Measurements by Belle Collaboration of the cross section for inclusive J/ψ production in e+e- annihilation have been a serious challenge to current heavy-quarkonium theory. In particular, the measured cross sections for exclusive J/ψ+ηc and inclusive J/ψ+cc̄+X differ from nonrelativistic QCD predictions by an order of magnitude. In order to check if other available alternative theories can resolve such a large discrepancy, we calculate the cross section for inclusive J/ψ+cc̄+X based on the color-evaporation model. As a phenomenological model, the color-evaporation model is still employed to predict cross sections for inclusive quarkonium production in various processes. Our results show that the color-evaporation- model prediction is even smaller than the nonrelativistic QCD prediction by an order of magnitude. The resultant color-evaporation-model prediction for the J/ψ+cc̄+X fraction in the inclusive J/ψ production cross section is 0.049, while the empirical value measured by Belle Collaboration is 0.82.
|Number of pages||5|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Publication status||Published - 2005 May 1|
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)