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arXiv · 0707.2443

Correlated Anisotropies in the Cosmic Far-Infrared Background Detected by MIPS/Spitzer: Constraint on the Bias

G. Lagache·N. Bavouzet·N. Fernandez-Conde·N. Ponthieu·T. Rodet·H. Dole·M. -A. Miville-Deschenes·J. -L. Puget
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Abstract

We report the detection of correlated anisotropies in the Cosmic Far-Infrared Background at 160 microns. We measure the power spectrum in the Spitzer/SWIRE Lockman Hole field. It reveals unambiguously a strong excess above cirrus and Poisson contributions, at spatial scales between 5 and 30 arcminutes, interpreted as the signature of infrared galaxy clustering. Using our model of infrared galaxy evolution we derive a linear bias b=1.74 \pm 0.16. It is a factor 2 higher than the bias measured for the local IRAS galaxies. Our model indicates that galaxies dominating the 160 microns correlated anisotropies are at z~1. This implies that infrared galaxies at high redshifts are biased tracers of mass, unlike in the local Universe.

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G. Lagache, N. Bavouzet, N. Fernandez-Conde, N. Ponthieu, T. Rodet, H. Dole, M. -A. Miville-Deschenes, J. -L. Puget. 2007-07-17. Correlated Anisotropies in the Cosmic Far-Infrared Background Detected by MIPS/Spitzer: Constraint on the Bias. https://doi.org/10.1086/521301

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