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Moments of generalized parton distribution functions and the nucleon spin contents

M. Wakamatsu
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Abstract

It is shown that, based only on two empirically known facts besides two reasonable theoretical postulates, we are inevitably led to a conclusion that the quark orbital angular momentum carries nearly half of the total nucleon spin. We also perform a model analysis to find that the quark spin fraction $ΔΣ$ is extremely sensitive to the pion mass, which may resolve the discrepancy between the observation and the prediction of the recent lattice QCD simulation carried out in the heavy pion region.

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M. Wakamatsu. 2005-06-09. Moments of generalized parton distribution functions and the nucleon spin contents. https://doi.org/10.1103/physrevd.72.074006

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