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The Longitudinal Structure Function at the Third Order

S. Moch·J. A. M. Vermaseren·A. Vogt
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Abstract

We compute the complete third-order contributions to the coefficient functions for the longitudinal structure function F_L, thus completing the next-to-next-to-leading order (NNLO) description of unpolarized electromagnetic deep-inelastic scattering in massless perturbative QCD. Our exact results agree with determinations of low even-integer Mellin moments and of the leading small-x terms in the flavour-singlet sector. In this letter we present compact and accurate parametrizations of the results and illustrate the numerical impact of the NNLO corrections.

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S. Moch, J. A. M. Vermaseren, A. Vogt. 2004-11-09. The Longitudinal Structure Function at the Third Order. https://doi.org/10.1016/j.physletb.2004.11.063

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