论文标题
Dans实验的新结果
New results from the DANSS experiment
论文作者
论文摘要
有几种实验迹象表明，无菌中微子在1 eV球场中具有质量，许多实验正在试图阐明情况。在6年中，DANSS实验收集了超过600万个反β衰减（IBD）事件，并在4个反应堆期间测量了背景水平。从3.1 GW $ _ {th} $反应堆的3.1 GW核心中心（10.9 m，11.9 m和12.9 m）以3距离（10.9 m，11.9 m和12.9 m）收集数据。通常每周经常更改检测器位置2-3次。因此，在分析中取消了许多系统的不确定性。在收集了另外70万个IBD事件之后，在4 $ν$案例中最佳拟合点的重要性从1.3 $σ$增加到2.35 $σ$。这仍然没有统计学意义，我们介绍了涵盖最有趣的无菌中微子参数范围的排除区域，最高为$ \ sin^22θ_{ee} <0.004 $。特别是，DANS不包括大部分的无菌中微子参数，而这些参数是最近的最佳结果，包括最佳拟合点。测量了对燃料组成的IBD速率依赖性。它与Huber-Mueller模型的预测一致。在将近6年的时间里，使用抗中型事件速率在2天内用$ \％$ $精度测量了反应堆功率，在初始时期对反应堆功率进行了归一化。
There are several experimental indications of sterile neutrinos with a mass in the 1 eV ballpark and many experiments are trying to clarify the situation. During 6 years the DANSS experiment collected more than 6 million Inverse Beta Decay (IBD) events and measured the background level during 4 reactor-off periods. Data were collected at 3 distances (10.9 m, 11.9 m, and 12.9 m) from the center of the core of a 3.1 GW$_{th}$ reactor with event rate up to 5 thousand per day. The detector position was changed frequently usually 2-3 times a week. Therefore many systematic uncertainties were canceled out in the analysis. After collection of additional 0.7 million IBD events the significance of the best-fit point in the 4$ν$ case increased from 1.3$σ$ to 2.35$σ$. This is still not statistically significant and we present the exclusion area that covers a very interesting range of the sterile neutrino parameters up to $\sin^22θ_{ee} < 0.004$ in the most sensitive point. In particular DANSS excludes a large fraction of sterile neutrino parameters preferred by the recent BEST results including the BEST best-fit point. The IBD rate dependence on the fuel composition was measured. It agrees with predictions of the Huber-Mueller model. During almost 6 years the reactor power was measured with $\approx1.8\%$ accuracy in 2 days using the anti-neutrino event rate normalized to the reactor power at the initial period.
