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First Direct Determination of the Superallowed β-Decay QEC Value for (14)O.
A A Valverde1,2, G Bollen2,3, M Brodeur4
1National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824 USA.
Physical Review Letters
|July 22, 2015
Summary
Researchers precisely measured the (14)O superallowed Fermi beta-decay QEC value, the final of nine traditional decays. This improves understanding of fundamental physics and limits on scalar currents.
Area of Science:
- Nuclear Physics
- Particle Physics
Background:
- Superallowed Fermi beta decays provide sensitive tests of the Standard Model.
- Previous measurements of the (14)O decay were limited in precision.
- The (14)O and (10)C isotopes are crucial for constraining potential scalar currents.
Purpose of the Study:
- To perform the first direct measurement of the (14)O superallowed Fermi beta-decay QEC value.
- To improve the precision of the superallowed beta-decay QEC value and calculated statistical rate function.
- To provide a more accurate Ft value for (14)O decay.
Main Methods:
- Utilized Penning trap mass spectrometry for direct measurement.
- Measured the ground state QEC value of (14)O.
- Combined new measurements with existing data for the daughter state energy.
Main Results:
- The ground state QEC value for (14)O was determined to be 5144.364(25) keV.
- A new determination of the superallowed beta-decay QEC value, QEC(sa), was achieved with an order of magnitude improvement in precision.
- An improved Ft value of 3073.8(2.8) s was calculated.
Conclusions:
- This study provides the most precise QEC value for (14)O superallowed Fermi beta-decay.
- The enhanced precision contributes to more stringent limits on scalar currents.
- The results validate and refine fundamental tests of the Standard Model in nuclear physics.
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