The decay rate of the neutral K meson KL → e+e-γ has been measured with the NA48 detector at the CERN SPS. A total of 6864 events has been observed with an estimated background of 10 events. The branching ratio is Γ(KL → e+e-γ)/Γ(KL → all) = (1.06 ± 0.02stat ± 0.02sys ± 0.04calc) × 10-5 The parameter αK* describing the relative strength of the two contributing amplitudes to this decay through intermediate pseudoscalar or vector mesons was measured to be αK* = -0.36 ± 0.06stat ± 0.02sys.
|Original language||English (US)|
|Number of pages||11|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - 1999|
ASJC Scopus subject areas
- Nuclear and High Energy Physics