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Reconstructing the Primordial Spectrum with CMB Temperature and Polarization

Noriyuki Kogo·Misao Sasaki·Jun'ichi Yokoyama
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Abstract

We develop a new method to reconstruct the power spectrum of primordial curvature perturbations, $P(k)$, by using both the temperature and polarization spectra of the cosmic microwave background (CMB). We test this method using several mock primordial spectra having non-trivial features including the one with an oscillatory component, and find that the spectrum can be reconstructed with a few percent accuracy by an iterative procedure in an ideal situation in which there is no observational error in the CMB data. In particular, although the previous ``cosmic inversion'' method, which used only the temperature fluctuations, suffered from large numerical errors around some specific values of $k$ that correspond to nodes in a transfer function, these errors are found to disappear almost completely in the new method.

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Noriyuki Kogo, Misao Sasaki, Jun'ichi Yokoyama. 2004-09-02. Reconstructing the Primordial Spectrum with CMB Temperature and Polarization. https://doi.org/10.1103/physrevd.70.103001

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