Cosmic shear power spectra in practice
نویسندگان
چکیده
Cosmic shear is one of the most powerful probes Dark Energy, targeted by several current and future galaxy surveys. Lensing shear, however, only sampled at positions galaxies with measured shapes in catalog, making its associated sky window function complicated amongst all projected cosmological inhomogeneities, as well giving rise to inhomogeneous noise. Partly for this reason, cosmic analyses have been mostly carried out real-space, use correlation functions, opposed Fourier-space power spectra. Since spectra can yield complementary information has numerical advantages over real-space pipelines, it important develop a complete formalism describing standard unbiased spectrum estimators their uncertainties. Building on previous work, paper contains study main complications estimating interpreting spectra, presents fast accurate methods estimate two key quantities needed practical usage: noise bias Gaussian covariance matrix, fully accounting survey geometry, some these results also applicable other probes. We demonstrate performance applying them latest public data releases Hyper Suprime-Cam Energy Survey collaborations, quantifying presence systematics our measurements validity matrix estimate. make resulting matrices, null tests necessary full analysis publicly available.
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2021
ISSN: ['1475-7516', '1475-7508']
DOI: https://doi.org/10.1088/1475-7516/2021/03/067