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arXiv · 1102.1524

B polarization of cosmic background radiation from second-order scattering sources

M. Beneke·C. Fidler·K. Klingmuller
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Abstract

B-mode polarization of the cosmic background radiation is induced from purely scalar primordial sources at second order in perturbations of the homogeneous, isotropic universe. We calculate the B-mode angular power spectrum C_l^{BB} sourced by the second-order scattering term in the full second-order Boltzmann equations for the polarized radiation phase-space density, which have recently become available. We find that at l\approx 200 the second-order effect is comparable to the first-order effect for a tensor-to-scalar ratio of r=10^{-6}, and to about 2\cdot 10^{-4} at l\approx 1000. It is always negligible relative to the weak-lensing induced contribution.

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M. Beneke, C. Fidler, K. Klingmuller. 2011-02-08. B polarization of cosmic background radiation from second-order scattering sources. https://doi.org/10.1088/1475-7516/2011/04/008

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