Water Quality Monitoring Analysis Based on WCDA
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摘要: 水切伦科夫探测器阵列（Water Cherenkov Detector Array，WCDA）是高海拔宇宙线观测站（Large High Altitude Air Shower Observatory，LHAASO）的主体探测器之一，水作为探测器的唯一探测介质，水的洁净度直接影响探测器对切伦科夫光的探测效率。为保证水切伦科夫探测器阵列物理目标的实现，水衰减长度的实时测量和监测至关重要，是探测器正常运行和标定的关键工作之一。分别介绍了水衰减长度测量装置和紫外可见分光光度计的工作原理，并通过不同波长的发光二极管（Light Emitting Diode，LED）对各种样品水进行测量，将两种方法的数据结果进行对比分析，得出两种装置的测量误差分别为0.22 m和0.18 m，以及工业指标吸光度与科研指标水衰减长度之间的对应关系，并为几何和跟踪（GEometry AND Tracking，GEANT4）模拟确定了一种Querry水质模型，进一步推进了模拟的真实化。通过对水切伦科夫探测器阵列1号水池水衰减测量装置的验证及从注水到稳定运行期间的水质监测的数据研究，总结了一套稳定可靠的水质监测方案，为2、3号水池的监测工作奠定了良好的基础。Abstract: The Water Cherenkov Detector Array (WCDA) is one of the main detectors of the High Altitude Cosmic Ray Observatory (LHAASO), with water as the only detection medium, the water transparency will directly affect the detection efficiency of Cherenkov Light. In order to ensure the realization of WCDA physical goals, the real-time measurement and monitoring of water attenuation length is very vital, which is one of the key tasks for the normal operation and calibration of the detector. In this experiment, the working principle of water attenuation length measuring device and ultraviolet-visible spectrophotometer is introduced, and various samples of water are measured by different wavelength LED, and the data results of the two methods are compared and analyzed. The measurement errors of the two devices are found to be 0.22m and 0.18m, the corresponding relationship between industrial index absorbance and water attenuation length of scientific research index is found, and a Querry water quality model for the GEANT4 simulation is established by simulation, which further promotes the realisation of simulation. Through the verification of WCDA No.1 water attenuation measuring device and the data study of water quality monitoring from water injection to stable operation, a set of stable and reliable water quality monitoring scheme is summarized, which provides a lot of help for the monitoring work of No.2 and No.3 water pools.
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Keywords:
- LHAASO /
- Water quality /
- Water attenuation /
- Absorbance
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[1] 中国科学院高能物理研究所, 中国科学院基础研究局. 西藏羊八井宇宙线国家野外观测研究站的建设、运行与发展[J]. 中国科学院院刊, 2010(4):461-464. [2] 曹臻, 刘加丽, 白云翔. 物理学中的世纪难题:高能宇宙线的起源之"谜"[J]. 自然杂志, 2009, 31(6):342-347, 363. [3] 曹臻, 陈明君, 陈松战, 等. 高海拔宇宙线观测站LHAASO概况[J]. 天文学报, 2019, 60(3):1-16. [4] AMAT F, BIZOUARD P, BRYANT J, et al. Measuring the attenuation length of water in the CHIPS-M water Cherenkov detector[J]. Nuclear Instruments and Methods in Physics Research Section A:Accelerators Sepctrometers Detectors and Associated Equipment, 2017, 844:108-115.
[5] 路浩奇. 大亚湾反符合水切伦科夫探测器及其模型研究[D]. 北京:中国科学院研究生院, 2009. [6] JONES B J P, CHIU C S, CONRAD J M, et al. A measurement of the absorption of liquid argon scintillation light by dissolved nitrogen at the part-per-million level[J]. Journal of Instrumentation, 2013, 8(7):1-19.
[7] ZUO X, XIAO G, FENG S H, et al. Design and performances of prototype muon detectors of LHAASO-KM2A[J]. Nuclear Instruments and Methods in Physics Research Section A:Accelerators, Spectrometers, Detectors and Associated Equipment, 2015, 789:143-149.
[8] LI C, XIAO G, FENG S H, et al. An apparatus to measure water optical attenuation length for LHAASO-MD[J]. Nuclear Instruments and Methods in Physics Research Section A:Accelerators, Spectrometers, Detectors and Associated Equipment, 2018, 892:122-126.
[9] LI H C, YAO Z G, YU C X, et al. A method to monitor and measure the water transparency in LHAASO-WCDA using cosmic muon signals[J]. Chinese Physics C, 2017, 41(2):145-152.
[10] LI H C, YAO Z G, CHEN M J, et al. Study on single-channel signals of water Cherenkov detector array for the LHAASO project[J]. Nuclear Instruments and Methods in Physics Research Section A:Accelerators, Spectrometers, Detectors and Associated Equipment, 2017, 854:107-112.
[11] STEVE J, SCOTT P. Optical absorption of water compendium[DB/OL].[2019-11-04]. http://omlc.org/spectra/water/abs/index.html.
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