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High-precision half-life measurement for the superallowed β+ emitter ²⁶Al(m)
P Finlay1, S Ettenauer, G C Ball
1Department of Physics, University of Guelph, Guelph, Ontario, Canada N1G 2W1. pfinlay@uoguelph.ca
Physical Review Letters
|March 17, 2011
Summary
A precise measurement of the half-life for the superallowed beta-plus emitter 26Al(m) was achieved. This new data refines tests of fundamental physics and the determination of a key quark mixing matrix element.
Area of Science:
- Nuclear Physics
- Particle Physics
Background:
- Superallowed beta decays provide sensitive probes of the weak interaction.
- Precise measurements are crucial for testing the Conserved Vector Current (CVC) hypothesis.
- Previous half-life measurements for 26Al(m) limited the precision of derived parameters.
Purpose of the Study:
- To perform a high-precision half-life measurement of the 26Al(m) isotope.
- To improve the accuracy of the ft value for 26Al(m) superallowed beta decay.
- To enhance tests of the CVC hypothesis and the determination of the V(ud) quark mixing matrix element.
Main Methods:
- Utilized the TRIUMF-ISAC radioactive ion beam facility for precise measurements.
- Employed advanced techniques for high-precision half-life determination of 26Al(m).
Main Results:
- Achieved a half-life measurement of T 1/2 = 6346.54 ± 0.46(stat) ± 0.60 (syst) ms for 26Al(m).
- The determined half-life is 2.5 times more precise than the previous world average.
- The corrected Ft value for 26Al(m) is 3073.0(12) s, setting a new benchmark.
Conclusions:
- The high-precision 26Al(m) half-life measurement significantly improves upon previous results.
- The refined Ft value provides a stringent test of the CVC hypothesis.
- This study enhances the precision of the V(ud) element determination within the CKM matrix.
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