发表机构
Stockholm University; The Oskar Klein Centre for Cosmoparticle Physics; Universidad Autónoma de Madrid; Instituto de Física Teórica UAM-CSIC（斯德哥尔摩大学; 奥斯卡·克莱因宇宙粒子物理中心; 马德里自治大学; UAM-CSIC理论物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用费米-LAT Pass 8数据搜寻邻近暗物质子晕候选体的伽马射线线信号，未发现显著证据，推导了χχ→γγ湮灭截面的95%置信上限，约束了WIMP模型的相关参数区域。
AI 中文摘要
我们对近期提出的一个邻近暗物质子晕候选体的单色伽马射线发射开展了专项搜寻。利用近15年的费米-LAT Pass 8数据，我们在10至300 GeV能量范围内对伽马射线线进行滑动窗搜寻，未发现任何统计显著的线信号证据。最大超出量出现在E_γ≈28 GeV处，局部显著性为2.5σ。因此，我们对χχ→γγ的湮灭截面推导了95%置信水平的上限。在假设的NFW子晕模型下，所得约束在大部分探索质量范围内强于现有的银心线约束。我们进一步将这些线约束转化为对动机充分的WIMP模型的限制，例如希格斯门户和Wino暗物质场景，限制了与热退耦一致的先前开放参数区域，以及与银心超出量的暗物质解释相关的模型。
英文摘要
We present a dedicated search for monochromatic gamma-ray emission from a recently proposed nearby dark matter subhalo candidate. Using nearly 15 years of Fermi-LAT Pass 8 data, we perform a sliding-window search for gamma-ray lines between 10 and 300 GeV. We do not find any statistically significant evidence for a line signal. The largest excess occurs at $E_γ\simeq 28 \, {\rm GeV}$ with a local significance of $2.5σ$. We therefore derive 95% confidence level upper limits on the annihilation cross section for $χχ\rightarrow γγ$. Under the assumed NFW subhalo model, the resulting constraints are stronger than existing Galactic Center line limits over much of the explored mass range. We further translate these line constraints into bounds on well-motivated WIMP models, such as Higgs-portal and Wino dark matter scenarios, restricting previously open parameter regions consistent with thermal freeze-out as well as models associated with dark matter interpretations of the Galactic Center Excess.
Comments10 pages, 9 figures
