Next-to-next-to-leading order calculation of the strong coupling constant 𝛼𝑠by using moments of event-shape variables

Pramana

Mohammad Ebrahim Zomorrodian¹  Samira Shoeibi Mohsenabadi1¹ 

[1] Department of Physics, Ferdowsi University of Mashhad, Mashhad 91775-1436, Iran$$

关键词: Event shape;    quantum chromodynamics;    next-to-next-to-leading order correction.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

The next-to-next-to-leading order (NNLO) quantum chromodynamics (QCD) correction to the first three moments of the four event-shape variables in electron–positron annihilation, the thrust, heavy jet mass, wide, and total jet broadening, is computed. It is observed that the NNLO correction gives a better agreement between the theory and the experimental data. Also, by using the above observables, the strong coupling constant (𝛼𝑠) is determined and how much its value is affected by the NNLO correction is demonstrated. By combining the results for all variables at different centre-of-mass energies 𝛼𝑠 $(M_{Z^{°}})$ = 0.1248 ± 0.0009 $({ext{exp.}})_{-0.0144}^{+0.0283} ({ext{theo.}})$ is obtained.

【 授权许可】

Unknown