eCall是欧盟计划在2015年完成部署的一套车载自动紧急呼叫系统,在发生严重交通事故后,即使司机和乘客失去知觉不能拨打电话,这一系统也能够自动拨叫欧洲统一的紧急救援电话112,并报告事故车辆所处的位置。罗德与施瓦茨公司的R&S?CMW...eCall是欧盟计划在2015年完成部署的一套车载自动紧急呼叫系统,在发生严重交通事故后,即使司机和乘客失去知觉不能拨打电话,这一系统也能够自动拨叫欧洲统一的紧急救援电话112,并报告事故车辆所处的位置。罗德与施瓦茨公司的R&S?CMW500和R&S?SMBV100A仪表,配合R&S?CMWKA094 e Call应用软件,为客户提供了一套理想的e Call车载系统可靠性测试方案。展开更多
In this paper, we studied the development of hadronic shower in an electromagnetic calorimeter of Alpha Magnetic Spectrometer Ⅱ. Two parametrized empirical formulae were proposed to describe the hadronic shower shape...In this paper, we studied the development of hadronic shower in an electromagnetic calorimeter of Alpha Magnetic Spectrometer Ⅱ. Two parametrized empirical formulae were proposed to describe the hadronic shower shape in calorimeter. Using 100 GeV proton beam incident on the center of the ECAL, detailed plots of lateral and longitudinal hadronic shower behavior were given and we found the formulae can describe the development of the hadronic shower with the test beam data. The possible application of the parametrized formulae including e±-π± discrimination and tau jet reconstruction was discussed.展开更多
The process of Sb2Te3 thin film growth on the Pt substrate by electrochemical atomic layer epitaxy (ECALE) was studied. Cyclic voltammetric scanning was performed to analyze the electrochemical behavior of Te and Sb o...The process of Sb2Te3 thin film growth on the Pt substrate by electrochemical atomic layer epitaxy (ECALE) was studied. Cyclic voltammetric scanning was performed to analyze the electrochemical behavior of Te and Sb on the Pt substrate. Sb2Te3 film was formed using an automated flow deposition system by alternately depositing Te and Sb atomic layers for 400 circles. The deposited Sb2Te3 films were characterized by XRD, EDX, FTIR and FESEM observation. Sb2Te3 compound structure was confirmed by XRD pattern and agreed well with the results of EDX quantitative analysis and coulometric analysis. FESEM micrographs showed that the deposit was composed of fine nano particles with size of about 20 nm. FESEM image of the cross section showed that the deposited films were very smooth and dense with thickness of about 190 nm. The optical band gap of the deposited Sb2Te3 film was determined as 0.42 eV by FTIR spectroscopy, and it was blue shifted in comparison with that of the bulk Sb2Te3 single crystal due to its nanocrystalline microstructure.展开更多
We develop an empirical formula to parameterize the 3-dimension （3D） distribution of electromagnetic showers in the Alpha Magnetic Spectrometer Ⅱ electromagnetic calorimeter（ECAL）. The formula was verified by ECA...We develop an empirical formula to parameterize the 3-dimension （3D） distribution of electromagnetic showers in the Alpha Magnetic Spectrometer Ⅱ electromagnetic calorimeter（ECAL）. The formula was verified by ECAL test beam data in 2002 and found to perform well. The distribution of electron showers in the ECAL are well described by the formula, which has parameters that allow one to determine the 3D shape of electromagnetic showers in the ECAL. We use this formula to correct for lateral energy leakage and dead channels in the ECAL; good results are obtained.展开更多
Silicon photomultipliers （SiPMs） have remarkable advantages for use in photo-detection. Compared with PMT, SiPM shows advantages of high gain, excellent time resolution, insensitivity to magnetic fields and a lower ...Silicon photomultipliers （SiPMs） have remarkable advantages for use in photo-detection. Compared with PMT, SiPM shows advantages of high gain, excellent time resolution, insensitivity to magnetic fields and a lower operating voltage. SiPMs from Hamamatsu are used in the electromagnetic calorimeter （ECAL） sub-detector in the Positron Electron Balloon Spectrometer （PEBS） experiment, a balloon-borne spectrometer experiment aiming at the precise measurement of the cosmic-ray positron fraction. This paper introduces the evaluation and test results of several SiPM detector types, the dedicated front-end application specific integrated circuit （ASIC） electronics and the design of the data acquisition system （DAQ） system.展开更多
Background The circular electron positron collider(CEPC)was proposed as a future Higgs/Z factory.A sampling calo-rimeter with scintillator-tungsten sandwich structure(ScW)is selected as one of the electromagnetic calo...Background The circular electron positron collider(CEPC)was proposed as a future Higgs/Z factory.A sampling calo-rimeter with scintillator-tungsten sandwich structure(ScW)is selected as one of the electromagnetic calorimeter(ECAL)options.Its active layers consist of plastic scintillator strip units with a thickness of 2 mm and a size of 5×45 mm2,read out by silicon photomultipliers(SiPM).Purpose The light output has non-uniformity along the length direction of the scintillator strip,which affects the resolution of the ScW ECAL.It is necessary to control the non-uniformity to a low level.Methods We present the optimization of the scintillator units to improve the uniformity of the light output,including the light output distribution of the scintillator strips with different SiPM coupling configurations,and the impact of the coupling groove shape and dimension on the light output uniformity.Results and conclusion The results show that the non-uniformity of the scintillator unit with a runway-shaped coupling groove at the bottom-center of the strip can achieve 4%without reduction in the light output.Compared to the case of non-uniformity before optimization,the optimized uniformity improves the boson mass resolution about 23%based on the reconstruction of Higgs→γγ,which is comparable to the perfect homogeneous case.展开更多
文摘eCall是欧盟计划在2015年完成部署的一套车载自动紧急呼叫系统,在发生严重交通事故后,即使司机和乘客失去知觉不能拨打电话,这一系统也能够自动拨叫欧洲统一的紧急救援电话112,并报告事故车辆所处的位置。罗德与施瓦茨公司的R&S?CMW500和R&S?SMBV100A仪表,配合R&S?CMWKA094 e Call应用软件,为客户提供了一套理想的e Call车载系统可靠性测试方案。
基金Supported by National Natural Science Foundation of China (10435070,10721140381,10099630)China Ministry of Science and Technology (2007CB16101)Chinese Academy of Sciences (KJCX2-N17,1730911111)
文摘In this paper, we studied the development of hadronic shower in an electromagnetic calorimeter of Alpha Magnetic Spectrometer Ⅱ. Two parametrized empirical formulae were proposed to describe the hadronic shower shape in calorimeter. Using 100 GeV proton beam incident on the center of the ECAL, detailed plots of lateral and longitudinal hadronic shower behavior were given and we found the formulae can describe the development of the hadronic shower with the test beam data. The possible application of the parametrized formulae including e±-π± discrimination and tau jet reconstruction was discussed.
