Lensing in the Blue IV: The First Weak Gravitational Lensing Maps from the Stratosphere

SuperBIT, the Super-Pressure Balloon-borne Imaging Telescope, completed its science flight in April 2023 and obtained imaging data for 30 galaxy clusters. This study uses six clusters selected from that target set to present the first weak-lensing convergence maps from the SuperBIT observations.

To build the lensing measurement, the team constructed background-galaxy catalogs from SuperBIT's three-band photometry, applying a color-color-based method to separate foreground and background galaxies. They then used the calibrated galaxy shapes presented in Lensing in the Blue III to reconstruct the weak-lensing convergence field with Kaiser-Squires inversion.

The resulting convergence signal-to-noise maps for the six clusters were compared with independent tracers, including X-ray emission and red-sequence cluster-member number-density maps. According to the authors, these results demonstrate the first successful weak-lensing mass mapping with imaging from a sub-orbital astronomical observatory.