With the E731 apparatus at Fermilab, we have simultaneously collected 6859 KL and KS decays into π+π-γ. Using our sample of over 370 000 π+π- decays for normalization we have determined that the ratio Γ(K0→π+π-γ)/Γ(K0→π+π-) is (23.0±0.7)×10-3 for KL and (7.10±0.22)×10-3 for KS, for photon energies greater than 20 MeV in the kaon center of mass. After removing the inner-bremsstrahlung contribution, we find that the photon energy spectrum of the direct emission decay of the KL is consistent with the presence of a vector meson propagator in the form factor.
ASJC Scopus subject areas
- Physics and Astronomy(all)