论文标题
从SNOLAB处的11 kg天目标暴露的低质量相互作用的较弱相互作用的巨大颗粒
Results on Low-Mass Weakly Interacting Massive Particles from an 11 kg-day Target Exposure of DAMIC at SNOLAB
论文作者
论文摘要
我们对在Snolab Underground实验室的11 kg天目标暴露中呈现出弱相互作用的巨大颗粒（WIMP）的限制。在DAMIC CCD中观察到的具有电子等效能量的电离事件的能量和空间分布$> $ 200 eV $ _ {\ rm EE} $与自然放射性的背景一致。在分析阈值50 eV $ _ {\ rm ee} $上方观察到过多的电离事件。尽管这种低能量过剩的起源需要进一步调查，但我们的数据排除了与旋转无关的WIMP-NUCLEON散射横截面$σ_{χ-n} $低至$ 3 \ times 10^{ - 41} $ cm $ $ $^2 $，质量为7 geev $ c $ c $ c $ c^$ c^$ c^2 $。这些结果是硅目标对具有$M_χ$$ <$ 9 GEV $ C^{ - 2} $的wimps的最强限制，并且与2013年CDMS Silicon实验观察到的过量核能事件的任何暗物质解释都直接相关。
We present constraints on the existence of weakly interacting massive particles (WIMPs) from an 11 kg-day target exposure of the DAMIC experiment at the SNOLAB underground laboratory. The observed energy spectrum and spatial distribution of ionization events with electron-equivalent energies $>$200 eV$_{\rm ee}$ in the DAMIC CCDs are consistent with backgrounds from natural radioactivity. An excess of ionization events is observed above the analysis threshold of 50 eV$_{\rm ee}$. While the origin of this low-energy excess requires further investigation, our data exclude spin-independent WIMP-nucleon scattering cross sections $σ_{χ-n}$ as low as $3\times 10^{-41}$ cm$^2$ for WIMPs with masses $m_χ$ from 7 to 10 GeV$c^{-2}$ . These results are the strongest constraints from a silicon target on the existence of WIMPs with $m_χ$$<$9 GeV$c^{-2}$ and are directly relevant to any dark matter interpretation of the excess of nuclear-recoil events observed by the CDMS silicon experiment in 2013.
