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arXiv 1601.05935physics.ins-dethep-ex
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GERDA实验中μ子否决的性能

The Performance of the Muon Veto of the GERDA Experiment

K. Freund, R. Falkenstein, P. Grabmayr, A. Hegai, J. Jochum, M. Knapp, B. Lubsandorzhiev, F. Ritter, C. Schmitt, A. -K. Schütz, I. Jitnikov, E. Shevchik, M. Shi… 展开作者

K. Freund, R. Falkenstein, P. Grabmayr, A. Hegai, J. Jochum, M. Knapp, B. Lubsandorzhiev, F. Ritter, C. Schmitt, A. -K. Schütz, I. Jitnikov, E. Shevchik, M. Shirchenko, D. Zinatulina

摘要:

低本底实验需要抑制宇宙起源引起的事件。位于LNGS的GERDA实验正在寻找$^{76}$ Ge的无中微子双β衰变。它配备了一个积极的μ子否决权,其中的主要部分是一个水切伦科夫否决权,在围绕GERDA低温恒温器的水箱中有66个PMT。利用该系统已记录了806个活日,其中491天是μ子-锗组合数据。通过蒙特卡罗模拟,对μ子在锗探测器中的沉积能量进行了模拟,得到μ子的探测效率为$\varepsilon_{μd}=(99.935\pm0.015)$ %.通过检验μ子-锗的符合事例,发现了$\varepsilon_{μr}=(99.2_{-0.4}^{+0.3})$的排斥效率,在没有否决条件的情况下,μ子本身在$Q_{ββ}$上产生$\textrm{BI}_μ=(3.16 \pm 0.85)\times10^{-3}$ cts/(keVPDMATHABMQ kg $\cdot$ yr)的本底指数。

英文摘要:

Low background experiments need a suppression of cosmogenically induced events. The GERDA experiment located at LNGS is searching for the neutrinless double beta decay of $^{76}$Ge. It is equipped with an active muon veto the main part of which is a water Cherenkov veto with 66 PMTs in the watertank surrounding the GERDA cryostat. With this system 806 live days have been recorded, 491 days were combined muon-germanium data. A muon detection efficiency of $\varepsilon_{μd}=(99.935\pm0.015)$ \% was found in a Monte Carlo simulation for the muons depositing energy in the germanium detectors. By examining coincident muon-germanium events a rejection efficiency of $\varepsilon_{μr}=(99.2_{-0.4}^{+0.3})$ \% was found. Without veto condition the muons by themselves would cause a background index of $\textrm{BI}_μ=(3.16 \pm 0.85)\times10^{-3}$ cts/(keV$\cdot$kg$\cdot$yr) at $Q_{ββ}$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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