Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2009-06-30
Physics
High Energy Physics
High Energy Physics - Phenomenology
10 pages, 6 figures, submitted to Eur. Phys. J. C; (v2): Revised version with improved and uniform treatment of tau and e+e- d
Scientific paper
We revisit the procedure for comparing the pi pi spectral function measured in tau decays to that obtained in e+e- annihilation. We re-examine the isospin-breaking corrections using new experimental and theoretical input, and find improved agreement between the tau- --> pi- pi0 nu_tau branching fraction measurement and its prediction using the isospin-breaking-corrected e+e- --> pi+pi- spectral function, though not resolving all discrepancies. We recompute the lowest order hadronic contributions to the muon g-2 using e+e- and tau data with the new corrections, and find a reduced difference between the two evaluations. The new tau-based estimate of the muon magnetic anomaly is found to be 1.9 standard deviations lower than the direct measurement.
Castro Gabriel Lopez
Davier Michel
Hoecker Andreas
Malaescu Bogdan
Mo X. H.
No associations
LandOfFree
The Discrepancy Between tau and e+e- Spectral Functions Revisited and the Consequences for the Muon Magnetic Anomaly does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Discrepancy Between tau and e+e- Spectral Functions Revisited and the Consequences for the Muon Magnetic Anomaly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Discrepancy Between tau and e+e- Spectral Functions Revisited and the Consequences for the Muon Magnetic Anomaly will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-440448