Authors:
Yao, Ji;Shan, Huanyuan;Zhang, Pengjie;Jullo, Eric;Kneib, Jean-Paul;Yu;Zu, Ying;Brooks, David;de la Macorra, Axel;Doel, Peter;Font-Ribera, Andreu;Gontcho, Satya Gontcho A.;Kisner, Theodore;Landriau, Martin;Meisner, Aaron;Miquel, Ramon;Nie, Jundan;Poppett, Claire;Prada, Francisco;Schubnell, Michael;Magana, Mariana Vargas;Zhou, Zhimin
Journal:
Monthly Notices of the Royal Astronomical Society
Abstract:
The shear measurement from DECaLS (Dark Energy Camera Legacy Survey) provides an excellent opportunity for galaxy-galaxy lensing study with DESI (Dark Energy Spectroscopic Instrument) galaxies, given the large (~9000 deg<SUP>2</SUP>) sky overlap. We explore this potential by combining the DESI 1% survey and DECaLS DR8. With ~106 deg<SUP>2</SUP> sky overlap, we achieve significant detection of galaxy-galaxy lensing for BGS and LRG as lenses. Scaled to the full BGS sample, we expect the statistical errors to improve from $18(12)\%$ to a promising level of $2(1.3)\%$ at $\theta >8^{^{\prime }}(<8^{^{\prime }})$. This brings stronger requirements for future systematics control. To fully realize such potential, we need to control the residual multiplicative shear bias |m| < 0.006 and the bias in the mean redshift |Δz| < 0.008, requiring the introduced bias in the measurement is <0.31σ. We also expect significant detection of galaxy-galaxy lensing with DESI LRG/ELG full samples as lenses, and cosmic magnification of ELG through cross-correlation with low-redshift DECaLS shear. If such systematical error control can be achieved, we find the advantages of DECaLS, comparing with KiDS (Kilo Degree Survey) and HSC (Hyper Suprime-Cam), are at low redshift, large-scale, and in measuring the shear-ratio (to σ<SUB>R</SUB> ~ 0.04) and cosmic magnification.
URL:
https://ui.adsabs.harvard.edu/#abs/2023MNRAS.524.6071Y/abstract
Keywords:
gravitational lensing: weak;(cosmology:) large-scale structure of Universe;surveys