发表机构
Czech Technical University in Prague; Institute of Experimental and Applied Physics, Czech Technical University in Prague（布拉格捷克技术大学; 布拉格捷克技术大学实验与应用物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
将标准模型的偶然B+L对称性提升为PQ对称性，通过单圈图实现自发质子衰变，并预测了质子衰变通道和轴子-光子耦合的可检验信号。
AI 中文摘要
我们将标准模型的偶然$B+L$对称性提升为Peccei-Quinn (PQ)对称性，同时通过辐射方式实现自发质子衰变。PQ反常扇区由矢量样夸克(VLQs)组成，提供了Kim-Shifman-Vainshtein-Zakharov型轴子解以解决强CP问题。在自发PQ破缺后，剩余一个$\mathcal{Z}_2$对称性，禁止树图级质子衰变。产生QCD反常所需的VLQs，连同在剩余$\mathcal{Z}_2$下为奇数的标量媒介子，通过有效算符$u_R u_R d_R e_R$诱导单圈质子衰变。我们研究了其紫外完备化，涉及不同的矢量样费米子和标量表示，并表明所得模型导致轴子-光子耦合的不同预言，可在太阳望远镜和晕镜实验中检验。除了质子衰变道$p \rightarrow e^+ \pi^0$，该框架还预言了末态含轴子的质子衰变$p \rightarrow e^+ \pi^0 a$，其被PQ破缺标度压低。我们还讨论了暴胀前和暴胀后宇宙学中的轴子暗物质。
英文摘要
We promote the accidental $B+L$ symmetry of the Standard Model to a Peccei-Quinn (PQ) symmetry while realizing spontaneous proton decay radiatively. The PQ anomaly sector consists of vector-like quarks (VLQs), providing a Kim-Shifman-Vainshtein-Zakharov-type axion solution to the strong CP problem. After spontaneous PQ breaking, a residual $\mathcal{Z}_2$ symmetry remains, which forbids tree-level proton decay. The VLQs required to generate the QCD anomaly, together with scalar mediators, odd under the residual $\mathcal{Z}_2$, induce one-loop proton decay through the effective operator $u_R u_R d_R e_R$. We study its ultraviolet completions, featuring distinct vector-like fermion and scalar representations, and show that the resulting models lead to distinct predictions for the axion-to-photon coupling, testable in helioscope and haloscope experiments. We investigate proton and neutron decay pheneomenology focusing on the channel $p \rightarrow e^+ π^0$. We also discuss axion dark matter in pre- and post-inflationary cosmology.
Comments17 LaTeX pages; 3 figures. Minor changes in main text, Fig.3 updated with new plot added and references added. Matches version published in PLB
DOI：10.1016/j.physletb.2026.140918
