发表机构
University of California, Berkeley; University of California, San Diego; Harvard University（加州大学伯克利分校; 加州大学圣迭戈分校; 哈佛大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文推导出KK引力子间一般衰变率，发现其被$(q/m_n)^2$抑制，并论证该结果的普适性，对级联暗物质模型及暗维度模型的排除有重要意义。
AI 中文摘要
我们得到了Kaluza-Klein（KK）引力子之间的一般衰变率，解决了文献中关于这些衰变的一个歧义。该振幅不仅取决于衰变粒子的质量$m_n$，还取决于衰变产物在母粒子静止系中的动量$q$，并且相对于文献中常用的表达式被抑制了$(q/m_n)^2$因子。相空间给出了一个一般的$q^5$依赖的衰变率，这一结果在Randall-Sundrum模型中先前已得到。我们确定了产生这一结果的抵消是无质量5维引力子的一个结果，并论证了其普适性，即使存在标量诱导的KK破坏，通过将非最小耦合的标量场吸收进翘曲因子也能保持。这对级联暗物质模型的潜力有重要意义，并可用于排除现有的暗维度模型，因为原本为规避约束所需的快速级联被严重抑制。该振幅通过一个显式计算确立，该计算考虑了场和膜的反作用，并广泛适用于标量场与引力之间的非最小微分同胚不变二阶导数耦合。
英文摘要
We obtain a general decay rate between Kaluza-Klein (KK) gravitons, resolving an ambiguity in the literature concerning these decays. The amplitude is determined not only by the mass $m_n$ of the decaying particle, but also by the momentum $q$ of the decay products in the parent's rest frame, and is suppressed relative to the expression commonly used in the literature by $(q/m_n)^2$. Phase space gives a general $q^5$-dependent decay rate obtained earlier in Randall-Sundrum models. We identify the cancellation that gives this result as a consequence of the massless 5D graviton, and argue for its universality even with scalar-induced KK violation by absorbing non-minimally coupled scalar fields into the warp-factor. This has significant implications for the potential for cascading dark matter models, and can be used to rule out existing Dark Dimension models, because the rapid cascade that was needed to evade constraints is severely suppressed. The amplitude is established by an explicit calculation that accounts for the backreaction of fields and branes and applies broadly to non-minimal diffeomorphism invariant two-derivative couplings between scalar fields and gravity.
Comments11 pages
