Journal article
Observation of double c(c)over-bar production in e e- annihilation at √s≈10.6 GeV -: art. no. 142001
K Abe, K Abe, R Abe, T Abe, I Adachi, BS Ahn, H Aihara, M Akatsu, Y Asano, T Aso, V Aulchenko, T Aushev, AM Bakich, Y Ban, E Banas, W Bartel, A Bay, PK Behera, A Bondar, A Bozek Show all
PHYSICAL REVIEW LETTERS | AMER PHYSICAL SOC | Published : 2002
Abstract
We report the observation of prompt J/psi via double cc; production from the e+e- continuum. In this process one cc; pair fragments into a J/psi meson while the remaining pair either produces a charmonium state or fragments into open charm. Both cases have been experimentally observed. We find cross sections of sigma[e+e- -->J/psieta(c)(gamma)]xB(eta(c)-->>or=4 charged)=(0.033(+0.007)(-0.006)+/-0.009) pb and sigma(e+e- -->J/psiD(*+)X)=(0.53(+0.19)(-0.15)+/-0.14) pb and infer sigma(e+e- -->J/psicc;)/sigma(e+e- -->J/psiX)=0.59(+0.15)(-0.13)+/-0.12. These results are obtained from a 46.2 fb(-1) data sample collected near the Upsilon(4S) resonance, with the Belle detector at the KEKB collider.