Constraining quark angular momentum with the Sivers function.

Alessandro Bacchetta & Marco Radici
Currently, the best way to determine quark total angular momentum requires the knowledge of the generalized parton distribution $E$ in the forward limit. We present the results of a recent work where we assumed a connection between this function and the Sivers transverse-momentum distribution. Using this assumption, we fitted at the same time nucleon anomalous magnetic moments and semi-inclusive single-spin asymmetries. This allowed us to give an estimate of the total angular momentum carried by...