Projected WIMP sensitivity of the XENONnT dark matter experiment
Projected WIMP sensitivity of the XENONnT dark matter experiment
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DOI：
10.1088/1475-7516/2020/11/031
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发表时间：
2020-11-01
影响因子：
6.4
通讯作者：
Zopounidis, J. P.
中科院分区：
文献类型：
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作者：
Aprile, E.;Aalbers, J.;Zopounidis, J. P.
XENONnT是一个暗物质直接探测实验，利用5.9吨装有仪器的液体氙，位于INFN大萨索国家实验室。在这项工作中，我们预测的实验背景和项目的灵敏度XENONNT弱相互作用大质量粒子（WIMPs）的检测。感兴趣能量区域的预期平均差分背景率（对应于电子和核反冲的（1，13）keV和（4，50）keV）分别为12.3 +/- 0.6（keV t y）（-1）和（2.2 +/- 0.5）x 10（-3）（keV t y）（-1），在4 t基准质量中。我们使用轮廓构造方法计算统一的置信区间，以确保适当的覆盖率。在20 t y的曝光目标下，对于50 GeV/c（2）质量的WIMP，预期的自旋无关WIMP-核子相互作用的灵敏度达到1.4 x 10（-48）cm（2）的横截面，置信水平为90%，超过XENON 1 T设定的当前最佳极限一个数量级。此外，我们还发现，对于一个50 GeV/c（2）的WIMP，其截面大于2.6 x 10（-48）cm（2）（5.0 x 10（-48）cm（2）），发现XENONNT的意义中值超过3 sigma（5 sigma）。对自旋相关的WIMP与中子（质子）耦合的预期灵敏度达到2.2 x 10（-43）cm（2）（6.0 x 10（-42）cm（2））。
XENONnT is a dark matter direct detection experiment, utilizing 5.9 t of instrumented liquid xenon, located at the INFN Laboratori Nazionali del Gran Sasso. In this work, we predict the experimental background and project the sensitivity of XENONnT to the detection of weakly interacting massive particles (WIMPs). The expected average differential background rate in the energy region of interest, corresponding to (1, 13) keV and (4, 50) keV for electronic and nuclear recoils, amounts to 12.3 +/- 0.6 (keV t y)(-1) and (2.2 +/- 0.5) x 10(-3) (keV t y)(-1), respectively, in a 4t fiducial mass. We compute unified confidence intervals using the profile construction method, in order to ensure proper coverage. With the exposure goal of 20 t y, the expected sensitivity to spin-independent WIMP-nucleon interactions reaches a cross-section of 1.4 x 10(-48) cm(2) for a 50 GeV/c(2) mass WIMP at 90% confidence level, more than one order of magnitude beyond the current best limit, set by XENON1T. In addition, we show that for a 50 GeV/c(2) WIMP with cross-sections above 2.6 x 10(-48) cm(2) (5.0 x 10(-48) cm(2)) the median XENONnT discovery significance exceeds 3 sigma (5 sigma). The expected sensitivity to the spin-dependent WIMP coupling to neutrons (protons) reaches 2.2 x 10(-43) cm(2) (6.0 x 10(-42) cm(2)).