Search for C violation in the decay ? ? p0e+e- with WASA-at-COSY
Search for C violation in the decay ? ? p0e+e- with WASA-at-COSY
复制标题
在衰变中寻找 C 违规？
DOI：
10.1016/j.physletb.2018.07.017
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发表时间：
2018
影响因子：
4.4
通讯作者：
Adlarson P
中科院分区：
文献类型：
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作者：
Adlarson P
根据标准模型，强相互作用和电磁相互作用必须保持C宇称。这个概念特别限制了介子的衰变模式，例如，高度抑制了η→ π 0 e +e−。然而，相对分支比的相应测量可以追溯到上个世纪的70年代，并且它们的灵敏度仅限于标准模型预测值以上的许多数量级。通过单光子中间态η→ π0γ π的过程η→ π 0 e +e−将违反C宇称守恒，而根据理论计算，作为物理背景的双光子过程的预期分支比不大于10− 8 [1-3]。这一过程的现代模型包括一个假设的大质量暗U玻色子[4-6]与虚光子的耦合，其中相应的相互作用强度与2 q2/
According to the standard model, strong and electromagnetic interactions have to conserve C parity. This concept particularly restricts the decay modes of mesons and, as an instance, highly suppresses η→ π0e+e−. However, corresponding measurements of the relative branching ratio date back to the seventies of the last century and their sensitivity is limited to many orders of magnitudes above the standard model predictions. The process η→ π0e+e− via the single-photon intermediate state η→ π0γ∗ would violate C parity conservation whereas a two-photon process as a physical background has an expected branching ratio not larger than 10− 8 according to theoretical calculations [1–3]. A modern model for this process includes the coupling of a hypothetical massive dark U boson [4–6] to the virtual photon where the corresponding interaction strength scales with∼ ϵ2q2/