Study of heavy-lepton production in e/sup +/e/sup -/ annihilation

Journal Article · Thu Jul 01 00:00:00 EDT 1976 · Phys. Rev., D; (United States)

DOI:https://doi.org/10.1103/PhysRevD.14.59· OSTI ID:7272555

Fujikawa, K; Kawamoto, N

We present a numerical study of the collinearity-angle distribution for e and ..mu.. in the process e anti e ..-->.. L anti L and the subsequent decay L ..-->.. ..nu../sub L/ + l + anti ..nu../sub l/, l = ..mu.. or e. V + A as well as V - A couplings for the heavy lepton are considered together with a nonvanishing mass for ..nu../sub L/. A V + A current with a massless or massive neutrino or a V - A current with a massive neutrino gives rise to more e..mu.. events at smaller collinearity angles than the standard V - A sequential lepton with a massless neutrino. A smaller heavy-lepton mass and larger experimental energy cutoff also give rise to smaller collinearity angles. It appears to be possible to distinguish these dynamical and kinematical effects based on experimental data with better statistics than available at present. We note that the experimental determination of the leptonic branching ratio is sensitive to the coupling scheme and the neutrino mass. We present an expected collinearity-angle distribution for l..pi.. events (l = ..mu.. or e), which may be conveniently used to fix the mass of ..nu../sub L/. The effects of the possible existence of heavy leptons on the decreasing charged energy fraction in e anti e annihilation are also briefly discussed on the basis of recent data. A heavy lepton with mass approx. 1.8 GeV can account for the decrease up to W approx. 6 GeV. To explain the further decrease in the charged energy fraction entirely in terms of heavy leptons, however, another heavy lepton with mass approx. 2.8 GeV accompanied by a massive neutrino is required. We comment on the effects of such heavier leptons on the e..mu.. cross section. (AIP)

• Research Organization: Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
• OSTI ID: 7272555
• Journal Information: Phys. Rev., D; (United States), Vol. 14:1
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
HEAVY LEPTONS
V-A THEORY ANNIHILATION
ELECTRON-POSITRON INTERACTIONS
ANNIHILATION
ANGULAR DISTRIBUTION
REACTION KINETICS
V-A THEORY
ANTINEUTRINOS
ELECTRONS
MUONS
NEUTRINOS
POSITRONS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
BASIC INTERACTIONS
DECAY
DISTRIBUTION
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
FERMIONS
INTERACTIONS
KINETICS
LEPTON-LEPTON INTERACTIONS
LEPTONS
MASSLESS PARTICLES
PARTICLE DECAY
PARTICLE INTERACTIONS
POSTULATED PARTICLES
WEAK INTERACTIONS
WEAK PARTICLE DECAY
645203* - High Energy Physics- Particle Interactions & Properties-Theoretical- Weak Interactions & Properties
645202 - High Energy Physics- Particle Interactions & Properties-Theoretical- Electromagnetic Interactions & Properties