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1.
"嫦娥一号"卫星是我国的第一颗月球探测卫星,运行轨道高度为200 km,预计工作寿命为一年,其上配备的X射线成像谱仪具备了对月表进行X射线探测、成像和对太阳X射线进行监测的功能.该X射线谱仪由两个全同的探测器阵列组成,其中,为了实现对月表主要化学元素分布及其含量进行探测的科学目标,在每个探测器阵列还配备了2个低能探测器单元.这4路低能探测器单元的面积为25 mm2,采用的都是厚度为500 μm,具有优良探测性能的Si-PIN探测器,其探测能区为1~10 keV,能量分辨率为~5%@5.9 kev.文章主要介绍了嫦娥一号卫星X射线谱仪的地面验证实验,并且根据X射线谱仪的能量响应矩阵,利用直接解调方法和基本参数法对X射线谱仪地面验证实验中的探测数据,特别是对盲测样品中的Mg,Al,Si等元素进行了定性和定量分析.  相似文献   
2.
在领头阶和αs 修正阶 ,用QCD因子化方法 ,并对它的软胶子效应用光锥QCD求和规则分析D+ → K0 K+ 衰变过程 ,我们分析发现朴素因子化方法的结果远离实验结果 ,QCD因子化方法结果靠近实验结果 ,但是 ,在QCD因子化方法中 ,若考虑软胶子效应 ,其结果与实验结果相一致 .另外 ,计算发现 ,软胶子效应在该衰变道中有相当大的贡献 ,因此不能被忽略  相似文献   
3.
<正>离HXMT发射的日子越来越近。心里有许多期待,又有说不出的忐忑。虽然历经多次试验、测试,状态确认了再确认,操作谨慎了再谨慎,在等待的日子里,仍然过的提心吊胆,用航天人常用的说法叫"如履薄冰"。心里也总还是会想以前出现过哪些问题?那些解决了的问题还是不是问题?总在文字中看到这样的说法,成功道路上所历经的坎坷,都是我们人生词典中所不可或缺的因素,也是我们每个人生活经历中,不想遇到又不得不面对的。  相似文献   
4.
A prototype of the ME readout electronics onboard the Hard X-ray Modulate Telescope (HXMT) satellite is developed. Application Specific Integrated Chip (ASIC) is used to construct the front end electronics due to a large number of detectors. Field Programmable Gate Array (FPGA) is connected to the ASIC as a state machine controller and data FIFO in the DAQ system. A USB board is designed to communicate between the DAQ system and the computer. The design goals and features, the operation of the system and the preliminary performance of the prototype are described. The testing results show that the design goals of the prototype system have been achieved.  相似文献   
5.
As the nearest celestial body to the earth, the moon has become a hot spot again in astronomy field recently. The element analysis is a much important subject in many lunar projects. Remote X-ray spectrometry plays an important role in the geochemical exploration of the solar bodies. Because of the quasi-vacuum atmosphere on the moon, which has no absorption of X-ray, the X-ray fluorescence analysis is an effective way to determine the elemental abundance of lunar surface. The CE-1 X-ray fluorescence spectrometer (CE-1/XFS) aims to map the major elemental compositions on the lunar surface. This paper describes a method for quantitative analysis of elemental compositions. A series of ground base experiments are done to examine the capability of XFS. The obtained results, which show a reasonable agreement with the certified values at a 30% uncertainty level for major elements, are presented.  相似文献   
6.
正1.引言我们通常把波长很短,介于0.01~100埃(能量0.1ke V~1Me V)之间的电磁辐射,称为X射线。在整个X射线波段里,根据探测方法的不同,我们又模糊的分成了低能X射线(能量0.1~10ke V),中能X射线(能量5~70ke V),高能X射线(能量20ke V~1Me V)。三个能段没有明显的界限,彼此相互搭接在一起。探测X射线波段的探测器,即为X射线探测器。根据三个能段的特点,其相应的X射线探测器多采用  相似文献   
7.
Anode floating voltage is predicted and investigated for silicon drift detectors (SDDs) with an active area of 5 mm2 fabricated by a double-side parallel technology. It is demonstrated that the anode floating voltage increases with the increasing inner ring voltage, and is almost unchanged with the external ring voltage. The anode floating voltage will not be affected by the back electrode biased voltage until it reaches the full-depleted voltage (-50 V) of the SDD. Theoretical analysis and experimental results show that the anode floating voltage is equal to the sum of the inner ring voltage and the built-in potential between the p+ inner ring and the n+ anode. A fast checking method before detector encapsulation is proposed by employing the anode floating voltage along with checking the leakage current, potential distribution and drift properties.  相似文献   
8.
在领头阶和αs 修正阶,用QCD因子化方法,并对它的软胶子效应用光锥QCD求和规则分析D+→K0K+衰变过程,我们分析发现朴素因子化方法的结果远离实验结果,QCD因子化方法结果靠近实验结果,但是,在QCD因子化方法中,若考虑软胶子效应,其结果与实验结果相一致.另外,计算发现,软胶子效应在该衰变道中有相当大的贡献,因此不能被忽略  相似文献   
9.
A high resolution solar soft X-ray spectrometer (SOX) payload onboard a satellite is developed. A silicon drift detector (SDD) is adopted as the detector of the SOX spectrometer. The spectrometer consists of the detectors and their readout electronics, a data acquisition unit and a payload data handling unit. A ground test system is also developed to test SOX. The test results show that the design goals of the spectrometer system have been achieved.  相似文献   
10.
单载流子光电探测器的高速及高饱和功率的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
利用载流子漂移-扩散模型, 模拟并分析了InGaAs/InP单载流子光电探测器(Uni-traveling-carrier/UTC-PD) 在不同条件下的物理特性及其带宽和饱和特性, 结合器件实验结果分析了影响器件高速和高饱和性能的物理机理. 结论表明在吸收区采用浓度渐变掺杂和增加InP崖层(cliff layer), 可以显著提升器件饱和特性, 高入射功率下吸收区电场崩塌是器件饱和的直接因素, 直径大于20 μm的UTC探测器中RC常数仍是影响带宽的主要因素. 论文指出了优化器件结构、 提升器件性能的有效方法.  相似文献   
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