论文标题
Grossman-Nir绑定的三个例外
Three Exceptions to the Grossman-Nir Bound
论文作者
论文摘要
我们表明，Grossman-nir（Gn）绑定，$ \ text {br}（k_l \ toπ^0ν\barν）\ leq 4.3 \，\ text {br}（k^+\toπ^+\toπ^+t ofπ^+b bar）$，可以在带有新的物理学的情况下违反侵蚀味道。我们构建了三个样本模型，其中可以通过数量级违反GN结合，同时满足所有其他实验界限。在三个模型中，增强的分支比$ \ text {br}（k_l \toπ^0+{\ rm inv}）$归因于$ k_l \toπ^0 ϕ_1 $，$ k_l \toπ^0DACTON_1 （ψ_1）$是逃脱检测器的轻标量（费米）。在三个模型中，$ \ text {br}（k^+\toπ^++ {\ rm inv}）$保持非常接近SM值，而$ \ text {br}（k_l \ to -π^0+{\ rm rm {\ rm inv}）$可以使当前的koto限制饱和。除了最终状态（可能是暗物质）中的看不见的颗粒外，模型还需要GEV尺度周围的其他光介体。
We show that the Grossman-Nir (GN) bound, $\text{Br}(K_L\to π^0ν\barν)\leq 4.3 \, \text{Br}(K^+\to π^+ν\barν)$, can be violated in the presence of light new physics with flavor violating couplings. We construct three sample models in which the GN bound can be violated by orders of magnitude, while satisfying all other experimental bounds. In the three models the enhanced branching ratio $\text{Br}(K_L\to π^0+{\rm inv})$ is due to $K_L\to π^0ϕ_1$, $K_L\to π^0ϕ_1ϕ_1$, $K_L\to π^0ψ_1\bar ψ_1$ transitions, respectively, where $ϕ_1 (ψ_1)$ is a light scalar (fermion) that escapes the detector. In the three models $\text{Br}(K^+\to π^++{\rm inv})$ remains very close to the SM value, while $\text{Br}(K_L\to π^0+{\rm inv})$ can saturate the present KOTO bound. Besides invisible particles in the final state (which may account for dark matter) the models require additional light mediators around the GeV-scale.
