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تسجيل مستخدم جديدWeak Lensing Science, Surveys, and Systematics
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Weak gravitational lensing is one of the key probes of the cosmological model, dark energy, and dark matter, providing insight into both the cosmic expansion history and large scale structure growth history. Taking into account a broad spectrum of physics affecting growth - dynamical dark energy, extended gravity, neutrino masses, and spatial curvature - we analyze the cosmological constraints. Similarly we consider the effects of a range of systematic uncertainties, in shear measurement, photometric redshifts, and the nonlinear power spectrum, on cosmological parameter extraction. We also investigate, and provide fitting formulas for, the influence of survey parameters such as redshift depth, galaxy number densities, and sky area. Finally, we examine the robustness of results for different fiducial cosmologies.
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We present a pedagogical review of the weak gravitational lensing measurement process and its connection to major scientific questions such as dark matter and dark energy. Then we describe common ways of parametrizing systematic errors and understand
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