基于PIN光电二极管的个人辐射探测器研制

为使公众能自行探测所处环境的辐射水平,本文利用PIN光电二极管直接测量X/γ射线的原理研制了便携式环境辐射探测系统,该系统采用智能终端控制探测设备。其中,探测模块中设计了弱信号放大电路,控制和通信模块的设计基于无线微控制器。该环境辐射探测器具有低成本、低功耗、体积小、易使用、易组网等特点。经国防科技工业电离辐射一级计量站检定,探测器各项指标均符合国家剂量仪鉴定规程JJG 521-2006的要求。     

光电二极管在辐射探测系统中的线性应用研究

针对光电二极管电压型放大器在辐射探测系统引起的非线性响应,分析并验证了光电二极管电压放大器在稳定辐射探测中,主要因响应度受到调制而出现响应非线性;在脉冲辐射探测中,影响系统线性度的是电压放大器中的带宽调制现象;提出了将带有电压跟随器的互阻放大器作为各种辐射探测的解决方案;阐明了从线性度考虑出发,用光电二极管互阻放大器代替电压式放大器的合理性。     

半导体探测器在秦山第二核电厂辐射监测系统上的应用

对在秦山第二核电厂辐射监测系统中使用的两种半导体探测器PIPS（Planar Implanted Passivated Silicon）和SIR的原理、结构、三种应用方式、使用情况进行了介绍和初步研究。     

用于HL-2A装置的新型硬X射线探测器

介绍了一种应用于托卡马克等离子诊断领域的新型硬X射线探测器,该探测器主要由硅酸钇镥(Lutetium-yttrium Oxyorthosilicate,LYSO)闪烁体和硅光电倍增管(Silicon Photomultiplier,Si PM)组成。基于项目应用需求,对探测器的选型和基于粒子输运蒙特卡罗仿真软件GEANT4的探测器设计加以阐述,并搭建了前端的探测系统,在HL-2A托卡马克装置上进行了现场诊断实验。实现了硬X射线空间能谱和辐射强度分布的诊断测量。实验表明该探测器阵列具有10 ms的时间分辨率,同时具有结构紧凑、使用方便等特点,能够满足等离子体诊断中硬X射线动态能谱和强度分布测量的诊断需求。     

硅光电倍增器在剂量测量中的应用现状与前景

本文介绍了最近发展的新型硅光电倍增器(SiPM)在剂量测量中的应用现状和前景,分析了其暗计数率高(室温下0.1~10 MHz/mm~2)、对温度敏感、动态范围有限(通常只有2~3个量级)等问题。基于体积小、工作电压低、对磁场不敏感、增益高等特点,硅光电倍增器很适合代替传统的光电倍增管用于便携式剂量仪表。目前,利用脉冲幅度甄别、温度漂移实时修正的方法,可以有效地降低暗计数率高、温度敏感性的影响;但是,即便采用了符合测量、组合探测器等方法,测量范围仍然是限制SiPM在剂量测量应用的主要问题。     

大体积CsI-SiPINγ计数探测器系统的研制

2008年度完成了探测器制备工艺的改进,研制了50、100mm。全耗尽SiPIN光电二极管样品。从漏电流测量结果看,探测器在全耗尽电压100V时,漏电流为8．9nA,可满足要求。对新研制的100衄n2全耗尽SiPIN光电二极管与不同形状的CsI晶体进行了光学耦合。对封装好的CsI—SiPINγ探测器进行了对137Cs661keVγ射线的能谱响应测量,同时测量了本底噪声谱,得到了能量下限为170keV。     

硅二极管阵列探测器在田湾核电站的应用

田湾核电站一期工程辐射监测系统中,大量使用了硅二极管阵列探测器。论文介绍了硅二极管阵列探测器的架构、原理、应用方式和保护逻辑。对运行期间出现的问题,进行了研究和探索,给出了可行的解决方案。     

