TheRratio in e+e-, the determination of α (MZ2) and a possible non-perturbative gluonic contribution
- 1 May 2000
- journal article
- Published by IOP Publishing in Journal of Physics G: Nuclear and Particle Physics
- Vol. 26 (5), 600-606
- https://doi.org/10.1088/0954-3899/26/5/313
Abstract
We review the determination of the QED coupling at the Z pole, which is a crucial parameter for electroweak theory. We include recent e+e-→ hadron data from Novosibirsk and Beijing to re-evaluate α(MZ2). We find α(MZ2)-1 = 128.973±0.035 or 128.934±0.040 according, respectively, to whether inclusive or exclusive e+e-→ hadron data are used respectively in the interval 1.4(s)1/22.1 GeV. The error is mainly due to uncertainties in the data in the low-energy region, (s)1/22.5 GeV. We find that no advantage is obtained by analytic continuation of the dispersion relation into the complex s plane. We show that the hints of structure for (s)1/2~2.5 GeV may be evidence of a non-perturbative gluonic contribution to R(s).Keywords
This publication has 26 references indexed in Scilit:
- a1(1260)π dominance in the process e+e−→4π at energies 1.05–1.38 GeVPhysics Letters B, 1999
- Testing non-perturbative strong interaction effects via the Adler functionPhysics Letters B, 1999
- Calculation of the QED coupling() in the modified minimal-subtraction schemePhysical Review D, 1999
- QCD sum rule determination of α(MZ) with minimal data inputPhysics Letters B, 1998
- A perturbation theory driven analysis of the effective QED coupling at MZPhysics Letters B, 1998
- New results on the hadronic contributions to α(MZ2) and to (g−2)μPhysics Letters B, 1998
- Leptonic contribution to the effective electromagnetic coupling constant up to three loopsPhysics Letters B, 1998
- Hadronic contributions to (g?2) of the leptons and to the effective fine structure constant ?(M Z 2 )The European Physical Journal C, 1995
- A determination of the QED coupling at the Z polePhysics Letters B, 1995
- Review of current algebra results in the weak decays of the metastable hadronsActa Physica Academiae Scientiarum Hungaricae, 1969