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Proton spin structure and valence quarks

Petr Zavada
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Abstract

The spin structure of the system of quasifree fermions having total angular momentum $J=1/2$ is studied in a consistently covariant approach. Within this model the relations between the spin functions are obtained. Their particular cases are the sum rules Wanzura - Wilczek, Efremov - Leader - Teryaev, Burkhardt - Cottingham and also the expression for the Wanzura - Wilczek twist 2 term $g_{2}^{WW}$. With the use of the proton valence quark distributions as an input, the corresponding spin functions are obtained. The resulting structure functions $g_{1}$ and $g_{2}$ are well compatible with the experimental data.

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Petr Zavada. 2002-11-27. Proton spin structure and valence quarks. https://doi.org/10.1103/physrevd.67.014019

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