UNIONS: The impact of systematic errors on weak-lensing peak counts

Understand

UNIONS is an ongoing deep photometric multi-band survey of the Northern sky.

• As part of UNIONS, CFIS provides r-band data which we use to study weak-lensing peak counts for cosmological inference.
• We assess systematic effects for weak-lensing peak counts and their impact on cosmological parameters for the UNIONS survey.
• In particular, we present results on local calibration, metacalibration shear bias, baryonic feedback, the source galaxy redshift estimate, intrinsic alignment, and the cluster member dilution.