用于低质量暗物质搜寻的双通道SiPM读出NaI(Tl)晶体的温度依赖性能
Temperature-Dependent Performance of NaI(Tl) Crystal with Dual-Channel SiPM Readout for Low-Mass Dark Matter Searches
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中文总结 AI 辅助
该研究表征了双通道SiPM读出NaI(Tl)晶体的温度依赖性能，发现低温下光产额提升且双通道可抑制热噪声，为降低暗物质等搜寻的能量阈值提供了关键路径。
中文摘要 AI 辅助
我们报道了首个用于稀有事件搜寻的、由两个硅光电倍增管（SiPM）直接耦合至NaI(Tl)晶体两端的读出结构的温度依赖特性表征。将尺寸为6 mm × 6 mm × 13 mm的NaI(Tl)晶体直接耦合至两个SiPM，在液氮冷却的低温恒温器中于94 K至293 K的温度范围内进行表征。使用²⁴¹Am源的γ射线峰测量光产额、能量分辨率和闪烁衰减时间。在校正光学串扰贡献后，光产额提升，在238 K时达到17.7 ± 1.1个光电子/keV，相对于室温（293 K）提升了34.5%。此外，双通道结构通过符合触发有效抑制随机热噪声，结合观测到的光产额提升，为降低暗物质及相干弹性中微子-原子核散射搜寻的能量阈值提供了关键途径。
英文摘要
We report the first temperature-dependent characterization of a NaI(Tl) crystal readout by two silicon photomultipliers (SiPMs) directly coupled to opposite ends of the crystal for rare-event searches. A $6 \text{ mm} \times 6 \text{ mm} \times 13 \text{ mm}$ NaI(Tl) crystal was directly coupled to two SiPMs and characterized in a liquid nitrogen-cooled cryostat over a temperature range of 94$-$293 K. The light yield, energy resolution, and scintillation decay time were measured using $γ$-ray peak from a $^{241}$Am source. After correcting for optical crosstalk contributions, the light yield increased, reaching $17.7 \pm 1.1$ photoelectrons/keV at 238 K, corresponding to a 34.5% enhancement relative to room temperature (293 K). Furthermore, dual-channel configuration effectively suppresses random thermal noise via coincidence triggers, which together with the observed increase in light yield, provides a critical pathway toward lowering the energy threshold for dark matter and coherent elastic neutrino$-$nucleus scattering searches.
