Search for right-handed currents by means of muon spin rotation

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5227046

Stoker, D P

A muon spin rotation (..mu..SR) technique has been used to place limits on right-handed weak currents in ..mu../sup +/ decay. A beam of almost 100% polarized surface muons obtained from the TRIUMF M13 beamline was stopped in essentially non-depolarizing >99.99% pure metal foils. The ..mu../sup +/ spins were precessed by 70-G or 110-G transverse fields. Decay e/sup +/ emitted within 225 mrad of the beam direction and with momenta above 46 MeV/c were momentum-analyzed to 0.2%. Comparison of the ..mu..SR signal amplitude with that expected for (V-A) decay yields an endpoint asymmetry XiP/sub ..mu../delta/rho > 0.9951 with 90% confidence. In the context of manifest left-right symmetric models with massless neutrinos the results imply the 90% confidence limits M(W/sub 2/) > 381 GeV/c/sup 2/ and -0.057 < zeta < 0.044, where W/sub 2/ is a predominantly right-handed gauge boson and zeta is the left-right mixing angle. Limits on M(W/sub 2/) for M(nu/sub ..mu..R/) does not equal 0 are also presented. The endpoint asymmetry is used to deduce limits on the nu/sub ..mu..L/ mass and helicity in ..pi../sup +/ decay, non-(V-A) couplings in helicity projection form, and the mass scale of composite leptons.

• Research Organization: California Univ., Berkeley (USA)
• OSTI ID: 5227046
• Country of Publication: United States
• Language: English

Related Subjects

645102* -- High Energy Physics-- Particle Interactions &amp; Properties-Experimental-- Weak Interactions &amp; Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCELERATORS
ALGEBRAIC CURRENTS
ANGULAR MOMENTUM
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
CURRENTS
CYCLIC ACCELERATORS
CYCLOTRONS
DATA
DECAY
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FERMIONS
INFORMATION
ISOCHRONOUS CYCLOTRONS
LEPTONS
LINEAR MOMENTUM
MASS
MASSLESS PARTICLES
MUONS
MUONS PLUS
NEUTRAL CURRENTS
NEUTRINOS
NUMERICAL DATA
PARTICLE DECAY
PARTICLE PROPERTIES
POSITRONS
REST MASS
SPIN
TRIUMF CYCLOTRON
WEAK NEUTRAL CURRENTS
WEAK PARTICLE DECAY