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arXiv · 0807.0011

Breakdown of the operator product expansion in the 't Hooft model

Jorge Mondejar·Antonio Pineda
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Abstract

We consider deep inelastic scattering in the 't Hooft model. Being solvable, this model allows us to directly compute the moments associated with the cross section at next-to-leading order in the 1/Q^2 expansion. We perform the same computation using the operator product expansion. We find that all the terms match in both computations except for one in the hadronic side, which is proportional to a non-local operator. The basics of the result suggest that a similar phenomenon may occur in four dimensions in the large N_c limit.

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Jorge Mondejar, Antonio Pineda. 2008-10-02. Breakdown of the operator product expansion in the 't Hooft model. https://doi.org/10.1103/physrevlett.101.152002

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