发表机构
Institute of Physics; Homi Bhabha National Institute, BARC Training School Complex; Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3（印度物理研究所; 霍米·巴巴国立学院，BARC培训学院; 法国格勒诺布尔阿尔卑斯大学亚原子物理与宇宙学实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究扩展U(1)_{L_μ-L_τ}模型引入两个标量场，产生非弹性暗物质散射场景，以解释LUX-ZEPLIN观测到的248 keV过量事件，并评估模型参数敏感性及未来探测前景。
AI 中文摘要
LUX-ZEPLIN（LZ）实验最近观测到的能量为248±23（统计）±23（系统）keV的暗物质（DM）核反冲事件，倾向于非弹性散射解释，这推动了各种旨在解释该excess的超出标准模型（BSM）的场景的提出。特别地，这为探测自然容纳非弹性DM散射的模型提供了机会。在本研究中，我们通过扩展U(1)_{L_{\text{μ}}-L_{\text{τ}}}模型来探索这种可能性，引入两个复标量场Φ和S，它们在U(1)_{L_{\text{μ}}-L_{\text{τ}}}规范对称性下分别带有-1和+2的电荷。这些电荷分配允许两个标量场之间的三重线性相互作用，这对于产生DM质量分裂至关重要。在U(1)_{L_{\text{μ}}-L_{\text{τ}}}对称性自发破缺后，S获得真空期望值并为BSM规范玻色子Z_{μτ}产生质量，Φ的实部和虚部获得质量分裂，这自然产生了能够容纳LZ excess的非弹性DM散射场景。我们基于似然评估了模型参数对观测事件的敏感性，同时一致考虑了其他相关的现象学约束，最后讨论了在未来实验中探测可行参数空间的前景。
英文摘要
The recently observed dark matter (DM) nuclear recoil event at an energy of $248 \pm 23\,(\text{stat.}) \pm 23\,(\text{syst.})\,\text{keV}$ at the LUX-ZEPLIN (LZ) experiment, favoring an inelastic scattering interpretation, has motivated various beyond the Standard Model (BSM) scenarios aimed at explaining the observed excess. In particular, this provides an opportunity to probe models that naturally accommodate inelastic DM scattering. In this work, we explore one such possibility by extending the $\rm U(1)_{L_μ-L_τ}$ model with two complex scalar fields, $Φ$ and $S$, carrying charges $-1$ and $+2$, respectively, under the $\rm U(1)_{L_μ-L_τ}$ gauge symmetry. These charge assignments allow a trilinear interaction between the two scalar fields, which is crucial for generating the DM mass splitting. Following the spontaneous breaking of the $\rm U(1)_{L_μ-L_τ}$ symmetry, with $S$ acquiring a vacuum expectation value and generating a mass for the BSM gauge boson $Z_{μτ}$, the real and imaginary components of $Φ$ acquire a mass splitting. This naturally gives rise to an inelastic DM scattering scenario that can accommodate the LZ excess. We perform a likelihood-based assessment of the sensitivity of the model parameters to the observed event while consistently accounting for other relevant phenomenological constraints. Finally, we discuss the prospects for probing the viable parameter space at future experiments.
Comments33 pages, 13 figures, and 1 table
