First Observation of the Rare Decay Mode K-long -> e+ e-
High Energy Physics - Experiment
2008-11-26 v1
Abstract
In an experiment designed to search for and study very rare two-body decay modes of the K-long, we have observed four examples of the decay K-long -> e+ e-, where the expected background is 0.17+-0.10 events. This observation translates into a branching fraction of 8.7^{+5.7}_{-4.1} X 10^{-12}, consistent with recent theoretical predictions. This result represents by far the smallest branching fraction yet measured in particle physics.
Cite
@article{arxiv.hep-ex/9810007,
title = {First Observation of the Rare Decay Mode K-long -> e+ e-},
author = {BNL E871 Collaboration and D. Ambrose and C. Arroyo and M. Bachman and P. de Cecco and D. Connor and M. Eckhause and K. M. Ecklund and S. Graessle and A. D. Hancock and K. Hartman and M. Hebert and C. H. Hoff and G. W. Hoffmann and G. M. Irwin and J. R. Kane and N. Kanematsu and Y. Kuang and K. Lang and R. Lee and R. D. Martin and J. McDonough and A. Milder and W. R. Molzon and M. Pommot-Maia and P. J. Riley and J. L. Ritchie and P. D. Rubin and V. I. Vassilakopoulos and C. B. Ware and R. E. Welsh and S. G. Wojcicki and E. Wolin and S. Worm},
journal= {arXiv preprint arXiv:hep-ex/9810007},
year = {2008}
}
Comments
9 pages, 3 figures