二维三氧化钨纳米结构的合成及其在光电探测器中的应用

三氧化钨（WO₃）是制造晶体管和光电探测器的理想材料,虽然在WO₃纳米结构的生长方面已经完成了一些工作,但是制造足够长的理想型纳米线仍然是一个挑战。在众多的合成方法中,作者选择了化学气相沉积（CVD）方法合成WO₃纳米线,并对其在光电传感器中的应用进行了研究。影响WO₃纳米线成品率的主要因素是前体材料温度、基片位置、载气流速和生长持续时间。在合适的生长条件下生长的纳米线长度最长约为100 μm。这些WO₃纳米线可用来制造高性能的光电探测器,WO₃光电探测器具有灵敏度高、响应速度快、模块微型化等优良的器件性能,表明二维WO₃纳米线在光电探测器的制造中具有很大的优势。      

闪烁体探测器在田湾核电站辐射监测系统中的应用

以GLM201 -1液体γ活度监测仪为代表介绍了闪烁体探测器在田湾核电站辐射监测系统中的应用并对该仪器的结构、原理、使用情况进行了初步研究.     

裂变室探测器在高温气冷堆核电站示范工程核测量系统中的应用

高温气冷堆核电站示范工程是我国中长期发展规划中的重大专项之一,也是我国第一座拥有自主知识产权的核电站。文章介绍了高温气冷堆核电站核测量系统的工作原理和系统组成,剖析了裂变室中子探测器的特点及其在核测量系统中的应用。裂变式探测器所具有的γ信号甄别能力强、中子通量测量范围宽等优点,应用于高温气冷堆核测量系统,可以满足大空间、宽范围的堆外中子通量测量需求,有利于简化系统组成、提高经济性。与其他压水堆核电站的核测量系统相比较,应用裂变室中子探测器具有一定的优越性。     

AXUV探测器标定及受辐照响应衰减研究

在EAST和HT-7装置上,具有宽能谱响应的AXUV光电二极管探测器主要用于辐射功率的绝对测量。探测器在经历多轮等离子体放电中的累积辐照效应后,观察到其表面发生变化。为了解探测器响应衰减程度,设计了相对标定实验,分别采用标准可见光光源和软X射线管作为标定光源,对EAST和HT-7实验中经历过不同放电次数的5个探测器进行了标定。标定结果表明,AXUV探测器在经历了EAST上约25 000次的等离子体放电累积辐照后,其在软X射线能段的响应下降约15%。而探测器在可见光能段的辐照损伤效应主要表现为同一个探测器不同通道之间对可见光响应的不一致性加剧。结合探测器在等离子体放电辐射场中的几何参数,对探测器受到的累积辐照剂量进行了估算。     

Influence of impurity seeding on the plasma radiation in the EAST tokamak

Plasma radiation characteristics in EAST argon(Ar) gas and neon(Ne) gas seeding experiments are studied.The radiation profiles reconstructed from the fast bolometer measurement data by tomography method are compared with the ones got from the simulation program based on corona model.And the simulation results coincide roughly with the experimental data.For Ar seeding discharges,the substantial enhanced radiations can be generally observed in the edge areas at normalized radius ρ_(pol)~0.7–0.9,while the enhanced regions are more outer for Ne seeding discharges.The influence of seeded Ar gas on the core radiation is related to the injected position.In discharges with LSN divertor configuration,the Ar ions can permeate into the core region more easily when being injected from the opposite upper divertor ports.In USN divertor configuration,the W impurity sputtered from the upper divertor target plates are observed to be an important contributor to the increase of the core radiation no matter impurity seeding from any ports.The maximum radiated power fractions f_(rad)(P_(rad)/P_(heat)) about 60%–70% have been achieved in the recent EAST experimental campaign in 2015–2016.     

