English

Measurement of the K_L -> e+ e- e+ e- Decay Rate

High Energy Physics - Experiment 2009-10-31 v2

Abstract

The decay rate of the neutral long-lived K meson into the e+ e- e+ e- final state has been measured with the NA48 detector at the CERN SPS. Using data collected in 1999, a total of 132 events has been observed with negligible background. The total number of kaons was determined to be 5.1 x 10^10. This observation corresponds to a preliminary branching ratio of Gamma(K_L -> e+ e- e+ e-)/Gamma(K_L -> all) = (3.67 +- 0.32(stat) +- 0.23(sys) +- 0.08(norm)) x 10^-8, where the first error is statistical, the second systematic, and the third error is due to the uncertainty in the normalization.

Keywords

Cite

@article{arxiv.hep-ex/0006040,
  title  = {Measurement of the K_L -> e+ e- e+ e- Decay Rate},
  author = {A. Lai},
  journal= {arXiv preprint arXiv:hep-ex/0006040},
  year   = {2009}
}

Comments

LaTeX, 10 pages, 4 Figures. Fig. 2 corrected (wrong cut shape before). Contributed paper # 229 to ICHEP 2000, Osaka

R2 v1 2026-07-22T12:58:28.741Z