|Speaker||Talk Date||Talk Series|
|Shude Mao (Manchester & NAOC)||8 August 2012||Institute of Astronomy Seminars|
Hierarchical structure formation theory predicts tri-axial halo shapes and density profiles. Gravitational lensing flexion is related to the derivative of the weak lensing shear and convergence. We show that, as a higher order derivative of the lensing potential, the flexion can be used to test these predictions.