Nature of the tau-. nu. /sub tau/-W coupling

Journal Article · Mon Mar 19 04:00:00 EST 1979 · Phys. Rev. Lett.; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.42.749· OSTI ID:6079216

Bacino, W; Ferguson, T; Nodulman, L; Slater, W E; Ticho, H K; Diamant-Berger, A; Donaldson, G; Duro, M; Hall, A; Irwin, G; Kirkby, J; Merritt, F; Wojcicki, S; Burns, R; Condon, P; Cowell, P; Kirz, J

The electron momentum spectrum observed in the decay tau ..-->.. ..nu../sub tau/e..nu../sub e/ is in good agreement with the V--A hypothesis. The measured value of the Michel parameter, rho = 0.72 +- 0.15, excludes a V + A current and disfavors pure V or A currents. The spectrum allows us to set an upper limit of 250 MeV/c/sup 2/ (95% confidence level) for the tau neutrino mass. Finally, by measuring the tau-lifetime upper limit of 2.3 x 10/sup -12/ sec (95% confidence level), we show that the square of the coupling constant at the tau-..nu../sub tau/-W vertex is at least 12% of full weak strength.

• Research Organization: Physics Department, University of California, Los Angeles, California 90024
• OSTI ID: 6079216
• Journal Information: Phys. Rev. Lett.; (United States), Journal Name: Phys. Rev. Lett.; (United States) Vol. 42:12; ISSN PRLTA
• Country of Publication: United States
• Language: English

Related Subjects

645102* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Weak Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BASIC INTERACTIONS
BOSONS
COUPLING CONSTANTS
DECAY
ELECTRON NEUTRINOS
ELECTRON SPECTRA
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
HEAVY LEPTONS
INTERACTIONS
INTERMEDIATE BOSONS
INTERMEDIATE VECTOR BOSONS
LEPTONIC DECAY
LEPTONS
LIFETIME
LIMITING VALUES
LINEAR MOMENTUM
MASS
MASSLESS PARTICLES
NEUTRINOS
PARTICLE DECAY
POSTULATED PARTICLES
SPACE-TIME
SPECTRA
TAU NEUTRINOS
TAU PARTICLES
V-A THEORY
WEAK INTERACTIONS
WEAK PARTICLE DECAY