characteristic peak intensity of ~ 2$\times$10$^{-23}$ W m$^{-2}$ Hz$^{-1}$ sr$^{-1}$. Most of the CO foreground originates from modest redshifts, z ~ 2-5, and needs to be efficiently removed for more subtle distortions from the earlier universe to be detected.

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Natalie Mashian, Abraham Loeb, Amiel Sternberg. 2016-01-11. Spectral Distortion of the CMB by the Cumulative CO Emission from Galaxies throughout Cosmic History. https://doi.org/10.1093/mnrasl/slw027

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