Details

Autor(en) / Beteiligte

• Longfellow, B
• Gallant, A T
• Sargsyan, G H
• Burkey, M T
• Hirsh, T Y
• Savard, G
• Scielzo, N D
• Varriano, L
• Brodeur, M
• Burdette, D P
• Clark, J A
• Lascar, D
• Launey, K D
• Mueller, P
• Ray, D
• Sharma, K S
• Valverde, A A
• Wilson, G L
• Yan, X L

Titel

Improved Tensor Current Limit from ^{8}B β Decay Including New Recoil-Order Calculations

Ist Teil von

• Physical review letters, 2024-04, Vol.132 (14), p.142502-142502

Ort / Verlag

United States

Erscheinungsjahr

2024

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• A precision measurement of the β^{+} decay of ^{8}B was performed using the Beta-decay Paul Trap to determine the β-ν angular correlation coefficient a_{βν}. The experimental results were combined with new ab initio symmetry-adapted no-core shell-model calculations to yield the second-most precise measurement from Gamow-Teller decays, a_{βν}=-0.3345±0.0019_{stat}±0.0021_{syst}. This value agrees with the standard model value of -1/3 and improves uncertainties in ^{8}B by nearly a factor of 2. By combining results from ^{8}B and ^{8}Li, a tight limit on tensor current coupling to right-handed neutrinos was obtained. A recent global evaluation of all other precision β decay studies suggested a nonzero value for right-handed neutrino coupling in contradiction with the standard model at just above 3σ. The present results are of comparable sensitivity and do not support this finding.