发表机构
Istituto Nazionale di Fisica Nucleare, Sezione di Torino; Technical University of Munich, TUM School of Natural Sciences, Department of Physics（意大利国家核物理研究所都灵分部; 慕尼黑工业大学自然科学学院物理系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文利用太阳俘获约束检验LZ事件的非弹性暗物质解释，排除热希格斯子，但赝狄拉克费米子和亲中子散射模型仍可解释该候选事件。
AI 中文摘要
LUX-ZEPLIN（LZ）合作组报告了一个248 keV的核反冲候选事件，对于该事件，吸热暗物质（DM）给出了部分最大的局部显著性。我们研究了太阳俘获对三种简单解释的约束：热希格斯子（thermal Higgsino）、具有非对角矢量相互作用的赝狄拉克费米子（pseudo-Dirac fermion），以及通过O_4算子的亲中子吸热自旋相关散射。典型的全密度热希格斯子被排除：其在约0.38 MeV附近的LZ偏好劈裂低于IceCube的要求δ≳0.51–0.56 MeV。对于赝狄拉克基准模型，我们发现C_⊙=1.48×10^20 s^-1，但两态动力学强烈抑制了湮灭。包括热辅助的χ_1→χ_2再激发，给出最大Γ_A≃4.1×10^14 s^-1，比采用的IceCube b bbar极限低约1.8×10^5倍。对于m_χ=1 TeV、δ=300 keV的亲中子O_4散射，有限温度俘获给出C_⊙=3.98×10^17 s^-1，自旋响应范围为(1.77–9.72)×10^17 s^-1。即使在平衡状态下，上边缘仍比采用的b bbar极限低约154倍，而激进的无限q抑制加自旋上限压力测试仍留下约19倍的差距。b bbar映射被用作两个非希格斯子基准模型的代表性强子模板。因此，太阳俘获排除了热希格斯子解释，但并未普遍排除LZ候选事件的吸热解释。
英文摘要
The LUX-ZEPLIN (LZ) Collaboration has reported a $248$ keV nuclear-recoil candidate for which endothermic dark matter (DM) gives some of the largest local significances. We study Solar-capture constraints on three interpretations: a thermal Higgsino, a thermal pseudo-Dirac fermion with off-diagonal vector interactions, and neutron-philic endothermic spin-dependent scattering through $\mathcal{O}_4$. The canonical full-density thermal Higgsino is excluded: its LZ-preferred splitting near $0.38\,\mathrm{MeV}$ lies well below the splitting required to suppress Solar capture sufficiently to satisfy the IceCube upper limits on DM annihilation in the Sun, $δ\gtrsim0.51$-$0.56\,\mathrm{MeV}$. For the pseudo-Dirac benchmark parameters that fit the LZ event, we find $C_\odot=1.53\times10^{20}\,\mathrm{s}^{-1}$, while two-state kinetics limits the fixed-orbit annihilation rate to $Γ_A\lesssim4.4\times10^{14}\,\mathrm{s}^{-1}$, about $1.7\times10^5$ below the IceCube upper limit for the $b\bar b$ channel. A semi-analytic treatment indicates that re-excitation cycles further cool the captured population, although a full phase-space calculation is required for its final distribution. For neutron-philic $\mathcal{O}_4$ scattering at $m_χ=1$ TeV and $δ=300$ keV, finite-temperature capture gives $C_\odot=3.98\times10^{17}\,\mathrm{s}^{-1}$, with nuclear-structure uncertainties giving an envelope $(1.77$-$9.72)\times10^{17}\,\mathrm{s}^{-1}$. Under the equilibrium assumption, the upper edge remains about a factor $154$ below the IceCube upper limit for the $b\bar b$ channel. We use $b\bar b$ only as a soft-hadronic proxy because an exact constraint requires the model-specific annihilation spectrum. Solar capture therefore excludes the thermal-Higgsino interpretation but not endothermic explanations generically.
Comments43 pages, 14 figures and 3 tables. Comments are welcome
