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Electron and photon structure functions at two loops

Schnubel, Marvin [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000218401377)·Szafron, Robert [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000296406923)
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Abstract

We present a fully analytic computation of the complete electron and photon structure functions, or QED lepton parton distribution functions (PDFs) up to two-loop order. Our computation is performed using modern techniques of reduction to Master Integrals and solving them with the differential equation method. We obtain explicit expressions for the electron-in-electron, positron-in-electron, photon-in-electron, electron-in-photon, and photon-in-photon distributions at next-to-next-to-leading order (NNLO). Cross-checks against one-loop results, existing two-loop calculations, and a recent soft-collinear effective theory (SCET) analysis of the electron structure functions are presented.

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSElectroweak Precision PhysicsPrecision QED

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Schnubel, Marvin [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000218401377), Szafron, Robert [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:0000000296406923). 2025-12-22. Electron and photon structure functions at two loops. https://doi.org/10.1007/jhep12(2025)167

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