Heavy-quark contribution to the proton's magnetic moment

Xiangdong Ji; D. Toublan

doi:10.1016/j.physletb.2007.02.047

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arXiv · hep-ph/0605055

Heavy-quark contribution to the proton's magnetic moment

Xiangdong Ji·D. Toublan

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Abstract

We study the contribution to the proton's magnetic moment from a heavy quark sea in quantum chromodynamics. The heavy quark is integrated out perturbatively to obtain an effective dimension-6 magnetic moment operator composed of three gluon fields. The leading contribution to the matrix element in the proton comes from a quadratically divergent term associated with a light-quark tensor operator. With an approximate knowledge of the proton's tensor charge, we conclude that a heavy sea-quark contribution to the proton's magnetic moment is positive in the asymptotic limit. We comment on the implication of this result for the physical strange quark.

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Xiangdong Ji, D. Toublan. 2006-05-05. Heavy-quark contribution to the proton's magnetic moment. https://doi.org/10.1016/j.physletb.2007.02.047

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