A framework for measuring weak-lensing magnification using the Fundamental Plane

Journal Article · 04 June 2020 · Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/staa1505 · OSTI ID:1636227

Freudenburg, Jenna K. C.  ^[1]; Huff, Eric M. ^[2]; Hirata, Christopher M. ^[1]

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1. The Ohio State Univ., Columbus, OH (United States). Center for Cosmology and AstroParticle Physics (CCAPP)
2. California Institute of Technology (CalTech), Pasadena, CA (United States). Jet Propulsion Lab. (JPL)

Galaxy–galaxy lensing is an essential tool for probing dark matter haloes and constraining cosmological parameters. While galaxy–galaxy lensing measurements usually rely on shear, weak-lensing magnification contains additional constraining information. Using the Fundamental Plane (FP) of elliptical galaxies to anchor the size distribution of a background population is one method that has been proposed for performing a magnification measurement. We present a formalism for using the FP residuals of elliptical galaxies to jointly estimate the foreground mass and background redshift errors for a stacked lens scenario. The FP residuals include information about weak-lensing magnification κ, and therefore foreground mass, since to first order, non-zero κ affects galaxy size but not other FP properties. We also present a modular, extensible code that implements the formalism using emulated galaxy catalogues of a photometric galaxy survey. We find that combining FP information with observed number counts of the source galaxies constrains mass and photo-z error parameters significantly better than an estimator that includes number counts only. In particular, the constraint on the mass is 17.0 per cent if FP residuals are included, as opposed to 27.7 per cent when only number counts are included. The effective size noise for a foreground lens of mass $$M_\mathrm{H}=10^{14}\, \mathrm{M}_\odot$$, with a conservative selection function in size and surface brightness applied to the source population, is σκ, eff = 0.250. We discuss the improvements to our FP model necessary to make this formalism a practical companion to shear analyses in weak-lensing surveys.

• Research Organization: The Ohio State Univ., Columbus, OH (United States)
• Sponsoring Organization: USDOE Office of Science (SC); USDOE
• Grant/Contract Number: SC0019083
• OSTI ID: 1636227
• Alternate ID(s): OSTI ID: 1803551
• Journal Information: Monthly Notices of the Royal Astronomical Society, Vol. 496, Issue 3; ISSN 0035-8711
• Publisher: Royal Astronomical SocietyCopyright Statement
• Country of Publication: United States
• Language: English