Discriminating weak lensing from intrinsic spin correlations using the curl-gradient decomposition

The distortion field defined by the ellipticities of galaxy shapes as projected on the sky can be uniquely decomposed into a gradient and a curl component. If the observed ellipticities are induced by weak gravitational lensing, then the distortion field is curl-free. Here we show that, in contrast, the distortion field resulting from int...更多