粲重子素
Charmed Baryonium
摘要：
我们重新分析了已发表的Y（4630）--> Lambda_c Lambdabar_c和Y（4660）--> psi（2S）pi pi的观测数据，发现这两个观测结果可能是由于同一个态Y_B，M_{Y_B} = 4660.7 ± 8.7 MeV和Gamma_{Y_B} = 61 ± 23 MeV。在此假设下，再分析e+e- -> J/psi pi pi gamma_ISR谱，我们提取B（Y_B --> Lambda_c）/ B（Y_B --> psi（2S）pi pi）= 25 ± 7，B（Y_B --> J/psi pi pi）/ B（Y_B --> psi（2S）pi pi）<0. 46 @ 90% C.L.，B（Y（4350）--> J/psi pi pi）/ B（Y（4350）--> psi（2S）pi pi）< 3.4 x 10^-3@90% C. L. B（Y_B --> psi（2S）σ）/ B（Y_B --> psi（2S）f_0）=2.0 ± 0.3。这些结论有力地支持了Y_B是首次观测到由四个夸克组成的粲重子的假设。从质谱和衰变性质的分析表明，Y（4350）和Y_B分别与L=1态的基态和第一径向激发相一致。
英文摘要：
We re-analyze the published data on the Y(4630) --> Lambda_c Lambdabar_c and the Y(4660) --> psi(2S) pi pi with a consistent Ansatz and we find that the two observations are likely to be due to the same state Y_B with M_{Y_B} = 4660.7 +- 8.7 MeV and Gamma_{Y_B} = 61 +- 23 MeV. Under this hypothesis and reanalizing also the e+e- --> J/psi pi pi gamma_ISR spectrum we extract B(Y_B --> Lambda_c Lambdabar_c) / B(Y_B --> psi(2S) pi pi) = 25 +- 7, B(Y_B --> J/psi pi pi) / B(Y_B --> psi(2S) pi pi) < 0.46 @ 90% C.L., B(Y(4350) --> J/psi pi pi) / B(Y(4350) --> psi(2S) pi pi) < 3.4 x 10^-3 @ 90% C.L. and B(Y_B --> psi(2S) sigma) / B (Y_B --> psi(2S) f_0)=2.0 +- 0.3. These conclusions strongly support the hypothesis of Y_B being the first observation of a charmed baryonium constituted by four quarks. From the analysis of the mass spectrum and the decay properties we show that Y(4350) and Y_B are respectively consistent with the ground state and first radial excitation of the L=1 state.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
