TY  - JOUR
AU  - Pich, A.
AU  - Rodriguez-Sanchez, A.
PY  - 2016
DA  - 2016//
TI  - Determination of the QCD coupling from ALEPH tau decay data
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 034027
EP  - 26pp
VL  - 94
IS  - 3
PB  - Amer Physical Soc
AB  - We present a comprehensive study of the determination of the strong coupling from tau decay, using the most recent release of the experimental ALEPH data. We critically review all theoretical strategies used in previous works and put forward various novel approaches which allow one to study complementary aspects of the problem. We investigate the advantages and disadvantages of the different methods, trying to uncover their potential hidden weaknesses and test the stability of the obtained results under slight variations of the assumed inputs. We perform several determinations, using different methodologies, and find a very consistent set of results. All determinations are in excellent agreement, and allow us to extract a very reliable value for alpha(s)(m(tau)(2)). The main uncertainty originates in the pure perturbative error from unknown higher orders. Taking into account the systematic differences between the results obtained with the contour-improved perturbation theory and fixed-order perturbation theory prescriptions, we find alpha((nf=3))(s) (m(tau)(2)) = 0.328 +/- 0.013 which implies alpha((nf=5))(s) (M-Z(2)) = 0.1197 +/- 0.0015.
SN  - 2470-0010
UR  - http://arxiv.org/abs/1605.06830
UR  - https://doi.org/10.1103/PhysRevD.94.034027
DO  - 10.1103/PhysRevD.94.034027
LA  - English
N1  - WOS:000381413500001
ID  - Pich+Rodriguez-Sanchez2016
ER  -