ICI探测器单位γ灵敏度研究

探测器灵敏度及其能量响应特性在探测器的设计和研制过程中占有十分重要的地位.从理论和实验两个方面研究了ICI探测器的γ灵敏度及其γ射线能量响应特性.在60 Co 1.25MeV γ辐射源装置上进行实验测量得到ICI探测器的单位γ灵敏度为1.8×10-20 (±5%)C·cm2 ,理论计算的单位γ灵敏度为1.78×10-20 C·cm2 (γ能量1.25MeV),理论和实验结果符合得较好.研究结果表明,入射γ射线能量在1～10MeV范围内变化时,ICI探测器具有平坦的γ灵敏度响应曲线.     

Response of Si p-i-n diode and Au/n-Si surface barrier detector to heavy ions

Pulse height versus energy calibrations of a Si p-i-n diode and a Au-/n-Si surface barrier detector have been studied for heavy ions with atomic number (Z₁) from 3 to 79 in a range from 0.1 to 0.8 MeV per nucleon as a function of bias voltage and detector tilting angle. The detector response is simultaneously measured using a time of flight-energy elastic recoil detection analysis set-up with recoils produced over a wide energy range from a thick target of each element. Prior to impinging on the Si detector, the individual recoil is tagged by its energy determined from the time of flight and tabulated isotopic mass. For both detectors, the pulse height-energy calibration for recoils with a given Z₁ is described well by a linear relationship with small systematic deviations. The linear-fit parameters show similar, but not identical dependence on both Z₁ and bias voltage (collecting field strength) for the surface barrier detectors and the p-i-n diode. These results suggest that the efficiency of electron–hole pair collection is markedly dependent on the different electric field configurations for the two detector structures.     

GaAs核辐射探测器研制的初步结果

介绍了厚度为300～800μm,有效面积为50-113mm^2的高阻GaAs单晶材料制备的核辐射GaAs探测器的研制工艺,测试结果。     

Sensitivity of a new-developed neutron detector

We develop a kind of neutron detector, which consists of a polyethylene thin film and two PIN semiconductors connected face-to-face. The detector is insensitive to γ-rays. Its sensitivity to neutron has been calculated with MCNP program and calibrated by experiments, and the results indicate that the neutron sensitivity of the compensation detector will vary with polyethylene convel‘ter. The compensation PIN detector can be employed to measure pulse neutron in neutron and gamma mixture radiation field.     

一种新型半导体探测器的应用

介绍了一种测量X射线的Si-PIN电制冷半导体探测器,以及它在X射线谱分析中的应用。由于该探测器采用了电制冷方法,从而摆脱了传统的Si(Li)探测器在使用和保存时必须定期向其添加液氮的麻烦。     

Effect of metal electrode on characteristics of gamma-irradiated silicon carbide detector

Silicon carbide (SiC) is a highly promising semiconductor neutron-detector material for harsh environments such as nuclear reactor cores and spent-fuel storage pools. In the present study, three 4H–SiC p–i–n diode detectors were fabricated as variations of those metal-electrode structures. The I–V characteristics and alpha-particle responses of the detectors were measured before and after gamma-ray exposure. The detector with a Ti/Au electrode showed the lowest change of leakage current after irradiation; none of the detectors showed any change in the charge-collection efficiency when a sufficient electric field was applied after gamma irradiation of up to 8.1 MGy.     

Si-PIN探测器中子直照灵敏度研究

介绍了利用K600中子发生器进行Si-PIN探测器灵敏度标定的实验方法,并在实验中测出了Si-PIN探测器对14MeV中子的直照灵敏度。同时,利用MCNP模拟程序对Si-PIN探测器不同能量的中子直照灵敏度进行了理论计算,实验灵敏度处理结果和理论计算值较为一致。     

Application of CMOS charge-sensitive preamplifier in triple-GEM detector

1 Introduction With novel materials and advanced technique of printed circuit board (PCB) and micro-electronics be- ing used in MPGD, over the past two decades, great progress has been made in MPGD[1], and as a new type of MPGD, the GEM[2] detector was developed during the late 1990s. Standard GEM from CERN is a thin, two-side copper-coated Kapton foil, perforated with a high density of holes etched using a photolitho- graphic process. The diameter of these holes is about 70 μm (ext…