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arXiv · hep-ph/0210430

Three-Quark Light-Cone Amplitudes of The Proton And Quark-Orbital-Motion Dependent Observables

Xiangdong Ji·Jian-Ping Ma·Feng Yuan
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Abstract

We study the three-quark light-cone amplitudes of the proton including quarks' transverse momenta. We classify these amplitudes using a newly-developed method in which light-cone wave functions are constructed from a class of light-cone matrix elements. We derive the constraints on the amplitudes from parity and time-reversal symmetries. We use the amplitudes to calculate the physical observables which vanish when the quark orbital angular momentum is absent. These include transverse-momentum dependent parton distributions $Δq_T(x, k_\perp)$, $q_T(x, k_\perp)$, $δq(x, k_\perp)$, and $δq_L(x,k_\perp)$, twist-three parton distributions $g_T(x)$ and $h_L(x)$, helicity-flip generalized parton distributions $E(x, ξ=0, Q^2)$ and its associates, and the Pauli form factor $F_2(Q^2)$.

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Xiangdong Ji, Jian-Ping Ma, Feng Yuan. 2002-10-30. Three-Quark Light-Cone Amplitudes of The Proton And Quark-Orbital-Motion Dependent Observables. https://doi.org/10.1016/s0550-3213(03)00010-5

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