Compressing combined probes: redshift weights for joint lensing and clustering analyses. Issue 2 (21st August 2020)

• Record Type: Journal Article
• Authors: Ruggeri, Rossana; Blake, Chris
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 498:Issue 2(2020)
• Page Start: 2948
• Page End: 2956
• Publication Date: 2020-08-21
• Subjects: gravitational lensing: weak -- methods: statistical -- large-scale structure of Universe; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/staa2537
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: Combining different observational probes, such as galaxy clustering and weak lensing, is a promising technique for unveiling the physics of the Universe with upcoming dark energy experiments. Whilst this strategy significantly improves parameter constraints, decreasing the degeneracies of individual analyses and controlling the systematics, processing data from tens of millions of galaxies is not a trivial task. In this work, we derive and test a new compressed statistic for joint clustering and lensing data analysis, maximizing the scientific return and decreasing the computational cost. Our approach compresses the data by up-weighting the components most sensitive to the parameters of interest, with no loss of information, taking into account information from the cross-correlation between the two probes. We derive optimal redshift weights which may be applied to individual galaxies when testing a given statistic and cosmological model.