The DECADE cosmic shear project IV: cosmological constraints from 107 million galaxies across 5,400 deg$^2$ of the sky

Understand

We present cosmological constraints from the Dark Energy Camera All Data Everywhere (DECADE) cosmic shear analysis.

• This work uses shape measurements for 107 million galaxies measured through Dark Energy Camera (DECam) imaging of $5,\!412$ deg$^2$ of sky that is outside the Dark Energy Survey (DES) footprint.
• We derive constraints on the cosmological parameters $S_8 = 0.791^{+0.027}_{-0.032}$ and $\Omega_{\rm m} =0.269^{+0.034}_{-0.050}$ for the $\Lambda$CDM model, which are consistent with those from other weak lensing surveys and from the cosmic microwave background.
• We combine our results with cosmic shear results from DES Y3 at the likelihood level, since the two datasets span independent areas on the sky.