1. First measurement of the branching fraction of the decay ψ(2S)→τ+τ-
- Author
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Bai, JZ, Ban, Y, Bian, JG, Blum, I, Chen, AD, Chen, HF, Chen, HS, Chen, J, Chen, JC, Chen, XD, Chen, Y, Chen, YB, Cheng, BS, Chi, SP, Chu, YP, Choi, JB, Cui, XZ, Dai, YS, Dong, LY, Du, ZZ, Dunwoodie, W, Fu, HY, Fu, LP, Gao, CS, Gratton, P, Gu, SD, Gu, YF, Guo, YN, Guo, ZJ, Han, SW, Han, Y, Harris, FA, He, J, He, JT, He, KL, He, M, He, X, Hong, T, Heng, YK, Hitlin, DG, Hu, GY, Hu, HM, Hu, QH, Hu, T, Huang, GS, Huang, XP, Huang, YZ, Izen, JM, Ji, XB, Jiang, CH, Jin, Y, Jones, BD, Kang, JS, Ke, ZJ, Kelsey, MH, Kim, BK, Kim, HJ, Kim, SK, Kim, TY, Kong, D, Lai, YF, Lankford, A, Li, D, Li, HB, Li, HH, Li, J, Li, JC, Li, PQ, Li, QJ, Li, RY, Li, W, Li, WG, Li, XN, Li, XQ, Liu, B, Liu, F, Liu, Feng, Liu, HM, Liu, J, Liu, JP, Liu, TR, Liu, RG, Liu, Y, Liu, ZX, Lou, XC, Lowery, B, Lu, GR, Lu, F, Lu, JG, Lu, ZJ, Luo, XL, C., E, M., J, Malchow, R, Mao, HS, Mao, ZP, Meng, XC, Mo, XH, Nie, J, and Nie, ZD
- Subjects
Nuclear and Plasma Physics ,Particle and High Energy Physics ,Physical Sciences ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Quantum Physics ,Nuclear & Particles Physics ,Mathematical physics ,Astronomical sciences ,Particle and high energy physics - Abstract
The branching fraction of the ψ(2S) decay into τ+τ - has been measured for the first time using the BES detector at the Beijing Electron-Positron Collider. The result is Bττ=(2.710. 43±0.55)× 10-3, where the first error is statistical and the second is systematic. This value, along with those for the branching fractions into e+e- and μ+ μ- of this resonance, satisfy well the relation predicted by the sequential lepton hypothesis. Combining all these values with the leptonic width of the resonance, the total width of the ψ(25) is determined to be (252±37) keV. ©2002 The American Physical Society.
- Published
- 2002