Quark Orbital Angular Momentum in the Wandzura–Wilczek Approximation
نویسندگان
چکیده
We show that quark orbital angular momentum is directly related to offforward correlation functions which include intrinsic transverse momentum corresponding to a derivative with respect to the transverse coordinates. Its possible contribution to scattering processes is therefore of higher twist and vanishes in the forward limit. The relation of OAM to other twist 2 and 3 distributions known in the literature is derived and formalized by an unintegrated sum rule.
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