The properties of $C$-parameter and coupling constants

Pramana

M E ZOMORRODIAN1¹  R SALEH-MOGHADDAM¹ 

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

关键词: Quantum chromodynamics;    perturbative calculations;    non-perturbative theory.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

We present the properties of the C-parameter as an event-shape variable. We calculate the coupling constants in the perturbative and also in the non-perturbative parts of the QCD theory, using the dispersive as wellas the shape function models. By fitting the corresponding theoretical predictions to our data, we find $alpha_{s}(M_{Z^{0}} ) = 0.117 pm 0.014$ and $alpha_{0}(mu_{I} ) = 0.491 pm 0.043$ for dispersive model and $alpha_{ s}(M_{Z^{0}} ) = 0.124 pm 0.015$ and $lambda_{1} = 1.234 pm 0.052$ for the shape function model. Our results are consistent with the world average value of $alpha_{s}(M_{Z^{0}} ) = 0.118 pm 0.002$. All these features are explained in the main text.

【 授权许可】

Unknown