Production of chi (c2) mesons in photon-photon collisions at LEP

We present an observation at LEP of the production of chi_c2 mesons in the collisions of two quasi-real photons using the OPAL detector. The chi_c2 mesons are reconstructed in the decay channel Chi_c2 to J/psi gamma to l+l- gamma (with l= e,mu) using all data taken at e+e- centre-of-mass energies of 91 and 183 GeV, corresponding to integrated luminosities of 167 and 55 pb-1 respectively. The two-photon width of the Chi_2 is determined to be 1.76 +- 0.47 +- 0.37 +- 0.15 keV where the first error is statistical, the second is systematic and the third comes from branching ratio uncertainties.

Note:

18 pages, LaTeX, 6 eps figures included, submitted to Physics Letters B Report-no: CERN-EP/98-106

electron positron: colliding beams
exchange: two-photon
photon photon: interaction
chi/c2(3555): photoproduction
chi/c2(3555): radiative decay
chi/c2(3555): width
OPAL
experimental results
CERN LEP Stor
electron positron --> chi/c2(3555) positron electron

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