First Observation and Measurement of the Decay K+- -> pi+- e+ e- gamma
High Energy Physics - Experiment
2012-08-27 v1
Abstract
Using the full data set of the NA48/2 experiment, the decay K+- -> pi+- e+ e- gamma is observed for the first time, selecting 120 candidates with 7.3 +- 1.7 estimated background events. With K+- -> pi+- pi0D as normalisation channel, the branching ratio is determined in a model-independent way to be Br(K+- -> pi+- e+ e- gamma, m_eegamma > 260 MeV/c^2) = (1.19 +- 0.12_stat +- 0.04_syst) x 10^-8. This measured value and the spectrum of the e+ e- gamma invariant mass allow a comparison with predictions of Chiral Perturbation Theory.
Cite
@article{arxiv.0711.4313,
title = {First Observation and Measurement of the Decay K+- -> pi+- e+ e- gamma},
author = {2 Collaboration and J. R. Batley},
journal= {arXiv preprint arXiv:0711.4313},
year = {2012}
}
Comments
13 pages, 3 figures. Accepted for publication in Phys.Lett.B