论文标题
改进了β衰减背景的液体氙气检测器中新物理学的计算
Improved calculations of beta decay backgrounds to new physics in liquid xenon detectors
论文作者
论文摘要
我们为地基州对$^{214} $ pb，$^{212} $ pb和$^{85} $ kr的电子能量光谱提出了高精度的理论预测。核结构对光谱形状的影响使用大规模的壳模型计算。最终光谱还包括原子筛选和交换效果。核结构对$^{214} $ pb的影响和$^{212} $ pb光谱低于$ \ $ \ of100 $ kev，与单独的原子效应相对较大。我们发现，$^{214} $ pb（$^{212} $ pb）的完整计算预测，与使用频谱相比，在1-15 keV能量的频谱中，在使用允许的频谱中计算出的频谱中的频谱中，在使用允许的过渡时，使用范围为$ g g g g g g g g g g g g g g g的15.0-23.2％（12.1-19.0％）的事件率降低了。这种差异突出了适当的理论治疗方法的重要性，又是对这些光谱进行直接测量的需求，以彻底了解将来的实验中的$β$衰减背景。
We present high-precision theoretical predictions for the electron energy spectra for the ground-state to ground-state $β$ decays of $^{214}$Pb, $^{212}$Pb, and $^{85}$Kr most relevant to the background of liquid xenon dark matter detectors. The effects of nuclear structure on the spectral shapes are taken into account using large-scale shell model calculations. Final spectra also include atomic screening and exchange effects. The impact of nuclear structure effects on the $^{214}$Pb and $^{212}$Pb spectra below $\approx100$ keV, pertinent for several searches for new physics, are found to be comparatively larger than those from the atomic effects alone. We find that the full calculation for $^{214}$Pb ($^{212}$Pb) predicts 15.0-23.2% (12.1-19.0%) less event rate in a 1-15 keV energy region of interest compared to the spectrum calculated as an allowed transition when using values of the weak axial vector coupling in the range $g_{\rm A}=0.7-1.0$. The discrepancy highlights the importance of both a proper theoretical treatment and the need for direct measurements of these spectra for a thorough understanding of $β$ decay backgrounds in future experiments.
