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Arxiv: Weak gravitational lensing measurements of Abell 2744 using JWST and shear measurement algorithm pyRRG-JWST Published: 1/29/2024 9:00:03 PM Updated: 1/29/2024 9:00:03 PM

Paper abstract: We update the publicly available weak lensing shear measurement algorithmpyRRG for the James Webb Space Telescope, and apply it to UNCOVER DR1 imagingof galaxy cluster Abell 2744. At short wavelengths (< 2.5\mum), shearmeasurements are consistent between independent observations through differentJWST bandpasses, and calibrated within 1.5% of those from the Hubble SpaceTelescope. At longer wavelengths, shear is underestimated by ~5%, probably dueto coarser pixellisation. We model the spatially varying Point Spread Function(PSF) using WebbPSF, whose moments are within 0.05 of real stars near thecentre of the mosaic, where there are sufficient stars to also generate anempirical model. We measure shear from up to 162 galaxies arcminute^2 toderive a map of (dark plus baryonic) mass with 12 arcsecond (55 kpc) spatialresolution. All code, catalogues and maps are available fromhttps://github.com/davidharvey1986/pyRRG.