Background Liquid Argon(LAr)is used as a target material in several current and planned experiments related to dark matter direct searching and neutrino detection.Argon provides excellent pulse shape discrimination(PS...Background Liquid Argon(LAr)is used as a target material in several current and planned experiments related to dark matter direct searching and neutrino detection.Argon provides excellent pulse shape discrimination(PSD)capability,which could separate the electron recoil backgrounds from the expected nuclear recoil signals.As the next-generation photosensors,silicon photon multiplier(SiPM)is expected to replace traditional photon multiplier tubes.Purpose The purpose of this paper is to compare the PSD capability of a LAr detector between using SiPMs as photosensors and using PMTs as photosensors.Methods The PSD capability of a LAr detector is determined through the prompt fraction method,which relies on the analysis of output pulses.These pulses are generated using Monte Carlo simulation,incorporating real single photoelectron pulses obtained from a PMT or a SiPM.Results Three kinds of SiPMs and one kind of PMT have been used to compare the PSD capability of a LAr detector.The use of J-60035 SiPM results in a better PSD capability compared to the use of PMT as a photosensor,while using the other two kinds of SiPM deteriorates the PSD capability.Conclusion SiPM is a promising photosensor candidate for a LAr detector.The better energy resolution could help to improve its PSD capability,while the higher probabilities of cross-talk and after-pulse degrade its PSD capability.Notably,after-pulse has a more significant impact compared to cross-talk because after-pulse influences the energy distribution within the time window,while cross-talk primarily affects the energy resolution of the detector.展开更多
采用硫酸水解超细纤维合成革基布,暴露基布的活性基团;以鞣剂F-90作为交联剂,将胶原蛋白接枝到超细纤维合成革基布上,以期改善基布的卫生性能。结果表明:最佳改性工艺条件为:胶原蛋白用量15%、F-90用量6%、改性温度45℃、时间4 h、体系p...采用硫酸水解超细纤维合成革基布,暴露基布的活性基团;以鞣剂F-90作为交联剂,将胶原蛋白接枝到超细纤维合成革基布上,以期改善基布的卫生性能。结果表明:最佳改性工艺条件为:胶原蛋白用量15%、F-90用量6%、改性温度45℃、时间4 h、体系p H 7.0;该条件下处理后,基布的羧基含量增加188.82%,氨基含量增加124.19%,透水汽性提高65.15%,吸水性提高58.04%,且其抗张强度、断裂伸长率和撕裂强度均有所提高。采用FI-IR、XPS、SEM和接触角分别对改性前后基布进行表征,结果显示:胶原蛋白能够成功交联改性到基布上,改性后基布表面的活性基团增加,纤维松散程度增大,润湿性提高。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12275289,11975257,and 12175247)the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2023015)the National Key R&D Program of China(Grant No.2016YFA0400304).
文摘Background Liquid Argon(LAr)is used as a target material in several current and planned experiments related to dark matter direct searching and neutrino detection.Argon provides excellent pulse shape discrimination(PSD)capability,which could separate the electron recoil backgrounds from the expected nuclear recoil signals.As the next-generation photosensors,silicon photon multiplier(SiPM)is expected to replace traditional photon multiplier tubes.Purpose The purpose of this paper is to compare the PSD capability of a LAr detector between using SiPMs as photosensors and using PMTs as photosensors.Methods The PSD capability of a LAr detector is determined through the prompt fraction method,which relies on the analysis of output pulses.These pulses are generated using Monte Carlo simulation,incorporating real single photoelectron pulses obtained from a PMT or a SiPM.Results Three kinds of SiPMs and one kind of PMT have been used to compare the PSD capability of a LAr detector.The use of J-60035 SiPM results in a better PSD capability compared to the use of PMT as a photosensor,while using the other two kinds of SiPM deteriorates the PSD capability.Conclusion SiPM is a promising photosensor candidate for a LAr detector.The better energy resolution could help to improve its PSD capability,while the higher probabilities of cross-talk and after-pulse degrade its PSD capability.Notably,after-pulse has a more significant impact compared to cross-talk because after-pulse influences the energy distribution within the time window,while cross-talk primarily affects the energy resolution of the detector.
文摘采用硫酸水解超细纤维合成革基布,暴露基布的活性基团;以鞣剂F-90作为交联剂,将胶原蛋白接枝到超细纤维合成革基布上,以期改善基布的卫生性能。结果表明:最佳改性工艺条件为:胶原蛋白用量15%、F-90用量6%、改性温度45℃、时间4 h、体系p H 7.0;该条件下处理后,基布的羧基含量增加188.82%,氨基含量增加124.19%,透水汽性提高65.15%,吸水性提高58.04%,且其抗张强度、断裂伸长率和撕裂强度均有所提高。采用FI-IR、XPS、SEM和接触角分别对改性前后基布进行表征,结果显示:胶原蛋白能够成功交联改性到基布上,改性后基布表面的活性基团增加,纤维松散程度增大,润湿性提高。