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arXiv · 0811.0230

The full contribution of a stochastic background of magnetic fields to CMB anisotropies

Daniela Paoletti·Fabio Finelli·Francesco Paci
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Abstract

We study the contribution of a stochastic background (SB) of primordial magnetic fields (PMF) on the anisotropies in temperature and polarization of the cosmic microwave background radiation (CMB). A SB of PMF modelled as a fully inhomogeneous component induces non-gaussian scalar, vector and tensor metric linear perturbations. We give the exact expressions for the Fourier spectra of the relevant energy-momentum components of such SB, given a power-law dependence parametrized by a spectral index $n_B$ for the magnetic field power spectrum cut at a damping scale $k_D$. For all the values of $n_B$ considered here, the contribution to the CMB temperature pattern by such a SB is dominated by the scalar contribution and then by the vector one at higher multipoles. We also give an analytic estimate of the scalar contribution to the CMB temperature pattern.

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Daniela Paoletti, Fabio Finelli, Francesco Paci. 2009-05-22. The full contribution of a stochastic background of magnetic fields to CMB anisotropies. https://doi.org/10.1111/j.1365-2966.2009.14727.x

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