Bai JZ, Ban Y, Bian JG, Cai X, Chang JF, Chen HF, Chen HS, Chen J, Chen J, Chen JC, Chen YB, Chi SP, Chu YP, Cui XZ, Dai YM, Dai YS, Dong LY, Du SX, Du ZZ, Dunwoodie W, Fang J, Fang SS, Fu CD, Fu HY, Fu LP, Gao CS, Gao ML, Gao YN, Gong MY, Gong WX, Gu SD, Guo YN, Guo YQ, Guo ZJ, Han SW, Harris FA, He J, He KL, He M, He X, Heng YK, Hong T, Hu HM, Hu T, Huang GS, Huang L, Huang XP, Izen JM, Ji XB, Jiang CH, Jiang XS, Jin DP, Jin S, Jin Y, Jones BD, Ke ZJ, Kong D, Lai YF, Li F, Li G, Li HH, Li J, Li JC, Li K, Li QJ, Li RB, Li RY, Li W, Li WG, Li XQ, Li XS, Liu CF, Liu CX, Liu F, Liu F, Liu HM, Liu JB, Liu JP, Liu RG, Liu Y, Liu ZA, Liu ZX, Lou XC, Lu GR, Lu F, Lu HJ, Lu JG, Lu ZJ, Luo XL, Ma EC, Ma FC, Ma JM, Malchow R, Mao ZP, Meng XC, Mo XH, Nie J, Nie ZD, Olsen SL, Paluselli D, Peng HP, Qi ND, Qian CD, Qiu JF, Rong G, Shen DL, Shen H, Shen XY, Sheng HY, Shi F, Song LW, Sun HS, Sun SS, Sun YZ, Sun ZJ, Tang SQ, Tang X, Tian D, Tian YR, Toki W, Tong GL, Varner GS, Wang J, Wang JZ, Wang L, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WF, Wang YF, Wang Z, Wang Z, Wang Z, Wang ZY, Wei CL, Wu N, Xia XM, Xie XX, Xu GF, Xu Y, Xue ST, Yan ML, Yan WB, Yang GA, Yang HX, Yang J, Yang SD, Ye MH, Ye YX, Ying J, Yu CS, Yu GW, Yuan CZ, Yuan JM, Yuan Y, Yue Q, Zang SL, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HY, Zhang J, Zhang JM, Zhang JW, Zhang LS, Zhang QJ, Zhang SQ, Zhang XY, Zhang YJ, Zhang Y, Zhang YY, Zhang ZP, Zhao DX, Zhao J, Zhao JW, Zhao PP, Zhao WR, Zhao YB, Zhao ZG, Zheng JP, Zheng LS, Zheng ZP, Zhong XC, Zhou BQ, Zhou GM, Zhou L, Zhou NF, Zhu KJ, Zhu QM, Zhu Y, Zhu YC, Zhu YS, Zhu ZA, Zhuang BA, Zou BS. Observation of a near-threshold enhancement in the pp mass spectrum from radiative J/psi-->gammapp decays.
PHYSICAL REVIEW LETTERS 2003;
91:022001. [PMID:
12906471 DOI:
10.1103/physrevlett.91.022001]
[Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2003] [Indexed: 05/24/2023]
Abstract
We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.
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