共查询到19条相似文献,搜索用时 203 毫秒
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《中国新技术新产品》2020,(2)
该文利用蒙特卡罗程序包Geant4构建了高纯锗探测器的实际结构,模拟了γ射线在高纯锗探测器中与材料发生的相互作用。通过统计光子在高纯锗探测器中的能量沉积,累计得到4种能量射线的能谱,并通过拟合公式对能谱进行展宽,模拟实际能谱。将模拟得到的能谱结果与高纯锗探测器探测到的实际能谱进行对比,比较模拟能谱和实际能谱的全能峰、统计效率和半峰宽,验证了分辨刻度系数在实际模拟中的可行性,为进一步进行高纯锗探测器的模拟实验提供了技术支持。 相似文献
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正目前,国内外生产的X射线荧光测厚仪性能主要取决于准直器和探测器,毛细管加上SDD硅漂移探测器是最好的结构组合,而且业内的毛细管荧光测厚仪也都全部使用SDD硅漂移探测器。这里选取了两台行业内知名的品牌进行比较,参与比较的机型1由4准直器和Si-PIN探测器组成,机型2由毛细管和SDD硅漂移探测器组成。一、测量范围测量样品1是标准厚度为0.046μm的Au薄片。 相似文献
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水体放射性自动监测站的高纯锗γ能谱连续监测系统的分析对象是动态的环境水样.使用蠕动泵模拟水体流动,通过实验测量高纯锗γ能谱对不同流速、不同浓度40K溶液的探测效率,实验的流速范围为0~10 L/min、40K活度浓度范围为10.4~520 Bq/L,测得效率未见显著变化,据此,可将标准溶液密封在测量容器中作静态测量效率... 相似文献
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在使用锗酸铋闪烁晶体γ射线探测器对γ射线能谱进行测量时,由于环境温度的变化,会引起探测器能量分辨率的变化和所测谱峰位的漂移。采用合适的方法对探测器进行冷却和保温,可以很好地解决由于温度变化给测量结果带来的误差问题。 相似文献
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单能X射线光源是由X射线光机、双晶单色器、标准探测器以及准直系统组成。X射线光机产生的连续X射线,通过与双晶单色器发生布拉格衍射完成单色化,调节不同的特定布拉格角度得到能量范围30~160keV的单能X射线。为了研究标定装置的能量展宽,需要对该装置产生的单能X射线的能量分辨率进行研究。结果表明Si(220)晶体产生的单能X射线的能量分辨率为0.91%@30keV和2.3%@70.6keV,Si(551)晶体为1.97%@80.1keV和3.45%@142.6keV。使用这套装置对溴化镧晶体探测器的能量响应进行校准验证,实验发现该装置的能量分辨率良好,可以应用在多种类型探测器的标定实验、X射线质量衰减系数测量以及多层膜反射率测量等领域。 相似文献
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衍射法X射线激光分束光栅平行度测量系统(英文) 总被引:2,自引:0,他引:2
介绍了软X射线光栅分束镜Mach-Zehnder干涉等离子体诊断系统调整用双频光栅线条平行度的衍射法测量系统.该系统主要由激光器,准直镜,待测光栅,精密转台(含角度测量仪),直线工作台,光栅调节架和探测器组成.分析了系统中各种误差对测量精度的影响其中包括距离测量误差、波长误差、光栅准直误差即光栅刻线与入射光和反射光组成的平面不垂直、光栅转动过程的误差、光栅表面面型误差、探测器误差,经计算得到系统的绝对误差为minute.计算表明,该系统的测量精度满足软X射线Mach-Zehnder干涉系统对双频调整光栅的性能要求. 相似文献
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卤化物钙钛矿由于具有高射线吸收系数、高载流子迁移率寿命乘积、可低温溶液法生长等特性,有望突破传统高纯锗和碲锌镉探测器在成本、芯片兼容性和大尺寸成像等方面的制约,成为新一代性能优异的室温射线探测材料。本文从卤化物钙钛矿材料的基本性质与射线探测原理出发,介绍了2015年以来卤化物钙钛矿射线探测材料与器件的发展历程;系统介绍了直接型射线探测器(强度、成像、能谱)及闪烁体探测器的最新研究成果;分析了材料特性与器件结构对射线探测器性能的影响机制,为今后更高效的卤化物钙钛矿射线探测器的开发提供参考。 相似文献
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为建立高注量率同步辐射X射线计量领域相关的国家标准,对同步辐射X射线能量标定方法进行研究。在北京同步辐射装置上选择6、10和20keV三个能量点进行实验,得到的传递探测器校准因子与辐射能量的关系曲线近似直线,变化趋势呈线性递减;在20keV能量点,不同直径光阑条件下进行的标定实验验证了传递探测器的校准因子与光源照射到基准电离室与传递探测器的光子通量有关。在上海光源上进行10~70keV能量标定实验,得到传递探测器的校准因子拟合曲线;10~20keV能量段的变化趋势与在北京同步辐射装置得到的校准因子变化趋势一致,30~70keV能量段的校准因子随着能量的增加而平稳缓慢增大。对各个能量点标定产生的A类不确定度进行评定,为后续建立国家计量标准同步辐射X射线空气比释动能量值传递体系提供了技术数据。 相似文献
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A.S. Hoover N. HotelingM.W. Rabin J.N. UllomD.A. Bennett P.J. KarpiusD.T. Vo W.B. DorieseG.C. Hilton R.D. HoranskyK.D. Irwin V. KotsuboD.W. Lee L.R. Vale 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):302-305
