1. Direct Measurement of the Pseudoscalar Decay Constant, fDs
- Author
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Bai, JZ, Bardon, O, Blum, I, Breakstone, A, Burnett, T, Chen, GP, Chen, HF, Chen, J, Chen, SJ, Chen, SM, Chen, Y, Chen, YB, Chen, YQ, Cheng, BS, Cowan, RF, Cui, HC, Cui, XZ, Ding, HL, Du, ZZ, Dunwoodie, W, Fan, XL, Fang, J, Fero, M, Gao, CS, Gao, ML, Gao, SQ, Gao, WX, Gratton, P, Gu, JH, Gu, SD, Gu, WX, Gu, YF, Guo, YN, Han, SW, Han, Y, Harris, FA, Hatanaka, M, He, J, He, KR, He, M, Hitlin, DG, Hu, GY, Hu, HB, Hu, T, Hu, XQ, Huang, DQ, Huang, YZ, Izen, JM, Jia, QP, Jiang, CH, Jin, Y, Jones, L, Kang, SH, Kelsey, MH, Kim, BK, Lai, YF, Lan, HB, Lang, PF, Lankford, A, Li, F, Li, J, Li, PQ, Li, Q, Li, RB, Li, W, Li, WD, Li, WG, Li, X, Li, XN, Lin, SZ, Liu, HM, Liu, JH, Liu, Q, Liu, RG, Liu, Y, Liu, ZA, Lou, XC, Lowery, B, Lu, JG, M., A, C., E, M., J, Mao, HS, Mao, ZP, Malchow, R, Mandelkern, M, Meng, XC, Ni, HL, Nie, J, Olsen, SL, Oyang, J, Paluselli, D, Pan, LJ, Panetta, J, Porter, F, Prabhakar, E, Qi, ND, Que, YK, Quigley, J, and Rong, G
- Subjects
Nuclear and Plasma Physics ,Particle and High Energy Physics ,Mathematical Physics ,Mathematical Sciences ,Physical Sciences ,Intellectual and Developmental Disabilities (IDD) ,Down Syndrome ,Brain Disorders ,Engineering ,General Physics ,Mathematical sciences ,Physical sciences - Abstract
The Beijing Spectrometer (BES) experiment has observed purely leptonic decays of the Ds meson in the reaction e+e-→Ds+Ds- at a c.m. energy of 4.03 GeV. Three events are observed in which one Ds decays hadronically to φπ, K̄*0K, or K̄0K, and the other decays leptonically to μνμ or τντ. With the assumption of μ-τ universality, values of the branching fraction, B(Ds→μνμ)=(1.5-0.6-0.2+1.3+0.3)%, and the Ds pseudoscalar decay constant, fDs=(4.3-1.3-0.4+1.5+0.4)×102 MeV, are obtained. © 1995 The American Physical Society.
- Published
- 1995