J/psi decays into a vector and a pseudoscalar meson and the quark content of the eta and eta'
From a study of 2.7 x 10/sup 6/ J/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/psi into a vector and a pseudoscalar meson. We present branching ratios for decays to rho..pi.., KK((892), phieta, the previously unobserved modes phieta', ..omega..eta, ..omega..eta', ..omega pi../sup 0/, rho/sup 0/eta, and new upper limits on rho/sup 0/eta' and phi..pi../sup 0/. In the decay J/psi..-->..eta..pi../sup +/..pi../sup -/, we observe rho/sup 0/-..omega.. interference. The collection of measured branching ratios are simultaneously fit to a simple model of J/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 eta and eta' and conclude that (35 +- 18)% of the eta' wave function can be attributed to an additional component, e.g., gluonium or radial excitation. The measurement of the ..omega pi../sup 0/ branching ratio, when combined with that of the ..gamma pi../sup 0/ decay mode of the ..omega.., yields a determination of the ..omega pi../sup 0/ electromagnetic-form-factor ratio Vertical Barf(q/sup 2/ = m/sub J/psi/ /sup 2/)/f(q/sup 2/ = 0) Vertical Bar = 0.038 +- 0.006.
- Research Organization:
- California Institute of Technology, Pasadena, California 91125
- DOE Contract Number:
- AC03-76SF00515; AC02-76ER01195; AC03-81ER40050; AA03-76SF00034
- OSTI ID:
- 6237801
- Journal Information:
- Phys. Rev. D; (United States), Journal Name: Phys. Rev. D; (United States) Vol. 32:11; ISSN PRVDA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Measurements of J/psi decays into a vector and a pseudoscalar meson
Decays of the J/psi into two pseudoscalar mesons
Related Subjects
645104* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Strong Meson-Induced Interactions-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOSONS
BRANCHING RATIO
COMPOSITE MODELS
DECAY
ELECTROMAGNETIC FORM FACTORS
ELEMENTARY PARTICLES
ETA MESONS
ETA-958 RESONANCES
FORM FACTORS
FUNCTIONS
GLUONS
HADRONIC PARTICLE DECAY
HADRONS
LIE GROUPS
MANY-BODY PROBLEM
MATHEMATICAL MODELS
MESON RESONANCES
MESONS
MONTE CARLO METHOD
OMEGA-784 RESONANCES
PARTICLE DECAY
PARTICLE MODELS
PARTICLE PROPERTIES
PARTICLE STRUCTURE
PHI-1019 RESONANCES
PIONS
POSTULATED PARTICLES
PSEUDOSCALAR MESONS
PSI RESONANCES
QUANTUM NUMBERS
QUARK MODEL
RESONANCE PARTICLES
SPEAR
STORAGE RINGS
SU GROUPS
SU-3 GROUPS
SYMMETRY GROUPS
TWO-BODY PROBLEM
VECTOR MESONS
WAVE FUNCTIONS