https://doi.org/10.1140/epjc/s10052-020-7873-2
Regular Article - Theoretical Physics
The studies on 
at the next-to-leading-order QCD accuracy
Department of Physics, Guizhou Minzu University, Guiyang, 550025, People’s Republic of China
* e-mail: zhansun@cqu.edu.cn
Received:
10
February
2020
Accepted:
24
March
2020
Published online:
8
April
2020
In this paper, we carry out the next-to-leading-order (NLO) studies on via the color-singlet (CS) 
state. We find the newly calculated NLO QCD corrections to this process can significantly influence its leading-order (LO) results and greatly improve the dependence on the renormalization scale. By including the considerable feeddown contributions, the branching ratio 
is predicted to be (0.56–0.95) 
, which can reach up to 19–31
of the LO predictions given by the CS dominant process 
. Moreover, also seriously affects the CS predictions on the 
energy distributions, especially when z is relatively small. In summary, for the inclusive productions in Z decay, besides , the gluon radiation process can provide indispensable contributions as well.
© The Author(s), 2020
