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arXiv · 1012.0444

Information Content in the Angular Power Spectrum of Weak Lensing: Wavelet Method

Hao-Ran Yu·Joachim Harnois-Déraps·Tong-Jie Zhang·Ue-Li Pen
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Abstract

We quantify the performance of a non-linear Wiener filter, constructed in wavelet space, at recovering some of the Fisher information that was lost in the weak lensing convergence field. The proposed method consists in a separation of the original field into the sum of a Gaussian and a non-Gaussian contribution. After filtering an ensemble of such fields, which are obtained from $N$-body simulations, we find that we can recapture about four times more Fisher information, an effect that can potentially improve by a significant amount the constraining power of weak lensing surveys on cosmological parameters, including the dark energy equation of state $ω$. We compare this performance with that of the logarithmic mapping and find that the wavelet method can recover up to three times more information.

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Hao-Ran Yu, Joachim Harnois-Déraps, Tong-Jie Zhang, Ue-Li Pen. 2011-12-15. Information Content in the Angular Power Spectrum of Weak Lensing: Wavelet Method. https://doi.org/10.1111/j.1365-2966.2011.20360.x

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