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arXiv · 1712.00745

The massive 3-loop operator matrix elements with two masses and the generalized variable flavor number scheme

J. Ablinger·J. Blümlein·A. De Freitas·A. Goedicke·C. Schneider·K. Schönwald·F. Wißbrock
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Abstract

We report on our latest results in the calculation of the two--mass contributions to 3--loop operator matrix elements (OMEs). These OMEs are needed to compute the corresponding contributions to the deep-inealstic scattering structure functions and to generalize the variable flavor number scheme by including both charm and bottom quarks. We present the results for the non-singlet and $A_{gq,Q}$ OMEs, and compare the size of their contribution relative to the single mass case. Results for the gluonic OME $A_{gg,Q}$ are given in the physical case, going beyond those presented in a previous publication where scalar diagrams were computed. We also discuss our recently published two--mass contribution to the pure singlet OME, and present an alternative method of calculating the corresponding diagrams.

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J. Ablinger, J. Blümlein, A. De Freitas, A. Goedicke, C. Schneider, K. Schönwald, F. Wißbrock. 2017-12-03. The massive 3-loop operator matrix elements with two masses and the generalized variable flavor number scheme. https://arxiv.org/abs/1712.00745

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