Measurement of branching ratios
198622 pages
Published in:
- Phys.Rev.D 35 (1987) 1553
Report number:
- JHU-HEP-86-104
Experiments:
- SLAC-PEP-004
Citations per year
Abstract: (APS)
We have measured the branching ratios for several τ decay modes. We use e+e−→τ+τ− events accumulated with the TPC/Two-Gamma facility at the SLAC e+e− storage ring PEP. The data correspond to an integrated luminosity of 77 pb−1 at a center-of-mass energy of 29 GeV. The one- and three-charged-particle inclusive branching ratios of the τ decay are measured to be B1=(84.7±1.0)% and B3=(15.1±1.0)%, where B1+B3 is constrained to be 99.85%. The branching ratios of the two leptonic decay modes are B(τ−→e− ν¯eντ)=(18.4±1.6)% and B(τ−→μ− ν¯μντ)=(17.7±1.4)%. If we then assume lepton universality, we obtain B(τ−→e− ν¯eντ)=(18.3±0.9)% and B(τ−→μ− ν¯μντ)=(17.8±0.9)%. We measure the Cabibbo-allowed semihadronic decay mode B(τ−→π−+neutral particles)=(47.0±1.5)%, and the Cabibbo-suppressed τ decay mode B(τ−→K−+neutral particles)=(1.6±0.4)%. By looking for associated photons, we find B(τ−→K−π0+neutral particles) to be (1.2±0.6)%. Using the channel K*−→KSOπ+π−, we find B(τ−→K*−(892)+neutral particles)=(1.4±0.9)%. The quoted errors are the combined statistical and systematic errors.- ELECTRON POSITRON: COLLIDING BEAMS
- COLLIDING BEAMS: ELECTRON POSITRON
- ELECTRON POSITRON: ANNIHILATION
- ANNIHILATION: ELECTRON POSITRON
- TAU: ELECTROPRODUCTION
- ELECTROPRODUCTION: TAU
- TAU: PAIR PRODUCTION
- PAIR PRODUCTION: TAU
- TAU: LEPTONIC DECAY
- LEPTONIC DECAY: TAU
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