Cosmological weak lensing with the HST GEMS survey

Catherine Heymans^*, Michael L. Brown, Marco Barden, John A.R. Caldwell, Knud Jahnke, Chien Y. Peng, Hans Walter Rix, Andy Taylor, Steven V.W. Beckwith, Eric F. Bell, Andrea Borch, Boris Häußler, Shardha Jogee, Daniel H. McIntosh, Klaus Meisenheimer, Sebastian F. Sánchez, Rachel Somerville, Lutz Wisotzki, Christian Wolf