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arXiv · hep-ph/9801369

Helicity-Flip Off-Foward Parton Distributions of the Nucleon

Pervez Hoodbhoy·Xiangdong Ji
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Abstract

We identify quark and gluon helicity-flip distributions defined between nucleon states of unequal momenta. The evolution of these distributions with change of renormalization scale is calculated in the leading-logarithmic approximation. The helicity-flip gluon distributions do not mix with any quark distribution and are thus a unique signature of gluons in the nucleon. Their contribution to the generalized virtual Compton process is obtained both in the form of a factorization theorem and an operator product expansion. In deeply virtual Compton scattering, they can be probed through distinct angular dependence of the cross section.

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Pervez Hoodbhoy, Xiangdong Ji. 1998-02-13. Helicity-Flip Off-Foward Parton Distributions of the Nucleon. https://doi.org/10.1103/physrevd.58.054006

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