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Twist-three observables in deeply virtual Compton scattering on the nucleon

A. V. Belitsky·A. Kirchner·D. Müller·A. Schäfer
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Abstract

We study twist-three effects in deeply virtual Compton scattering on an unpolarized spin-1/2 target. A careful definition of observables as Fourier moments w.r.t. the azimuthal angle allows for a clear separation of twist-two and -three effects. Although the latter are power suppressed, they give leading contributions to the twist-three asymmetries and do not affect the twist-two observables.

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A. V. Belitsky, A. Kirchner, D. Müller, A. Schäfer. 2001-05-09. Twist-three observables in deeply virtual Compton scattering on the nucleon. https://doi.org/10.1016/s0370-2693(01)00608-6

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