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arXiv · 2607.05235

The variable flavor number scheme to three-loop order

J. Ablinger·A. Behring·J. Blümlein·A. De Freitas·A. von Manteuffel·C. Schneider·K. Schönwald
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Abstract

We describe the variable flavor number scheme to three-loop order, which modifies the massless parton densities by single- and two-mass effects and introduces heavy-quark parton distribution functions for charm and bottom. A renormalization group analysis shows the validity of this picture at large scales $Q^2$, where it resembles the non-power-suppressed heavy-flavor corrections completely. We also provide numerical implementations of a series of charged and neutral current Wilson coefficients.

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J. Ablinger, A. Behring, J. Blümlein, A. De Freitas, A. von Manteuffel, C. Schneider, K. Schönwald. 2026-07-06. The variable flavor number scheme to three-loop order. https://arxiv.org/abs/2607.05235

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