共查询到20条相似文献,搜索用时 765 毫秒
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吴义根 陈国明 陈和生 张守宇 唐孝威 童国梁 M.Bocciolini C.Civinini R.D''alessandro M.Meschini M.Pieri P.Spillantini 王贻芳 H.Hofer P.LeCoultre B.Spiess J.Ulbricht 《中国物理 C》1991,15(10):865-874
本文介绍子配有BGO(锗酸铋)晶体阵列的L3铀强子量能器性能的模拟测试.对L3强子量能器以及测试实验作了简要介绍,并给出了该量能器对4—20GeV能量范围的π介子的能量分辨率、e/π响应比、角分辨、能量分辨率随入射π介子方向的变化以及强子穿透率等实验结果. 相似文献
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根据高温超导体层状结构特点和层间耦合效应,提出了一个唯象的S-N双层高 温超导模型(S表示超导层,N表示非超导层),并在Nambu空间求得高温超导态的格林函数,得到了S-N模型下高温超导体临界温度T_c随S,N层间耦合强度增加而下降的结果.在该 模型的基础上讨论了YBCO材料中Ba位替代对Tc的抑制效应,说明了高温超导体角分辨光电子能谱具有hump/dip/peak结构的特点,所得结果与实验相一致.
关键词:
层间耦合效应
替代效应
势无序
角分辨光电子能谱 相似文献
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WANG Xiao-Bin CHEN Guo-Ming LI Zu-Hao CHEN Gang YANG Ming YANG Zhao-Yu ZHANG Shao-He LU Yu-Sheng CHEN He-Sheng 《中国物理C(英文版)》2005,29(11):1071-1076
Analyzing methods on the angular resolution of lead-scintillating fiber electromagnetic calorimeter are studied. The space resolution function, which is used to calculate weights,is extracted from Monte-Carlo simulation. Better angular resolution was obtained from the beam test data of AMS ECAL in 2002 at CERN, when the space resolution function was used in the fit. Different ways to calculate the centers of gravity,to choose the layers to fit the incidence direction are also discussed. 相似文献
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In this paper, digital holographic (DH) microscopy demonstrates its ability to perform a full characterization of nanofibers. The high resolution and magnification of the presented method to study the nanofibers are tested using standard MIL-STD-150A 1951 USAF resolution test target. In this investigation, aggregated natural cellulose nanowhisker fibers are positioned in the front of the microscopic objective using a 3D translation stage in the object arm of DH setup. The recorded off-axis holograms are refocused using the angular spectrum method. The reconstructed complex field is used to calculate optical phase and intensity distributions of the object at different reconstruction depths. A simple algorithm is used to define the focused image with suitable accuracy. The dimensions and orientation of the fibers can be evaluated from the optical field at different depths. Then, the shape and textures along the aggregated natural cellulose nanowhisker fiber can be presented in a 3D space. 相似文献
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The effects of surface resistivity of the high voltage provider on the space dispersion of the induced charge of a prototype Resistive Plate Chamber (RPC) have been studied experimentally and theoretically. The results of both experiment and theory agree and confirm that a two-Gaussian function can be used to fit the dispersion of the induced charge of the RPC. It is shown that the Gaussian function with the narrower width is mainly due to the expansion of the avalanche charge in the gas gap of the RPC, and the Gaussian function with the larger width is due to the charge dispersion when it passes through the resistive carbon film. This will be useful in the RPC design when one wants to make an RPC with high position resolution. 相似文献
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中子散射成像技术是近年来国外正在发展的一项新型辐射成像技术, 在深空宇宙探测、核材料监控等方面具有广阔的应用前景. 角分辨是衡量该技术成像能力的一项重要参数. 研究了位置不确定度和能量分辨对角分辨的影响. 理论分析表明: 以不同角度散射, 成像的角分辨不同; 位置不确定不仅直接影响角分辨, 还通过影响能量不确定度对角分辨间接贡献; 位置分辨主要来源于探测器的结构尺寸, 当探测器尺寸小于5 cm, 影响角分辨的主要来源是能量不确定度. 利用所获得的理论结果指导设计了原理探测系统, 并对设计的原理系统开展了初步实验研究. 结果表明, 分析结果与实验得到的角分辨参数基本一致. 相似文献
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The Neighbor Cell Deposited Energy Ratio (NCDER) is a new method that is proposed to reconstruct incidence position in a single layer for a 3-dimensional imaging electromagnetic calorimeter (ECAL). This method was applied to reconstruct the ECAL test beam data for the Alpha Magnetic Spectrometer-02 (AMS-02). The results show that this method can achieve an angular resolution of 7.36±0.08°/√E+0.28±0.02° in the determination of the photon's direction, which is much more precise than that obtained with the commonly-adopted Center of Gravity (COG) method (8.4±0.1°/E+0.8±0.3°). Furthermore, since it uses only the properties of electromagnetic showers, this new method could also be used for other type of fine grain sampling calorimeters. 相似文献
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Cheol-Ho Jeong 《Applied Acoustics》2009,70(1):120-128
In the simulation of acoustic response of a room, one cannot satisfactorily estimate the transfer function or the impulse response with a sparse frequency resolution. We have studied about the frequency resolution for a satisfactory estimation of room transfer function or the reverberation time using the phased beam tracing method. In order to investigate what happens with the frequency resolution, a number of frequency resolution (0.01-1 Hz), which are usually employed in the numerical analysis, was tested for a room model. It was found that the total accumulated phase in a transfer function and the late part of an impulse response of a room are influenced by the frequency resolution. Main reason for the difference is the correct detection of non-minimum phase zeros, depending on the frequency resolution. A criterion for a proper frequency resolution was suggested by considering the modal density of three-dimensional space. When a sparse dataset was initially given, we showed that cubic spline interpolation can be used to enhance the precision of detection for non-minimum phase zeros. 相似文献
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动载体光电成像系统视轴稳定精度研究 总被引:4,自引:2,他引:2
载体扰动会对光电成像系统的性能产生影响.分析载体扰动的特点及产生的原因,主要分析载体角运动对光电成像系统性能的影响.在此基础上从空间分辨率、人眼观察性能以及跟踪精度3个方面分析光电成像系统对视轴稳定精度的要求,指出对于探测器限制的光电成像系统,应将积分时间内载体的角扰动控制在探测器限制的空间分辨率内,或将像移控制在一个探测单元尺寸内,对于衍射限制的光电成像系统,应将积分时间内载体的角扰动控制在衍射限制的空间分辨率内,得出了视轴稳定精度必须在满足成像系统空间分辨率的基础上,根据实际功能需求进行确定的结论.最后通过实例验证了上述结果. 相似文献