TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhysProc.1.049
TI  - Renormalization-group improvement in hadronic $τ$ decays in 2018
PY  - 2019/02/22
UR  - https://scipost.org/SciPostPhysProc.1.049
JF  - SciPost Physics Proceedings
JA  - SciPost Phys. Proc.
VL  - 
IS  - 1
SP  - 049
A1  - Boito, Diogo
AU  - Masjuan, Pere
AU  - Oliani, Fabio
AB  - One of the main sources of theoretical uncertainty in the extraction of the strong coupling from hadronic tau decays stems from the renormalization group improvement of the series. Perturbative series in QCD are divergent but are (most likely) asymptotic expansions. One needs knowledge about higher orders to be able to choose the optimal renormalization-scale setting procedure. Here, we discuss the use of Pad\'e approximants as a model-independent and robust method to extract information about the higher-order terms. We show that in hadronic \boldmath $\tau$ decays the fixed-order expansion, known as fixed-order perturbation theory (FOPT), is the most reliable mainstream method to set the scale. This fully corroborates previous conclusions based on the available knowledge about the leading renormalon singularities of the perturbative series.
ER  -

@Article{10.21468/SciPostPhysProc.1.049,
	title={{Renormalization-group improvement in hadronic $τ$ decays in 2018}},
	author={Diogo Boito and Pere Masjuan and Fabio Oliani},
	journal={SciPost Phys. Proc.},
	pages={049},
	year={2019},
	publisher={SciPost},
	doi={10.21468/SciPostPhysProc.1.049},
	url={https://scipost.org/10.21468/SciPostPhysProc.1.049},
}