A Measurement of the Michel Parameters in Leptonic Decays of the Tau
Abstract
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.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 1997
- DOI:
- 10.1103/PhysRevLett.78.4686
- Bibcode:
- 1997PhRvL..78.4686A