QCD Sum Rules for Heavy-Meson Decay Constants: Impact of Renormalization Scale and Scheme

TL;DR

This paper investigates how the choice of renormalization scale and scheme affects QCD sum rule predictions for heavy-meson decay constants, focusing on charmed mesons, to improve the reliability of these nonperturbative calculations.

Contribution

It provides a detailed analysis of the impact of renormalization choices on QCD sum rule predictions for charmed meson decay constants, addressing discrepancies in previous approaches.

Findings

Renormalization scheme significantly influences decay constant predictions.

Adjusting the renormalization scale reduces uncertainties in sum rule calculations.

Results improve consistency with experimental data for charmed mesons.

Abstract

Within the realm of QCD sum rules, one of the most important areas of application of this nonperturbative approach is the prediction of the decay constants of heavy mesons. However, in spite of the fact that, indisputably, the adopted techniques are, of course, very similar, we encounter rather dissimilar challenges, or obstacles, when extracting from two-point correlators of appropriate heavy-light currents interpolating the mesons, the characteristics of charmed mesons with different spin. In view of this, it seems worthwhile to us to revisit this issue for the case of charmed pseudoscalar mesons $D_{(s)}$ and vector mesons $D^*_{(s)}.$