Microcalorimeter detectors provide unprecedented energy resolution for the measurement of X-rays and soft gamma-rays. Energy resolution in the 100 keV region can be up to an order of magnitude better than planar high-purity germanium (HPGe) detectors. The technology is well-suited to analysis of materials with complex spectra presenting closely spaced photopeaks. One application area is the measurement and assay of nuclear materials for safeguards and fuel cycle applications. In this paper, we discuss the operation and performance of a 256-pixel array, and present results of a head-to-head comparison of isotopic determination measurements with high-purity germanium using a plutonium standard. We show that the uncertainty of a single measurement is smaller for the microcalorimeter data compared to the HPGe data when photopeak areas are equal. We identify several key areas where analysis codes can be optimized that will likely lead to improvement in the microcalorimeter performance. 相似文献
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(HP)Ge Measurement of spectra for diagnostic X-ray beams 总被引:1,自引:0,他引:1
The X-ray spectra applied in diagnostic radiology to the energy range between 50 and 125 kVp, were experimentally determined using a high-purity germanium detector, (HP)Ge, coupled to a multichannel analyser. A simple stripping procedure was implemented, according to that described by Seelentag and Panzer, to correct the pulse height distribution and then to determine the photon spectra. The measurements were performed for those conditions where the X-ray beam is transmitted through Pb filters 0.2-0.7 mm thick. It was necessary to estimate the effective dose in the same way that it is done for radiology diagnosis room shielding projects. The spectra were also determined to the X-ray qualities recommended by the IEC for primary diagnostic X-ray and for X-ray beams attenuated by aluminium filters 2.5-42.5 mm thick. The spectra obtained were compared with data derived from the literature presenting good agreement. 相似文献
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CdTe探测器对单能平行光子源的绝对测量之前,需要进行效率刻度。利用MCNP5蒙特卡罗模拟程序建立CdTe探测器物理模型,模拟计算了10~260keV能量段能点的本征探测效率,在10~60keV能量段探测效率高于75%。用单能X射线装置和HPGe探测器对CdTe探测器本征探测效率进行了实验刻度。结果表明,在10~100keV能量范围内CdTe探测器的模拟效率与实验效率趋势一致,最大误差不超过5.6%。因为Te元素在27keV和32keV处会产生逃逸峰,导致探测效率在这2个能量处有明显下降趋势。用241Am和133Ba放射源对CdTe探测器进行效率刻度验证,在能量为59.54keV和81keV放射源标定的探测效率与单能X射线辐射装置测量值相符。 相似文献
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Fumiakira Mori Yasuhiro Minamikawa R. M. Thushara Damayanthi Steven Leman Nobuyuki Zen Masashi Ohno Hiroyuki Takahashi Hidenori Toyokawa Hajime Tanida Tomoya Uruga 《Journal of Low Temperature Physics》2008,151(1-2):150-154
Small-pixel TES is promising for imaging-spectroscopy applications. Researchers demand a high-spatial-resolution energy-resolving
detector for many kinds of applications. However the spatial resolution and the energy resolution are quite restricted in
the present semiconductor detector, so we are developing a new pixellated array based on the transition edge sensor (TES)
technology. In this measurement, we developed an Ir-TES array which consists of 9 small TESs and are voltage biased in parallel.
