The Beta Decay Asymmetry Parameter of ARGON-35.
Abstract
The beta decay asymmetry parameter for ^{35}Ar --> ^{35}Cl + e ^+ + v_{rm e} has been remeasured in order to resolve a long standing puzzle. Previous asymmetry measurements, when combined with the comparative half-life, yield a value for the vector coupling constant, G_{ rm v}, that is in serious disagreement with the accepted value. We produced polarized ^{35}Ar by a (p,n) reaction on ^{35}Cl using the polarized proton beam provided by Lawrence Berkeley Laboratory's 88-Inch Cyclotron. The polarization of the ^ {35}Ar was determined by measuring the asymmetry of the positrons produced in ^ {35}Ar decay to the first excited state in ^{35}Cl (branching ratio = 1.3%) in coincidence with a 1219.4 keV gamma ray. Our result, A_{rm o} = 0.49 +/- 0.10, combined with the comparative half-life yields a value for G_ {rm v} in agreement with the accepted value.
- Publication:
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Ph.D. Thesis
- Pub Date:
- September 1987
- Bibcode:
- 1987PhDT.......106G
- Keywords:
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- Physics: Nuclear