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Testing the theory of the strong force by measuring proton spin polarizabilities

Measurements of a transversely polarized target were used to probe the spin structure of the proton in the low-energy region where the interactions between the quarks cannot be ignored. These results provide a benchmark for testing our understanding of the strong force.

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Fig. 1: Comparing the measured generalized transverse–longitudinal spin polarizability of the proton with the results of theoretical calculations.

References

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This is a summary of: Ruth, D. et al. Proton spin structure and generalized polarizabilities in the strong quantum chromodynamics regime. Nat. Phys. https://doi.org/10.1038/s41567-022-01781-y (2022).

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Testing the theory of the strong force by measuring proton spin polarizabilities. Nat. Phys. 18, 1406–1407 (2022). https://doi.org/10.1038/s41567-022-01783-w

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