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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
Tenth-order QED contribution to the electron g-2 and an improved value of the fine structure constant
Tatsumi Aoyama1, Masashi Hayakawa, Toichiro Kinoshita
1Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University, Nagoya, 464-8602, Japan.
Abstract:
This letter presents the complete QED contribution to the electron g-2 up to the tenth order. With the help of the automatic code generator, we evaluate all 12,672 diagrams of the tenth-order diagrams and obtain 9.16 (58)(α/π)(5). We also improve the eighth-order contribution obtaining -1.9097 (20)(α/π)(4), which includes the mass-dependent contributions. These results lead to a(e)(theory)=1,159,652,181.78(77)×10(-12). The improved value of the fine-structure constant α(-1)=137.035999173 (35) [0.25 ppb] is also derived from the theory and measurement of a(e).
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