2012/08/01 by M. R. Becker, Matthew R. Becker · 1 citation
Mathematics · Physics and Astronomy · #Algorithm #Astronomy and Astrophysical Research #Astrophysics #COSMIC cancer database #Computer science #Cosmology and Gravitation Theories #Estimator #Galaxies: Formation, Evolution, Phenomena #Geometry #Linear subspace #Mathematical analysis #Mathematics #Mode (computer interface) #Physics #Shear (geology) #Statistical physics #Statistics #Subspace topology #astro-ph.CO
paper · pdf · doi:10.1093/mnras/stt1396
15 pages, 5 figures, 3 appendices, MNRAS submitted, comments welcome!
arxiv created 2012/08/01 · openalex publication_date 2013/08/20 · arxiv updated 2015/06/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this work, I study the problem of E/B-mode separation with binned cosmic shear two-point correlation function data. Motivated by previous work on E/B-mode separation with shear two-point correlation functions and the practical considerations of data analysis, I consider E/B-mode estimators which are linear combinations of the binned shear correlation function data points. I argue that for most surveys, these estimators mix E and B modes and provide proof of this mixing for the simplest case. I, then, show how to define estimators which minimize this E/B-mode mixing and give practical recipes for their construction and use. Using these optimal estimators, I demonstrate that the vector space composed of the binned shear correlation function data points can be decomposed into approximately ambiguous-, E- and B-mode subspaces. With simple Fisher information estimates, I show that a non-trivial amount of information on typical cosmological parameters is contained in the ambiguous-mode subspace computed in this formalism. Next, I give two examples which apply these practical estimators and recipes to generic problems in cosmic shear data analysis: data compression and spatially locating B-mode contamination. In particular, by using wavelet-like estimators with the shear correlation functions directly, one can pinpoint B-mode contamination to specific angular scales and extract information on its shape. Finally, I discuss how these estimators can be used as part of blinded or closed-box cosmic shear data analyses in order to assess and find B-mode contamination at high precision while avoiding observer biases.