Dark matter interpretation of excesses in multiple direct detection experiments
Dark matter interpretation of excesses in multiple direct detection experiments
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DOI：
10.1103/physrevd.102.015017
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发表时间：
2020-02
影响因子：
5
通讯作者：
N. Kurinsky;D. Baxter;Y. Kahn;G. Krnjaic
中科院分区：
文献类型：
--
作者：
N. Kurinsky;D. Baxter;Y. Kahn;G. Krnjaic
我们提出了一个新的统一的解释，利用单电子阈值半导体探测器的暗物质直接探测实验中观察到的过量事件率。尽管它们的位置不同，曝光，读出技术，探测器组成，和操作深度，这些实验都观察到统计上显着的超额事件率为$\sim $10 Hz/kg。然而，这些持续的过量还没有被报道为暗物质信号，因为单独地，每一个都可以归因于不同的动机良好但未建模的背景，并且放在一起，它们不能用暗物质粒子弹性散射探测器核或电子来解释。我们表明，这些结果可以调和，如果半导体探测器看到一个集体的非弹性过程，与激发等离子体激元一致。我们进一步表明，等离子体激元激发可能会出现在两个引人注目的暗物质的情况下，这两个都可以解释现有的信号过剩率在锗，至少在数量级水平，在几个单电子阈值探测器。至少有一种情况下，也产生正确的文物密度从热冻结。这两种暗物质的情况激发了对最近实验中暗物质-电子散射的标准解释的彻底反思。
We present a novel unifying interpretation of excess event rates observed in several dark matter direct-detection experiments that utilize single-electron threshold semiconductor detectors. Despite their different locations, exposures, readout techniques, detector composition, and operating depths, these experiments all observe statistically significant excess event rates of $\sim$ 10 Hz/kg. However, none of these persistent excesses has yet been reported as a dark matter signal because individually, each can be attributed to different well-motivated but unmodeled backgrounds, and taken together, they cannot be explained by dark matter particles scattering elastically off detector nuclei or electrons. We show that these results can be reconciled if the semiconductor detectors are seeing a collective inelastic process, consistent with exciting a plasmon. We further show that plasmon excitation could arise in two compelling dark matter scenarios, both of which can explain rates of existing signal excesses in germanium and, at least at the order of magnitude level, across several single-electron threshold detectors. At least one of these scenarios also yields the correct relic density from thermal freeze-out. Both dark matter scenarios motivate a radical rethinking of the standard interpretations of dark matter-electron scattering from recent experiments.