National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA.
Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA.
Phys Rev Lett. 2016 Jan 8;116(1):012501. doi: 10.1103/PhysRevLett.116.012501. Epub 2016 Jan 6.
We report the determination of the Q(EC) value of the mirror transition of (11)C by measuring the atomic masses of (11)C and (11)B using Penning trap mass spectrometry. More than an order of magnitude improvement in precision is achieved as compared to the 2012 Atomic Mass Evaluation (Ame2012) [Chin. Phys. C 36, 1603 (2012)]. This leads to a factor of 3 improvement in the calculated Ft value. Using the new value, Q(EC)=1981.690(61) keV, the uncertainty on Ft is no longer dominated by the uncertainty on the Q(EC) value. Based on this measurement, we provide an updated estimate of the Gamow-Teller to Fermi mixing ratio and standard model values of the correlation coefficients.
我们通过彭宁阱质谱法测量 (11)C 和 (11)B 的原子质量，从而确定了 (11)C 镜像跃迁的 Q(EC) 值。与 2012 年原子质量评估 (Ame2012) [Chin. Phys. C 36, 1603 (2012)] 相比，精度提高了一个数量级。这导致 Ft 值的计算提高了 3 倍。使用新值 Q(EC)=1981.690(61)keV，Ft 的不确定度不再由 Q(EC) 值的不确定度主导。基于此次测量，我们提供了对 Gamow-Teller 到费米混合比以及关联系数的标准模型值的更新估计。
