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arXiv · hep-ph/9710247

The Quark Spin Distributions of the Nucleon

Bo-Qiang Ma·Ivan Schmidt·Jacques Soffer
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Abstract

The quark helicity measured in polarized deep inelastic scattering is different from the quark spin in the rest frame of the nucleon. We point out that the quark spin distributions $Δq_{RF}(x)$ are connected with the quark helicity distributions $Δq(x)$ and the quark transversity distributions $δq(x)$ by an approximate relation: $Δq_{RF}(x) + Δq(x)=2 δq(x)$. This relation will be useful in order to measure the rest frame (or quark model) spin distributions of the nucleon once the quark helicity distributions and quark transversity distributions are themselves measured. We also calculate the $x$-dependent quark transversity distributions $δq(x)$ and quark spin distributions $Δq_{RF}(x)$ in a light-cone SU(6) quark-spectator model, and present discussions on possible effect from the sea quark-antiquark pairs.

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Bo-Qiang Ma, Ivan Schmidt, Jacques Soffer. 1998-09-16. The Quark Spin Distributions of the Nucleon. https://doi.org/10.1016/s0370-2693(98)01158-7

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