Results of the GREAT08 Challenge: An image analysis competition for cosmological lensing

Understand

We present the results of the GREAT08 Challenge, a blind analysis challenge to infer weak gravitational lensing shear distortions from images.

• The primary goal was to stimulate new ideas by presenting the problem to researchers outside the shear measurement community.
• Six GREAT08 Team methods were presented at the launch of the Challenge and five additional groups submitted results during the 6 month competition.
• Participants analyzed 30 million simulated galaxies with a range in signal to noise ratio, point-spread function ellipticity, galaxy size, and galaxy type.