Tree-level soft emission of a quark pair in association with a gluon

Journal of High Energy Physics

Regular Article - Theoretical Physics

Claude Duhr¹  Zhengwen Liu²  Rayan Haindl³  Vittorio Del Duca⁴ 

[1] Bethe Center for Theoretical Physics, Universität Bonn, 53115, Bonn, Germany;Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607, Hamburg, Germany;Institute for Theoretical Physics, ETH Zürich, 8093, Zürich, Switzerland;Institute for Theoretical Physics, ETH Zürich, 8093, Zürich, Switzerland;Physik-Institut, Universität Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland;

关键词: Factorization;    Renormalization Group;    Higher-Order Perturbative Calculations;   

DOI  :  10.1007/JHEP01(2023)040

 received in 2022-06-23, accepted in 2022-12-22,  发布年份 2022

来源: Springer

【 摘 要 】

We compute the tree-level current for the emission of a soft quark-antiquark pair in association with a gluon. This soft current is the last missing ingredient to understand the infrared singularities that can arise in next-to-next-to-next-to-leading-order (N3LO) computations in QCD. Its square allows us to understand for the first time the colour correlations induced by the soft emission of a quark pair and a gluon. We find that there are three types of correlations: besides dipole-type correlations that have already appeared in soft limits of tree-level amplitudes, we uncover for the first time also a three-parton correlation involving a totally symmetric structure constant. We also study the behaviour of collinear splitting amplitudes in the triple-soft limit, and we derive the corresponding factorisation formula.

【 授权许可】

Unknown   
© The Author(s) 2023

【 图 表 】

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