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Updated: Jun 19, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Do gluons carry half of the nucleon momentum?
Xiang-Song Chen1, Wei-Min Sun, Xiao-Fu Lü
1Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, China.
Abstract:
We examine the conventional picture that gluons carry about half of the nucleon momentum in the asymptotic limit. We show that this large fraction is due to an unsuitable definition of the gluon momentum in an interacting theory. If defined in a gauge-invariant and consistent way, the asymptotic gluon momentum fraction is computed to be only about one-fifth. This result suggests that the asymptotic limit of the nucleon spin structure should also be reexamined. A possible experimental test of our finding is discussed in terms of novel parton distribution functions.
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