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arXiv · 1004.3542

Shear Power Spectrum Reconstruction using Pseudo-Spectrum Method

Chiaki Hikage·Masahiro Takada·Takashi Hamana·David Spergel
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Abstract

We develop a pseudo power spectrum technique for measuring the lensing power spectrum from weak lensing surveys in both the full sky and flat sky limits. The power spectrum approaches have a number of advantages over the traditional correlation function approach. We test the pseudo spectrum method by using numerical simulations with square-shape boundary that include masked regions with complex configuration due to bright stars and saturated spikes. Even when 25% of total area of the survey is masked, the method recovers the E-mode power spectrum at a sub-percent precision over a wide range of multipoles 100<l<10000. The systematic error is smaller than the statistical errors expected for a 2000 square degree survey. The residual B-mode spectrum is well suppressed in the amplitudes at less than a percent level relative to the E-mode. We also find that the correlated errors of binned power spectra caused by the survey geometry effects are not significant. Our method is applicable to the current and upcoming wide-field lensing surveys.

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Chiaki Hikage, Masahiro Takada, Takashi Hamana, David Spergel. 2010-04-20. Shear Power Spectrum Reconstruction using Pseudo-Spectrum Method. https://doi.org/10.1111/j.1365-2966.2010.17886.x

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