학술논문

First measurement of the branching fraction of the decay ψ(2S)→τ+τ-
Document Type
article
Source
Physical Review D. 65(5)
Subject
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
Language
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.