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On the Calculation of the NLO Virtual Photon Impact Factor

V. S. Fadin·D. Yu. Ivanov·M. I. Kotsky
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Abstract

The definition of the virtual photon impact factor involves the integration of the s-channel discontinuity of the photon-Reggeon scattering amplitude over the right cut. It permits to formulate a new approach for the calculation of the impact factor based on analytical properties of the amplitude in question. In the next-to-leading order it may give a possibility for considerable simplification of the calculation. We have shown that a part of the diagrams contributing to the impact factor can be treated without their real calculation.

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V. S. Fadin, D. Yu. Ivanov, M. I. Kotsky. 2003-03-31. On the Calculation of the NLO Virtual Photon Impact Factor. https://doi.org/10.1016/s0550-3213(03)00219-0

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