Delensing Galaxy Surveys
arXiv:1405.1432 · doi:10.1093/mnras/stu1104
Abstract
Weak gravitational lensing can cause displacements, magnification, rotation and shearing of the images of distant galaxies. Most studies focus on the shear and magnification effects since they are more easily observed. In this paper we focus on the effect of lensing displacements on wide field images. Galaxies at redshifts 0.5--1 are typically displaced by 1 arcminute, and the displacements are coherent over degree-size patches. However the displacement effect is redshift-dependent, so there is a visible relative shift between galaxies at different redshifts, even if they are close on the sky. We show that the reconstruction of the original galaxy position is now feasible with lensing surveys that cover many hundreds of square degrees. We test with simulations two approaches to "delensing": one uses shear measurements and the other uses the foreground galaxy distribution as a proxy for the mass. We also estimate the effect of foreground deflections on galaxy-galaxy lensing measurements and find it is relevant only for LSST and Euclid-era surveys.
9 pages, 8 figures, submitted to MNRAS
References in corpus (6)
- CFHTLenS: The Canada-France-Hawaii Telescope Lensing Survey
- Cosmic shear results from the deep lens survey - I: Joint constraints on omega_m and sigma_8 with a two-dimensional analysis
- Constraining the substructure of dark matter haloes with galaxy-galaxy lensing
- Weak Lensing of Baryon Acoustic Oscillations
- The COSMOS Density Field: A Reconstruction Using Both Weak Lensing and Galaxy Distributions
- Universal Weak Lensing Distortion of Cosmological Correlation Functions
Cited by in corpus (5)
- Dark Energy Survey Year 1 Results: Curved-Sky Weak Lensing Mass Map
- Dark Energy Survey Year 3 Results: High-precision measurement and modeling of galaxy-galaxy lensing
- ADDGALS: Simulated Sky Catalogs for Wide Field Galaxy Surveys
- The importance of magnification effects in galaxy-galaxy lensing
- A Hamiltonian, post-Born, three-dimensional, on-the-fly ray tracing algorithm for gravitational lensing