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Gravity and Non-gravity Modes in the VIRMOS-DESCART Weak Lensing Survey

Ue-Li Pen·Ludovic van Waerbeke·Yannick Mellier
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Abstract

We analyze the weak lensing data of the VIRMOS imaging survey using projections (called E and B-modes) of the two independents observed correlation functions. The E-mode contains all the lensing signal, while noise and systematics contribute equally to the E and B modes provided that intrinsic alignment is negligible. The mode separation allows a measurement of the signal with a \sqrt{2} smaller error bars, and a separate channel to test for systematic errors. We apply various transformations, including a spherical harmonic space power spectrum C^E_l and C^B_l, which provides a direct measurement of the projected dark matter distribution for 500<l<10^4.

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Ue-Li Pen, Ludovic van Waerbeke, Yannick Mellier. 2001-11-04. Gravity and Non-gravity Modes in the VIRMOS-DESCART Weak Lensing Survey. https://doi.org/10.1086/338576

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