Considering the effects of aging on the existing Inner Drift Chamber （IDC） of BESIII, a GEM-based inner tracker, the Cylindrical-GEM Inner Tracker （CGEM-IT）, is proposed to be designed and constructed as an upgrad...Considering the effects of aging on the existing Inner Drift Chamber （IDC） of BESIII, a GEM-based inner tracker, the Cylindrical-GEM Inner Tracker （CGEM-IT）, is proposed to be designed and constructed as an upgrade candidate for the IDC. This paper introduces a full simulation package for the CGEM-IT with a simplified digitization model, and describes the development of software for cluster reconstruction and track fitting, using a track fitting algorithm based on the Kalman filter method. Preliminary results for the reconstruction algorithms which are obtained using a Monte Carlo sample of single muon events in the CGEM-IT, show that the CGEM-IT has comparable momentum resolution and transverse vertex resolution to the IDC, and a better z-direction resolution than the IDC.展开更多
The relative differences in coordinates of Cylindrical Gas Electron Multiplier Detector-based Inner Tracker（CGEM-IT） clusters are studied to search for track segments in CGEM-IT for the BESIII experiment.With the fu...The relative differences in coordinates of Cylindrical Gas Electron Multiplier Detector-based Inner Tracker（CGEM-IT） clusters are studied to search for track segments in CGEM-IT for the BESIII experiment.With the full simulation of single muon track samples, clear patterns are found and parameterized for the correct cluster combinations. The cluster combinations satisfying the patterns are selected as track segment candidates in CGEM-IT with an efficiency higher than 99%. The parameters of the track segments are obtained by a helix fitting.Some χ^2 quantities, evaluating the differences in track parameters between the track segments in CGEM-IT and the tracks found in the outer drift chamber, are calculated and used to match them. Proper χ^2 requirements are determined as a function of transverse momentum and the matching efficiency is found to be reasonable.展开更多
近年来CGEM(可计算一般均衡模型,Computable General Equilibrium Model)日益受到重视。世界银行和国际劳工组织(ILO)进行了大量研究工作。所有的发达国家和许多发展中国家都建立了自己的CGE模型。人们用CGEM来描述市场,实现政策模拟,...近年来CGEM(可计算一般均衡模型,Computable General Equilibrium Model)日益受到重视。世界银行和国际劳工组织(ILO)进行了大量研究工作。所有的发达国家和许多发展中国家都建立了自己的CGE模型。人们用CGEM来描述市场,实现政策模拟,使其成为有力的政策研究工具。CGEM的应用领域,已经涉及到国际贸易、税制变更。展开更多
基金Supported by National Key Basic Research Program of China(2015CB856700)National Natural Science Foundation of China(11205184,11205182)Joint Funds of National Natural Science Foundation of China(U1232201)
文摘Considering the effects of aging on the existing Inner Drift Chamber （IDC） of BESIII, a GEM-based inner tracker, the Cylindrical-GEM Inner Tracker （CGEM-IT）, is proposed to be designed and constructed as an upgrade candidate for the IDC. This paper introduces a full simulation package for the CGEM-IT with a simplified digitization model, and describes the development of software for cluster reconstruction and track fitting, using a track fitting algorithm based on the Kalman filter method. Preliminary results for the reconstruction algorithms which are obtained using a Monte Carlo sample of single muon events in the CGEM-IT, show that the CGEM-IT has comparable momentum resolution and transverse vertex resolution to the IDC, and a better z-direction resolution than the IDC.
基金Supported by National Key Basic Research Program of China(2015CB856706)National Natural Science Foundation of China(11575222,11205184,11205182,11121092,11475185)Joint Funds of National Natural Science Foundation of China(U1232201)
文摘The relative differences in coordinates of Cylindrical Gas Electron Multiplier Detector-based Inner Tracker（CGEM-IT） clusters are studied to search for track segments in CGEM-IT for the BESIII experiment.With the full simulation of single muon track samples, clear patterns are found and parameterized for the correct cluster combinations. The cluster combinations satisfying the patterns are selected as track segment candidates in CGEM-IT with an efficiency higher than 99%. The parameters of the track segments are obtained by a helix fitting.Some χ^2 quantities, evaluating the differences in track parameters between the track segments in CGEM-IT and the tracks found in the outer drift chamber, are calculated and used to match them. Proper χ^2 requirements are determined as a function of transverse momentum and the matching efficiency is found to be reasonable.
文摘近年来CGEM(可计算一般均衡模型,Computable General Equilibrium Model)日益受到重视。世界银行和国际劳工组织(ILO)进行了大量研究工作。所有的发达国家和许多发展中国家都建立了自己的CGE模型。人们用CGEM来描述市场,实现政策模拟,使其成为有力的政策研究工具。CGEM的应用领域,已经涉及到国际贸易、税制变更。
