A Measurement of the Michel parameters in leptonic decays of the tau

Collaboration
Dec, 1996
10 pages
Published in:
  • Phys.Rev.Lett. 78 (1997) 4686-4690
Report number:
  • CLNS-96-1429,
  • CLEO-96-15,
  • SLAC-PUB-9811
Experiments:
  • CESR-CLEO-II

Citations per year

199720032009201520210123456
Abstract: (APS)
We have measured the spectral shape Michel parameters ρ and η using leptonic decays of the τ, recorded by the CLEO II detector. Assuming e−μ universality in the vectorlike couplings, we find ρeμ=0.735±0.013±0.008 and ηeμ=−0.015±0.061±0.062, where the first error is statistical and the second systematic. We also present measurements for the parameters for e and μ final states separately.
  • electron positron: colliding beams
  • electron positron: annihilation
  • tau: electroproduction
  • tau: pair production
  • tau: leptonic decay
  • lepton: momentum spectrum
  • Michel parameter
  • model: weak interaction
  • universality: (muon electron)
  • vertex function: (W tau neutrino/tau)