基金supported by the National Natural Science Foundation of China(Grant No.50401008)the Prophase Foundation for National Fundamental Research(Grant No.2004CCA03200)the Graduate Student Innovation Foundation of HUST.
文摘The process of Sb2Te3 thin film growth on the Pt substrate by electrochemical atomic layer epitaxy (ECALE) was studied. Cyclic voltammetric scanning was performed to analyze the electrochemical behavior of Te and Sb on the Pt substrate. Sb2Te3 film was formed using an automated flow deposition system by alternately depositing Te and Sb atomic layers for 400 circles. The deposited Sb2Te3 films were characterized by XRD, EDX, FTIR and FESEM observation. Sb2Te3 compound structure was confirmed by XRD pattern and agreed well with the results of EDX quantitative analysis and coulometric analysis. FESEM micrographs showed that the deposit was composed of fine nano particles with size of about 20 nm. FESEM image of the cross section showed that the deposited films were very smooth and dense with thickness of about 190 nm. The optical band gap of the deposited Sb2Te3 film was determined as 0.42 eV by FTIR spectroscopy, and it was blue shifted in comparison with that of the bulk Sb2Te3 single crystal due to its nanocrystalline microstructure.
基金Supported by NSFS(10099630),International S&T Collaboration Key Program,Ministry of Science and Technology of China
文摘We develop an empirical formula to parameterize the 3-dimension （3D） distribution of electromagnetic showers in the Alpha Magnetic Spectrometer Ⅱ electromagnetic calorimeter（ECAL）. The formula was verified by ECAL test beam data in 2002 and found to perform well. The distribution of electron showers in the ECAL are well described by the formula, which has parameters that allow one to determine the 3D shape of electromagnetic showers in the ECAL. We use this formula to correct for lateral energy leakage and dead channels in the ECAL; good results are obtained.
文摘Silicon photomultipliers （SiPMs） have remarkable advantages for use in photo-detection. Compared with PMT, SiPM shows advantages of high gain, excellent time resolution, insensitivity to magnetic fields and a lower operating voltage. SiPMs from Hamamatsu are used in the electromagnetic calorimeter （ECAL） sub-detector in the Positron Electron Balloon Spectrometer （PEBS） experiment, a balloon-borne spectrometer experiment aiming at the precise measurement of the cosmic-ray positron fraction. This paper introduces the evaluation and test results of several SiPM detector types, the dedicated front-end application specific integrated circuit （ASIC） electronics and the design of the data acquisition system （DAQ） system.
基金supported by National Key Programme for S&T Research and Development(Grant No.2016YFA0400400)National Natural Science Foundation of China(Grant No.11675196)supported in part by the CAS Centre for Excellence in Particle Physics(CCEPP)
文摘Background The circular electron positron collider(CEPC)was proposed as a future Higgs/Z factory.A sampling calo-rimeter with scintillator-tungsten sandwich structure(ScW)is selected as one of the electromagnetic calorimeter(ECAL)options.Its active layers consist of plastic scintillator strip units with a thickness of 2 mm and a size of 5×45 mm2,read out by silicon photomultipliers(SiPM).Purpose The light output has non-uniformity along the length direction of the scintillator strip,which affects the resolution of the ScW ECAL.It is necessary to control the non-uniformity to a low level.Methods We present the optimization of the scintillator units to improve the uniformity of the light output,including the light output distribution of the scintillator strips with different SiPM coupling configurations,and the impact of the coupling groove shape and dimension on the light output uniformity.Results and conclusion The results show that the non-uniformity of the scintillator unit with a runway-shaped coupling groove at the bottom-center of the strip can achieve 4%without reduction in the light output.Compared to the case of non-uniformity before optimization,the optimized uniformity improves the boson mass resolution about 23%based on the reconstruction of Higgs→γγ,which is comparable to the perfect homogeneous case.
