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arXiv · 2305.07129

Infrared Subtleties and Chiral Vertices at NLO: An Implicit Regularization Analysis

Ricardo J. C. Rosado·Adriano Cherchiglia·Marcos Sampaio·Brigitte Hiller
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Abstract

We employ implicit regularization (IReg) in quark-antiquark decays of the Z, or of a scalar (CP-even or odd) boson at NLO, and compare with dimensional schemes to reveal subtleties involving infrared divergence cancellation and $\gamma_5$-matrix issues. Besides the absence of evanescent fields in IReg, such as $\epsilon$-scalars required in certain schemes that operate partially in the physical dimension, we verify that our procedure preserves gauge invariance in the presence of the $\gamma_5$ matrix without requiring symmetry preserving counterterms while the amplitude is infrared finite as required by the KLN theorem.

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Ricardo J. C. Rosado, Adriano Cherchiglia, Marcos Sampaio, Brigitte Hiller. 2023-05-11. Infrared Subtleties and Chiral Vertices at NLO: An Implicit Regularization Analysis. https://doi.org/10.1140/epjc%2Fs10052-023-12052-2

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