Dalitz plot analyses of J /Ï\u88 â\u86\u92Ï\u80+Ï\u80-Ï\u800, J /Ï\u88 â\u86\u92k+K-Ï\u800, and J /Ï\u88 â\u86\u92 Ks0 K±Ï\u80â\u88\u93 produced via e+e- annihilation with initial-state radiation

摘要

We study the processes e+e-â\u86\u92γISRJ/Ï\u88, where J/Ï\u88â\u86\u92Ï\u80+Ï\u80-Ï\u800, J/Ï\u88â\u86\u92K+K-Ï\u800, and J/Ï\u88â\u86\u92KS0K±Ï\u80â\u88\u93 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 Ï\u92(nS) (n=2,3,4) resonances. We measure the ratio of branching fractions R1=B(J/Ï\u88â\u86\u92K+K-Ï\u800)B(J/Ï\u88â\u86\u92Ï\u80+Ï\u80-Ï\u800) and R2=B(J/Ï\u88â\u86\u92KS0K±Ï\u80â\u88\u93)B(J/Ï\u88â\u86\u92Ï\u80+Ï\u80-Ï\u800). We perform Dalitz plot analyses of the three J/Ï\u88 decay modes and measure fractions for resonances contributing to the decays. We also analyze the J/Ï\u88â\u86\u92Ï\u80+Ï\u80-Ï\u800 decay using the Veneziano model. We observe structures compatible with the presence of Ï\u81(1450) in all three J/Ï\u88 decay modes and measure the relative branching fraction: R(Ï\u81(1450))=B(Ï\u81(1450)â\u86\u92K+K-)B(Ï\u81(1450)â\u86\u92Ï\u80+Ï\u80-)=0.307±0.084(stat)±0.082(sys).