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This content will become publicly available on October 22, 2026

Title: The DECADE cosmic shear project I: A new weak lensing shape catalog of 107 million galaxies
We present the Dark Energy Camera All Data Everywhere (DECADE) weak lensing dataset: a catalog of 107 million galaxies observed by the Dark Energy Camera (DECam) in the northern Galactic cap. This catalog was assembled from public DECam data including survey and standard observing programs. These data were consistently processed with the Dark Energy Survey Data Management pipeline as part of the DECADE campaign and serve as the basis of the DECam Local Volume Exploration survey (DELVE) Early Data Release 3 (EDR3). We apply the Metacalibration measurement algorithm to generate and calibrate galaxy shapes. After cuts, the resulting cosmology-ready galaxy shape catalog covers a region of 5,412 deg2 with an effective number density of 4.59 arcmin−2. The coadd images used to derive this data have a median limiting magnitude of r=23.6, i=23.2, and z=22.6, estimated at S/N=10 in a 2 arcsecond aperture. We present a suite of detailed studies to characterize the catalog, measure any residual systematic biases, and verify that the catalog is suitable for cosmology analyses. In parallel, we build an image simulation pipeline to characterize the remaining multiplicative shear bias in this catalog, which we measure to be m=(−2.454±0.124)×10−2 for the full sample. Despite the significantly inhomogeneous nature of the data set, due to it being an amalgamation of various observing programs, we find the resulting catalog has sufficient quality to yield competitive cosmological constraints.  more » « less
Award ID(s):
2108168 2307126 2407526
PAR ID:
10651931
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
Open Journal of Astrophysics
Date Published:
Journal Name:
The Open Journal of Astrophysics
Volume:
8
ISSN:
2565-6120
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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