We performed measurements at SPring-8 with 6 keV X-rays and scanned the TES using a collimator by the two-dimensional scanning
method. Position dependency on pulse height and risetime has been analyzed in detail. 相似文献
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Patricia Mortreau Reinhard Berndt 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2005,550(3):675-690
The traditional method used to determine the Uranium enrichment by nondestructive analysis is based on the “enrichment meter principle” [1]. It involves measuring the intensity of the 186 keV net peak area of 235U in “quasi-infinite” samples. A prominent factor, which affects the peak intensity, is the presence of gamma absorbing material (e.g., container wall, detector cover) between the sample and the detector. Its effect is taken into consideration in a commonly called “wall thickness” correction factor. Often calculated on the basis of approximations, its performance is adequate for small attenuation factors applicable to the case of narrow beams. However these approximations do not lead to precise results when wide non-parallel beams are attenuated through thick container walls.
This paper is dedicated to the calculation by numerical integration of the geometrical correction factor (Kwtc) which describes the effective mean path length of the radiation through the absorbing layer. This factor was calculated as a function of various measurement parameters (types and dimensions of the detector, of the collimator and of the shielding) for the most commonly used collimator shapes and detectors. Both coherent scattering (Rayleigh) and incoherent scattering (Compton) are taken into account for the calculation of the radiation interaction within the detector. 相似文献
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Matthew David Wilson Robert CernikHenry Chen Conny HanssonKris Iniewski Lawrence L. JonesPaul Seller Matthew C. Veale 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):158-161
A new small pixel cadmium zinc telluride (CZT) detector has been developed for hard X-ray spectroscopy. The X-ray performance of four detectors is presented and the detectors are analysed in terms of the energy resolution of each pixel. The detectors were made from CZT crystals grown by the travelling heater method (THM) bonded to a 20×20 application specific integrated circuit (ASIC) and data acquisition (DAQ) system. The detectors had an array of 20×20 pixels on a 250 μm pitch, with each pixel gold-stud bonded to an energy resolving circuit in the ASIC. The DAQ system digitised the ASIC output with 14 bit resolution, performing offset corrections and data storage to disc in real time at up to 40,000 frames per second. The detector geometry and ASIC design was optimised for X-ray spectroscopy up to 150 keV and made use of the small pixel effect to preferentially measure the electron signal. A 241Am source was used to measure the spectroscopic performance and uniformity of the detectors. The average energy resolution (FWHM at 59.54 keV) of each pixel ranged from 1.09±0.46 to 1.50±0.57 keV across the four detectors. The detectors showed good spectral performance and uniform response over almost all pixels in the 20×20 array. A large area 80×80 pixel detector will be built that will utilise the scalable design of the ASIC and the large areas of monolithic spectroscopic grade THM grown CZT that are now available. The large area detector will have the same performance as that demonstrated here. 相似文献