We study the processes γγ→KS0K±πℓ and γγ→K+K-π0 using a data sample of 519 fb-1 recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e+e- collider at center-of-mass energies at and near the Υ(nS) (n=2, 3, 4) resonances. We observe ηc decays to both final states and perform Dalitz plot analyses using a model-independent partial wave analysis technique. This allows a model-independent measurement of the mass-dependence of the I=1/2 Kπ S-wave amplitude and phase. A comparison between the present measurement and those from previous experiments indicates similar behavior for the phase up to a mass of 1.5 GeV/c2. In contrast, the amplitudes show very marked differences. The data require the presence of a new a0(1950) resonance with parameters m=1931±14±22 MeV/c2 and Γ=271±22±29 MeV.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics