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If sea-quark Sivers asymmetry is non-zero, then sea quarks have non-zero OAM.
A non-zero Sivers asymmetry from SpinQuest is "smoking gun" evidence for sea quark OAM
SpinQuest will measure the correlation between the angular distribution of the di-muons and the proton spin. If this is non-zero, then the antiquarks must have some orbital angular momentum.
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