Mitigating Imaging Systematics for DESI 2024 Emission Line Galaxies and Beyond

Understand

Emission Line Galaxies (ELGs) are one of the main tracers that the Dark Energy Spectroscopic Instrument (DESI) uses to probe the universe.

• However, they are afflicted by strong spurious correlations between target density and observing conditions known as imaging systematics.
• We present the imaging systematics mitigation applied to the DESI Data Release 1 (DR1) large-scale structure catalogs used in the DESI 2024 cosmological analyses.
• We also explore extensions of the fiducial treatment.