6533b854fe1ef96bd12addb5

RESEARCH PRODUCT

Measurement of the decay distribution of η′ → π+π−γ and evidence for the box anomaly

S. SpanierC. KoloH. MatthäyR. HackmannD. WaltherC.a. BakerF. WalterM. BenayounC. RegenfusU. StrohbuschC. StraßburgerK. PetersA. CooperL. MontanetB.s. ZouH. KalinowskyB. KalteyerJ. MeierJ. LüdemannK. BeuchertM. A. FaesslerI. ScottM. LakataS. ResagR.p. HaddockEberhard KlemptC.j. BattyD. JamnikD. EngelhardtT. KielC. PietraU. ThomaC. HoddP. SchmidtC. HoltzhaußenA. AbeleK.m. CroweHerbert KochJ. AdomeitW. DünnweberR. MccradyClaude AmslerMichael DoserM. HeinzelmannA. BerdozJ. BroseJ. KisielS. BischoffO. CramerPàl HidasG. PinterP. BlümJ. ReißmannC. N. PinderS. V. DombrowskiH. StöckT. CaseR. OuaredD.v. BuggM. HerzC. A. MeyerC. VölckerK. BrauneMarcel KunzeW. RoethelF. Ould-saadaM. TischhäuserT. DegenerN.p. HesseyB. KämmleN. DjaoshviliU. WiednerD. UrnerR. LanduaF.h. HeinsiusP. KammelB.m. BarnettM. SuffertR. SeibertP. Giarritta

subject

PseudoscalarPhysicsNuclear physicsQuantum chromodynamicsCrystalNuclear and High Energy PhysicsDistribution (mathematics)Anomaly (physics)Atomic physicsConstant (mathematics)

description

Abstract The distribution of m ( π + π − ) in the decay η ′ → π + π − γ has been measured with the Crystal Barrel detector. The results are based on a total of 7392 observed η′ decays. The box anomaly constant is extracted from this and its value is found to agree well with theoretical expectations. The pseudoscalar nonet parameters ( f 1 , f 8 and θ PS ) are determined. Finally, we find that there is a problem of consistency between QCD and the standard VDM assumption.

https://doi.org/10.1016/s0370-2693(97)00479-6