Linear power corrections to e+e– shape variables in the three-jet region

Journal of High Energy Physics

Regular Article - Theoretical Physics

Giovanni Limatola¹  Paolo Nason²  Kirill Melnikov³  Melih Arslan Ozcelik³  Silvia Ferrario Ravasio⁴  Fabrizio Caola⁵ 

[1] INFN, Sezione di Milano-Bicocca, and Università di Milano-Bicocca, Piazza della Scienza 3, 20126, Milano, Italy;INFN, Sezione di Milano-Bicocca, and Università di Milano-Bicocca, Piazza della Scienza 3, 20126, Milano, Italy;Max-Planck-Institut für Physik, 80805, München, Germany;Institute for Theoretical Particle Physics, KIT, 76128, Karlsruhe, Germany;Rudolf Peierls Centre for Theoretical Physics, Clarendon Laboratory, University of Oxford, Parks Road, OX1 3PU, Oxford, U.K.;Rudolf Peierls Centre for Theoretical Physics, Clarendon Laboratory, University of Oxford, Parks Road, OX1 3PU, Oxford, U.K.;Wadham College, Parks Road, OX1 3PN, Oxford, U.K.;

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

DOI  :  10.1007/JHEP12(2022)062

 received in 2022-05-31, accepted in 2022-11-01,  发布年份 2022

来源: Springer

【 摘 要 】

We use an abelian model to study linear power corrections which arise from infrared renormalons and affect event shapes in e+e− annihilation into hadrons. While previous studies explored power corrections in the two-jet region, in this paper we focus on the three-jet region, which is the most relevant one for the determination of the strong coupling constant. We show that for a broad class of shape variables, linear power corrections can be written in a factorised form, that involves an analytically-calculable function, that characterises changes in the shape variable when a soft parton is emitted, and a constant universal factor. This universal factor is proportional to the so-called Milan factor, introduced in earlier literature to describe linear power corrections in the two-jet region. We find that the power corrections in the two-jet and in the three-jet regions are different, a result which is bound to have important consequences for the determination of the strong coupling constant from event shapes. As a further illustration of the power of the approach developed in this paper, we provide explicit analytic expressions for the leading power corrections to the C-parameter and the thrust distributions in the N -jet region for arbitrary N, albeit in the abelian model.

【 授权许可】

Unknown   
© The Author(s) 2022