Systematic bias in cosmic shear: extending the Fisher matrix

By Adam Amara, Alexandre Refregier. 2007

141 citations recorded by the source corpus.

We describe a method for computing the biases that systematic signals introduce in parameter estimation using a simple extension of the Fisher matrix formalism. This allows us to calculate the offset of the best fit parameters relative to the fiducial model, in addition to the usual statistical error ellipse. As an application, we study the impact that residual systematics in tomographic weak lensing measurements. In particular we explore three different types of shape measurement systematics: (i) additive systematic with no redshift evolution; (ii) additive systematic with redshift evolution; and (iii) multiplicative systematic. In each case, we consider a wide range of scale dependence and redshift evolution of the systematics signal. For a future DUNE-like full sky survey, we find that, for cases with mild redshift evolution, the variance of the additive systematic signal should be kept below 10 7 to ensure biases on cosmological parameters that are sub-dominant to the statistical errors. For the multiplicative systematics, which depends on the lensing signal, we find the multiplicative calibration m0 needs to be controlled to an accuracy better than 10 3 . We find that the impact of systematics can be underestimated if their assumes redshift dependence is too simplistic. We provide simple scaling relations to extend these requirements to any survey geometry and discuss the impact of our results for current and future weak lensing surveys.

Subfields: Astronomy and Astrophysics, Atomic and Molecular Physics, and Optics

View Paper: https://www.semanticscholar.org/paper/8b688847de3cad65acdc9d5b344c7ed4111526b6

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Citations in the corpus

Cosmology with Phase 1 of the Square Kilometre Array Red Book 2018: Technical specifications and performance forecasts (2018, methodology): “For the Medium-Deep Band 2 Survey, the formulae of Amara & Réfrégier (2008) allow us to calculate requirements on the multiplicative shear bias of σm 6.4× 10−3 and additive shear bias of σc 8.0× 10−4.”
Constraints on intrinsic alignment contamination of weak lensing surveys using the MegaZ-LRG sample (2010, unknown): “…one can calculate the bias on a cosmological parameter via (e.g. Kim et al. 2004; Huterer & Takada 2005; Huterer et al. 2006; Taylor et al. 2007; Amara & Réfrégier 2008; Kitching et al. 2009; Joachimi & Schneider 2009) b(pµ) = ∑ ν ( F−1 ) µν ∑ ℓ,i≤ j,k≤l [ C(i j)II (ℓ) +C (i j) GI (ℓ) ] (26) ×…”
Results of the GREAT08 Challenge?: an image analysis competition for cosmological lensing: Results o (2009, background): “Amara & Réfrégier (2008) show that a deep full-sky (e.g. Euclidlike) survey requires that the additive error c 0.0003 and the multiplicative error m < 0.001.”
The first-year shear catalog of the Subaru Hyper Suprime-Cam Subaru Strategic Program Survey (2017, result): “The overall process described here is broadly consistent with that used for several ongoing and future surveys (Amara & Réfrégier 2008; Massey et al. 2013; Jarvis et al. 2016; Hildebrandt et al. 2017), differing only in small details of the implementation.”
The Intrinsic Alignment of Galaxies and its Impact on Weak Gravitational Lensing in an Era of Precision Cosmology (2014, methodology): “…Ade et al., 2013b,c; Das et al., 2014) have been suggested as a method for calibrating multiplicative biases in galaxy lensing (Vallinotto, 2012; Das et al., 2013), which are difficult to constrain and degenerate with the growth function (e.g., Huterer et al. (2006); Amara and Réfrégier (2008)).”
Galaxy Alignments: Observations and Impact on Cosmology (2015, background): “…of the bias on cosmological parameters, ∆pα, when an incorrect cosmological 8http://www.euclid-ec.org/ model is assumed (Huterer et al. 2006; see also Amara & Réfrégier 2008 and Appendix A of Joachimi et al. 2011): ∆pα = ∑ β F−1αβ ∑ ` ∑ i≤ j;m≤n ∆C(i j) (`) ( Cov [ C(i j) (`),C(mn) (`) ])−1…”
CFHTLenS: the Canada–France–Hawaii Telescope Lensing Survey – imaging data and catalogue products (2012, methodology): “In order for a tomographic cosmic shear analysis of CFHTLenS not to be dominated by systematic errors we can estimate a ballpark tolerance for the level of PSF related systematics in the data (Amara & Réfrégier 2008).”
Origins of weak lensing systematics, and requirements on future instrumentation (or knowledge of instrumentation) (2012, methodology): “20 of Amara & Réfrégier 2008).”
Cosmology from the Chinese Space Station Optical Survey (CSS-OS) (2019, background): “…the measured shear power spectrum at a given multipole ` for the ith and jth tomographic bins can be estimated by (e.g. Huterer et al. 2006; Amara & Refregier 2008) C̃ijγ (`) = (1 +mi)(1 +mj)C ij γ (`) + δij σ2γ n̄i +N ijadd(`), (5) where Cijγ (`) is named as signal power spectrum, which…”
The DES Science Verification weak lensing shear catalogues (2015, result): “We note that these results are broadly consistent with those of Amara & Réfrégier (2008), who derived requirements for a tomographic weak lensing survey, performing joint constraints on the set of cosmological parameters for a wCDM model.”