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arXiv · 2010.13451

Potential linear and angular momentum in the scalar diquark model

David Arturo Amor-Quiroz·Matthias Burkardt·William Focillon·Cédric Lorcé
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Abstract

We present an analytic two-loop calculation within the scalar diquark model of the potential linear and angular momenta, defined as the difference between the Jaffe-Manohar and Ji notions of linear and angular momenta. As expected by parity and time-reversal symmetries, a direct calculation confirms that the potential transverse momentum coincides with the Jaffe-Manohar (or canonical) definition of average quark transverse momentum, also known as the quark Sivers shift. We examine whether initial/final-state interactions at the origin of the Sivers asymmetry can also generate a potential angular momentum in the scalar diquark model.

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David Arturo Amor-Quiroz, Matthias Burkardt, William Focillon, Cédric Lorcé. 2020-10-26. Potential linear and angular momentum in the scalar diquark model. https://doi.org/10.1140/epjc%2Fs10052-021-09345-9

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