Observation of the radiative decayJψ→e+e−γ

1 December 1996

journal article
research article
Published by American Physical Society (APS) in Physical Review D

Vol. 54 (11) , 7067-7070
https://doi.org/10.1103/physrevd.54.7067

Abstract

We report the first observation of the (radiative) decay

\frac{J}{ψ} \to e^{+} e^{-} γ

. Our data are from an experiment in which

\frac{J}{ψ}

is formed in antiproton-proton annihilations. The observed rate is consistent with a QED calculation based on final state radiation. Our measurement gives a branching ratio for this mode of (8.8±1.3±0.4)×

10^{- 3}

for

γ

energy>100 MeV.

Keywords

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