Two-photon formation of the in the reaction e+e-e+e-me+e-+- has been studied for nearly real and virtual photons at an e+e- center-of-mass energy of 29 GeV. The width of the is found to be 4.50.3(stat.)0.7(syst.) keV. The measured dependence of this width upon the photon four-momentum squared in the range 05 GeV2 agrees with predictions both from QCD and from dominance. A spin analysis results in a strong preference for a spin-zero, relative to a spin-two, assignment for the . No evidence for C-parity violation is found in this +- decay mode.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)