Year: 1985
Type: article
Abstract: From a study of 2.7\ifmmode\times\else\texttimes\fi{}${10}^{6}$ J/\ensuremath{\psi} 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/\ensuremath{\psi} into a vector and a pseudoscalar meson. We present branching ratios for decays to \ensuremath{\rho}\ensuremath{\pi}, ${\mathrm{KK}}^{\mathrm{*}}$(892), \ensuremath{\varphi}\ensuremath{\eta}, the previously unobserved modes \ensuremath{\varphi}\ensuremath{\eta}', \ensuremath{\omega}\ensuremath{\eta}, \ensuremath{\omega}\ensuremath{\eta}', \ensuremath{\omega}${\ensuremath{\pi}}^{0}$, ${\ensuremath{\rho}}^{0}$\ensuremath{\eta}, and new upper limits on ${\ensuremath{\rho}}^{0}$\ensuremath{\eta}' and \ensuremath{\varphi}${\ensuremath{\pi}}^{0}$. In the decay J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\eta}${\ensuremath{\pi}}^{+}$${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$, we observe ${\ensuremath{\rho}}^{0}$-\ensuremath{\omega} interference. The collection of measured branching ratios are simultaneously fit to a simple model of J/\ensuremath{\psi} decays which includes strong and electromagnetic amplitudes and allows for violation of SU(3) invariance. Using this model, we calculate the strange- and nonstrange-quark content of the \ensuremath{\eta} and \ensuremath{\eta}' and conclude that (35\ifmmode\pm\else\textpm\fi{}18)% of the \ensuremath{\eta}' wave function can be attributed to an additional component, e.g., gluonium or radial excitation. The measurement of the \ensuremath{\omega}${\ensuremath{\pi}}^{0}$ branching ratio, when combined with that of the \ensuremath{\gamma}${\ensuremath{\pi}}^{0}$ decay mode of the \ensuremath{\omega}, yields a determination of the \ensuremath{\omega}${\ensuremath{\pi}}^{0}$ electromagnetic-form-factor ratio \ensuremath{\Vert}f(${q}^{2}$=${m}_{J/\ensuremath{\psi}}$${\mathrm{}}^{2}$)/f(${q}^{2}$=0) \ensuremath{\Vert}=0.038\ifmmode\pm\else\textpm\fi{}0.006.
Authors: R. M. Baltrusaitis, D. Coffman, J. Hauser, D. G. Hitlin, J. D. Richman, J. J. Russell, R. H. Schindler, D. E. Dorfan, R. Fabrizio, F. Grancagnolo, R. P. Hamilton, C. A. Heusch, L. Köpke, R. Partridge, J. Perrier, H. F. W. Sadrozinski, M. Scarlatella, T. L. Schalk, A. Seiden, J. J. Becker, G. T. Blaylock, J. S. Brown, H. Cui, B. I. Eisenstein, G. Gladding, S. A. Plaetzer, A. L. Spadafora, J. J. Thaler, A. Wattenberg, W. J. Wisniewski, K. O. Bunnell, R. E. Cassell, D. H. Coward, K. F. Einsweiler, L. Moss, R. F. Mozley, A. Odian, J. R. Roehrig, W. Toki, Y. Unno, F. Villa, N. Wermes, D. Wisinski, T. H. Burnett, V. Cook, C. Del Papa, A. L. Duncan, P. M. Mockett, A. Nappi, J. C. Sleeman, H. J. Willutzki
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Award: G2371548206
OpenAlex ID: W82718921