6533b7d8fe1ef96bd12698f6

RESEARCH PRODUCT

A measurement of the decay KL→π0γγ

I. MannelliB. PanzerM. RostKonrad KleinknechtM. HolderH.h. NelsonO. PerdereauArthur SchafferR. HagelbergR. CarosiA. WagnerLaurent SerinB. RenkI. HarrusP. GrafströmG.d. BarrLydia Iconomidou-fayardL. BertanzaR. WerthenbachA. KreutzV.m. MarzulliH. D. WahlD.c. CundyM. CalvettiR. CasaliP. MayerR. HeinzA. NappiNiels DobleG.m. PierazziniPeter BuchholzH. BlümerA. BigiL. GatignonD. CowardE. AugePaolo CalafiuraKen PeachDaniel FournierH. Rohrer

subject

PhysicsNuclear and High Energy PhysicsParticle physicsPhotonChiral perturbation theoryMeson010308 nuclear & particles physicsBranching fractionElementary particle7. Clean energy01 natural sciencesNuclear physicsParticle decay0103 physical sciencesHigh Energy Physics::ExperimentInvariant mass010306 general physicsBoson

description

Abstract The full data set of the experiment NA31 at CERN has been used to analyse the decay mode KL→π0γγ. A signal of 63 events has been observed with an estimated background of 6.0±1.7 events, corresponding to a branching ratio of (1.7±0.3)×10−6 consistent with our previous result based on partial statistics. The invariant mass spectrum of the two photons is found to be consistent with chiral perturbation theory, and the decay is dominated by the J = 0 two photon state.

yearjournalcountryeditionlanguage
1992-06-01Physics Letters B
https://doi.org/10.1016/0370-2693(92)90458-g