Optimal Surveys for Weak Lensing Tomography

By Adam Amara, Alexandre Refregier. 2006

136 citations recorded by the source corpus.

Weak-lensing surveys provide a powerful probe of dark energy through the measurement of the mass distribution of the local Universe. A number of ground-based and space-based surveys are being planned for this purpose. Here, we study the optimal strategy for these future surveys using the joint constraints on the equation-of-state parameter w n and its evolution w a as a figure of merit by considering power spectrum tomography. For this purpose, we first consider an 'ideal' survey which is both wide and deep and exempt from systematics. We find that such a survey has great potential for dark energy studies, reaching 1σ precisions of 1 and 10 per cent on the two parameters, respectively. We then study the relative impact of various limitations by degrading this ideal survey. In particular, we consider the effect of sky coverage, survey depth, shape measurement systematics, photometric redshift systematics and uncertainties in the non-linear power spectrum predictions. We find that, for a given observing time, it is always advantageous to choose a wide rather than a deep survey geometry. We also find that the dark energy constraints from power spectrum tomography are robust to photometric redshift errors and catastrophic failures, if a spectroscopic calibration sample of 10 4 -10 5 galaxies are available. The impact of these systematics is small compared to the limitations that come from potential uncertainties in the power spectrum, due to shear measurement and theoretical errors. To help the planning of future surveys, we summarize our results with comprehensive scaling relations which avoid the need for full Fisher matrix calculations.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/401e7e46e61c9563b26bfc1e23de9c05fdabea33

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Citations in the corpus

Origins of weak lensing systematics, and requirements on future instrumentation (or knowledge of instrumentation) (2012, methodology): “We now propagate hypothetical shear measurement errors A(`, zA, zB) and M(`, zA, zB) from Section 3 into biases on derived cosmological parameters, via the Fisher matrix bias formalism (Taylor & Watts 2001; see also Amara & Réfrégier 2007, Kitching et al. 2009b).”
Constraining primordial non-Gaussianity with future galaxy surveys (2011, unknown): “(20) yields (Hu & Jain 2004; Amara & Refregier 2007) F αβ = fsky lmax∑ l=lmin (2l + 1) 2 Tr [ D lα ( C̃ l )−1 D lβ ( C̃ l )−1] , (30) where fsky is the sky coverage of the survey.”
Weak Gravitational Lensing (2012, background): “It is the so-called cosmic shear tomography [34, 2].”
KiDS+GAMA : cosmology constraints from a joint analysis of cosmic shear, galaxy-galaxy lensing, and angular clustering (2017, background): “This procedure basically marginalizes over the first moment of the redshift distribution, which is, to first order, what the weak lensing signal is sensitive to Amara & Réfrégier (2007).”