From a study of 2.7×106 J decays with the Mark III detector at the SLAC storage ring SPEAR, we have obtained new measurements of the two-body decays of the J into a vector and a pseudoscalar meson. We present branching ratios for decays to , KK*(892), , the previously unobserved modes , , , 0, 0, and new upper limits on 0 and 0. In the decay J+-, we observe 0- interference. The collection of measured branching ratios are simultaneously fit to a simple model of J decays which includes strong and electromagnetic amplitudes and allows for violation of SU(3) invariance. Using this model, we calculate the strange- and nonstrange-quark content of the and and conclude that (3518)% of the wave function can be attributed to an additional component, e.g., gluonium or radial excitation. The measurement of the 0 branching ratio, when combined with that of the 0 decay mode of the, yields a determination of the 0 electromagnetic-form-factor ratio f(q2=m 2)/f(q2=0) =0.0380.006.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)