Large-scale traces of Solar system cold dust on cosmic microwave background anisotropies

Abstract

We explore the microwave anisotropies on large angular scales produced by the emission from cold and large dust grains, expected to exist in the outer parts of the Solar system, using a simple toy model for this diffuse emission. Its amplitude is constrained in the far-IR by the COBE data and is compatible with simulations found in the literature. We analyse the templates derived after subtracting our model from the WMAP ILC 7-yr maps and investigate on the cosmological implications of such a possible foreground. The anomalies related to the low quadrupole of the angular power spectrum, the two-point correlation function, the parity and the excess of signal found in the ecliptic plane are significantly alleviated. An impact of this foreground on some cosmological parameters characterizing the spectrum of primordial density perturbations, relevant for on-going and future cosmic microwave background anisotropy experiments, is found. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.