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arXiv · 2410.21604

Transverse Orbital Angular Momentum in the Proton

Osamah Alkasassbeh·Abha Rajan·Michael Engelhardt·Simonetta Liuti
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Abstract

Using the equations of motion of QCD and Lorentz invariance relations, we show a new, more direct way of obtaining the decomposition of the proton's quark transverse angular momentum into its spin and orbital components. The new decomposition can be understood as a twist-three relation, with the quark transverse spin described by the parton distribution $g_T$. We find that the orbital component can be expressed in terms of a moment in the quark transverse momentum, $k_T$, of the generalized transverse momentum-dependent distribution $F_{12}$, or alternatively in terms of the twist-three generalized parton distributions $H_{2T}$ and $\widetilde{E}_{2T}$.

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Osamah Alkasassbeh, Abha Rajan, Michael Engelhardt, Simonetta Liuti. 2024-10-28. Transverse Orbital Angular Momentum in the Proton. https://arxiv.org/abs/2410.21604

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