Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China.
In a sample of 58 million J/psi events collected with the BES II detector, the process J/psi --> gamman(c) is observed in five different decay channels: gammaK(+)K(-)pi(+)pi(-), gammapi(+)pi(-)pi(+)pi(-). gammaK(+/-)K(S)(0)pi(-/+) (with K-S(0) --> pi(+)pi(-)), gammaphiphi (with phi -->K+K-) and gammap (p) over bar. From a combined fit of all five channels, we determine the mass and full-width of the n(c) to be m(nc) = 2977.5 +/- 1.0 (stat.) +/- 1.2 (syst.) MeV/c(2) and Gamma(nc) = 17.0 +/- 3.7 (stat.) +/- 7.4 (syst.) MeV/c(2). (C) 2003 Elsevier Science B.V. All rights reserved.