Precise Measurement of the Pi+ -> Pi0 e+ nu Branching Ratio
High Energy Physics - Experiment
2008-11-26 v2
Abstract
Using a large acceptance calorimeter and a stopped pion beam we have made a precise measurement of the rare Pi+ -> Pi0 e+ Nu,(pi_beta) decay branching ratio. We have evaluated the branching ratio by normalizing the number of observed pi_beta decays to the number of observed Pi+ -> e+ Nu, (pi_{e2}) decays. We find the value of Gamma(Pi+ -> Pi0 e+ Nu)/Gamma(total) = [1.036 +/- 0.004(stat.) +/- 0.004(syst.) +/- 0.003(pi_{e2})] x 10^{-8}$, where the first uncertainty is statistical, the second systematic, and the third is the pi_{e2} branching ratio uncertainty. Our result agrees well with the Standard Model prediction.
Cite
@article{arxiv.hep-ex/0312030,
title = {Precise Measurement of the Pi+ -> Pi0 e+ nu Branching Ratio},
author = {D. Pocanic and E. Frlez and V. A. Baranov and W. Bertl and C. Broennimann and M. Bychkov and J. F. Crawford and M. Daum and N. V. Khomutov and A. S. Korenchenko and S. M. Korenchenko and T. Kozlowski and N. P. Kravchuk and N. A. Kuchinsky and W. Li and R. C. Minehart and D. Mzhavia and B. G. Ritchie and S. Ritt and A. M. Rozhdestvensky and V. V. Sidorkin and L. C. Smith and I. Supek and Z. Tsamalaidze and B. A. VanDevender and Y. Wang and H. -P. Wirtz and K. O. H. Ziock},
journal= {arXiv preprint arXiv:hep-ex/0312030},
year = {2008}
}
Comments
4 pages, 5 figures, 1 table, revtex4; changed content; updated analysis