Observation of double c anti-c production in e+ e- annihilation at s**(1/2) approximately 10.6-GeV
May, 20027 pages
Published in:
- Phys.Rev.Lett. 89 (2002) 142001
e-Print:
- hep-ex/0205104 [hep-ex]
Report number:
- BELLE-PREPRINT-2002-13,
- KEK-PREPRINT-2002-27
Experiments:
View in:
Citations per year
Abstract: (arXiv)
We report the observation of prompt J/psi via double ccbar production from the e+e- continuum. In this process one ccbar pair fragments into a J/psi meson while the remaining pair either produces a bound charmonium state or fragments into open charm. Both cases have been observed: the first by studying the mass spectrum of the system recoiling against the J/psi, and the second by reconstructing the J/psi together with a charmed meson. We find cross-sections of \sigma(e+ e- -> J/psi eta_c (gamma)) * BR (eta_c -> >=4 charged) = 0.033 (+0.007 -0.006)(stat) \pm 0.009(syst)pb and \sigma(e+ e- -> J/psi D*+ X) = 0.53 (+0.19 -0.15)(stat) \pm 0.14(syst) pb, and infer \sigma(e+ e- -> J/psi c cbar) / \sigma(e+ e- -> J/psi X) = 0.59 (+0.15 -0.13)(stat) \pm 0.12(syst). These results are obtained from a 46.2/fb data sample collected near the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric energy e+ e- collider.Note:
- 7 pages, 2 figures, to be submitted to Physical Review Letters Report-no: KEK Preprint 2002-27, Belle Preprint 2002-13
- electron positron: colliding beams
- electron positron: annihilation
- quark: charm
- quark: multiple production
- final state: (4charm)
- J/psi(3100): direct production
- quark: fragmentation
- eta/c(2980): associated production
- D*(2010): associated production
- channel cross section: branching ratio
References(17)
Figures(0)