학술논문

DESI and DECaLS (D&D): galaxy–galaxy lensing measurements with 1 per cent survey and its forecast
Document Type
article
Source
Monthly Notices of the Royal Astronomical Society. 524(4)
Subject
Astronomical Sciences
Physical Sciences
gravitational lensing: weak
(cosmology:) large-scale structure of Universe
cosmology: observations
Astronomical and Space Sciences
Astronomy & Astrophysics
Astronomical sciences
Particle and high energy physics
Space sciences
Language
Abstract
The shear measurement from the Dark Energy Camera Legacy Survey (DECaLS) provides an excellent opportunity for galaxy-galaxy lensing study with the Dark Energy Spectroscopic Instrument (DESI) galaxies, given the large (∼9000 deg2) sky overlap. We explore this potential by combining the DESI 1 per cent survey and DECaLS Data Release 8 (DR8). With ∼106 deg2 sky overlap, we achieve significant detection of galaxy-galaxy lensing for Bright Galaxy Survey (BGS) and luminous red galaxy (LRG) as lenses. Scaled to the full BGS sample, we expect the statistical errors to improve from to a promising level of at. 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