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arXiv · hep-ph/0406171

Sivers function in light-cone quark model and azimuthal spin asymmetries in pion electroproduction

Zhun Lu·Bo-Qiang Ma
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Abstract

We perform a calculation of Sivers function in a light-cone SU(6) quark-diquark model with both scalar diquark and vector diquark spectators. We derive the transverse momentum dependent light-cone wave function of the proton by taking into account the Melosh-Wigner rotation. By adopting one-gluon exchange, we obtain a non-vanishing Sivers function of $down$ quark from interference of proton spin amplitudes. We analyze the $\frac{|P_{h\perp}|}{M}$ weighted Sivers asymmetries in $π^+$, $π^-$ and $π^0$ electroproduction off transverse polarized proton target, averaged and not averaged by the kinematics of HERMES experiment.

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Zhun Lu, Bo-Qiang Ma. 2004-06-15. Sivers function in light-cone quark model and azimuthal spin asymmetries in pion electroproduction. https://doi.org/10.1016/j.nuclphysa.2004.06.006

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