AI 中文总结
该研究探索翘曲额外维度的强度前沿信号，构建含GeV级膜的光子门户模型，提出重KK引力子产生、级联及宏观电磁衰变的特征，讨论低标度翘曲场景的相关约束。
AI 中文摘要
翘曲额外维度能否首先出现在强度前沿，而非对撞机上的TeV级共振态？我们在扩展翘曲模型中探索这一可能性，该模型中引力传播至深红外区域，翘曲标度Λ_IR~O(MeV)，产生密集排列的卡鲁扎-克莱因（KK）引力子塔。我们构建了一个基准光子门户实现方案，其中可见矢量区到达中间GeV级膜，而希格斯区仍与更高翘曲标度相关联。由此产生的引力子-光子耦合由额外维度中的波函数重叠控制，因此产生率并不像传统轻中介简化模型那样仅由独立的质量和耦合决定。相反，在束流 dump 环境中的GeV级光子可优先产生更重的KK引力子，其分布探测中间膜，之后激发态在塔内级联下降。若末态模式衰变为类似伸缩子的态在运动学上关闭，最轻的可及KK引力子可以是长寿命的，并可见地衰变为一对光子。这产生了独特的强度前沿特征：重模式产生、塔内簇射和宏观电磁衰变。我们介绍了模型要素，推导了相关的重叠控制耦合，表征了通用的产生和衰变现象学，并讨论了这类低标度翘曲场景的理论和精度约束。
英文摘要
Can warped extra dimensions first appear at the intensity frontier rather than as TeV-scale resonances at colliders? We explore this possibility in extended warped models in which gravity propagates to a deep infrared region with warped scale $Λ_{\rm IR}\sim \mathcal{O}({\rm MeV})$, producing a densely spaced Kaluza-Klein (KK) graviton tower. We develop a benchmark photon-portal realization in which a visible vector sector reaches an intermediate GeV-scale brane, while the Higgs sector remains associated with a higher warped scale. The resulting graviton-photon couplings are controlled by wave-function overlap in the extra dimension, so the production rate is not governed simply by an independent mass and coupling as in conventional light-mediator simplified models. Instead, GeV-scale photons in beam-dump environments can preferentially produce heavier KK gravitons whose profiles probe the intermediate brane, after which the excited modes cascade down the tower. If decays into radion-like states are kinematically closed for the terminal mode, the lightest accessible KK graviton can be long-lived and decay visibly into a pair of photons. This leads to a distinctive intensity-frontier signature: heavy-mode production, intratower showering, and macroscopic electromagnetic decays. We present the model ingredients, derive the relevant overlap-controlled couplings, characterize the generic production and decay phenomenology, and discuss the theoretical and precision constraints on this class of low-scale warped scenarios.
Comments18 pages, 4 figures
