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arXiv · 0808.0673

Pseudoscalar perturbations and polarization of the cosmic microwave background

Maxim Pospelov·Adam Ritz·Constantinos Skordis
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Abstract

We show that models of new particle physics containing massless pseudoscalar fields super-weakly coupled to photons can be very efficiently probed with CMB polarization anisotropies. The stochastic pseudoscalar fluctuations generated during inflation provide a mechanism for converting E-mode polarization to B-mode during photon propagation from the surface of last scattering. The efficiency of this conversion process is controlled by the dimensionless ratio H/(2πf_a), where H is the Hubble scale during inflation, and f_a^{-1} is the strength of the pseudoscalar coupling to photons. The current observational limits on the B-mode constrain this ratio to be less than 0.07, which in many models of inflation translates to a sensitivity to values of f_a in excess of 10^{14} GeV, surpassing the sensitivity of other tests.

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Maxim Pospelov, Adam Ritz, Constantinos Skordis. 2008-08-05. Pseudoscalar perturbations and polarization of the cosmic microwave background. https://doi.org/10.1103/physrevlett.103.051302

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