AI 中文总结
本文通过破缺SU(3)味对称性分析弱辐射超子衰变，拟合得χ²/自由度=0.98，支持α_γ(Ξ⁻→Σ⁻γ)取较大负值，其与实验值差约1.3σ，未来测量可检验该预测。
AI 中文摘要
我们对自旋1/2超子的弱辐射衰变开展了破缺SU(3)味对称性分析，纳入了流流项、电磁企鹅项以及电荷插入和质量插入效应。六个独立的约化振幅可描述所有衰变道，而宇称守恒与宇称破缺形状因子间的最小关系将自由参数缩减为八个。对十个现有可观测量的全局拟合给出χ²/自由度=0.98，且能容纳Σ⁺→pγ中较大的负不对称性。所得非零有效形状因子g_b8为宇称破缺振幅提供了可能的味对称性实现，同时与哈拉定理兼容——该定理在严格对称性极限下约束流流项贡献。我们的分析支持α_γ(Ξ⁻→Σ⁻γ)取较大负值，该值与当前实验结果相差约1.3σ，未来对该可观测量的精确测量将为这一预测提供决定性检验。
英文摘要
We present a broken $SU(3)$ flavor analysis of weak radiative decays of spin-1/2 hyperons, incorporating current-current and electromagnetic-penguin contributions as well as charge- and mass-insertion effects. Six independent reduced amplitudes describe all decay channels, while a minimal relation between the parity-conserving and parity-violating form factors reduces to eight free parameters. A global fit to the ten available observables yields $χ^2/\mathrm{d.o.f.}=0.98$ and accommodates the large negative asymmetry in $Σ^+\to pγ$. The resulting nonzero effective form factor $g_{b_8}$ provides a possible flavor-symmetry realization of the parity-violating amplitude while remaining compatible with Hara's theorem, which constrains the current-current contribution in the exact symmetry limit. Our analysis favors a sizable negative value of $α_γ(Ξ^- \to Σ^- γ)$, which differs from the current experimental result by approximately $1.3σ$. Future precision measurements of this observable will provide a decisive test of this prediction.
Comments6 pages, 3 tables
