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Quark model predictions for the SU(6)-breaking ratio of the proton momentum distributions

M. M. Giannini·E. Santopinto·A. Vassallo·M. Vanderhaeghen
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Abstract

The ratio between the anomalous magnetic moments of proton and neutron has been recently parametrized by the ratio of proton momentum fractions $M_{2}^{q_{val}}$. This ratio is evaluated using different constituent quark models, starting from the CQM density distributions and calculating the next-to leading order distributions. We show that this momentum fractions $M_{2}^{q_{val}}$ ratio is a sensitive test for SU(6)-breaking effects and therefore it is useful to distinguish among different CQMs. We investigate also the possibility of getting constraints on the formulation of quark structure models.

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M. M. Giannini, E. Santopinto, A. Vassallo, M. Vanderhaeghen. 2002-12-05. Quark model predictions for the SU(6)-breaking ratio of the proton momentum distributions. https://doi.org/10.1016/s0370-2693(02)03158-1

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