Eur. Phys. J. C (2018) 78: 61
https://doi.org/10.1140/epjc/s10052-018-5560-3

Regular Article - Theoretical Physics

The decays into light hadrons using the principle of maximum conformality

Department of Physics, Chongqing University, Chongqing, 401331, People’s Republic of China

^* e-mail: wuxg@cqu.edu.cn

Received: 9 December 2017
Accepted: 13 January 2018
Published online: 23 January 2018

Abstract

In the paper, we analyze the decays into light hadrons at the next-to-leading order QCD corrections by applying the principle of maximum conformality (PMC). The relativistic correction at the -order level has been included in the discussion, which gives about contribution to the ratio R. The PMC, which satisfies the renormalization group invariance, is designed to obtain a scale-fixed and scheme-independent prediction at any fixed order. To avoid the confusion of treating -terms, we transform the usual pQCD series into the one under the minimal momentum space subtraction scheme. To compare with the prediction under conventional scale setting, , after applying the PMC, we obtain , where the errors are squared averages of the ones caused by and . The PMC prediction agrees with the recent PDG value within errors, i.e. . Thus we think the mismatching of the prediction under conventional scale-setting with the data is due to improper choice of scale, which however can be solved by using the PMC.