用于硅多条阵列探测器的48路前置电荷灵敏放大器的研制

介绍了一套用于硅多条阵列探测器中的高密度多通道电荷灵敏放大器的研制和阵列探测器电子学的发展现状和工作原理,提出了设计原则和设计思路,特别介绍了一个新开发的用于硅多条探测器中的48路电荷灵敏前置放大器的设计和实际测量结果.它具有低成本、高密度的特点,好于1%的能量分辨和良好的长期稳定性.     

用于辐射成像探测器的集成前置放大器电路

介绍了辐射成像探测器陈列的电流积分型前置放大器。并推荐３种用于辐射成像陈列探测器的集成前置放大器阵列电路，ＨＸ２、ＭＸ３和、ＭＸ４，前者为１６路阵列，后两种为１２８路阵列。     

多路电荷灵敏前置放大器

介绍了一种多路电荷灵敏前置放大器,其路数最多为8路,它有功耗低,体积小,价格低廉,使用方便等特点,并对它的设计以及特点作了较详细的阐述.     

金硅面垒型半导体探测器在α能谱测量中的应用研究

针对α能谱测量需要探测器能量分辨率高、性能稳定及探测效率高等要求,选用金硅面垒型半导体探测器进行α能谱测量.论述了金硅面探测器的主要性能指标及影响因素,同时针对探测器输出信号的特点以及α能谱测量要求,从理论上分析了前置放大器的类型及设计时需要注意的事项,并设计了一种实用低噪声电荷灵敏前置放大器.实测α能谱数据表明,性能满足α能谱测量要求.     

基于多路电荷灵敏前置放大器构建多路剂量测量系统

针对多路空气电离室剂量探测器输出信号的特点和测量需求,利用一种多路电荷灵敏积分型前置放大器专用器件(ASIC),实现了1 024路空气电离室剂量探测器的微小电流信号的同步放大、处理和采集。在6 MV(30 MU/min)医用加速器下,进行了实验测试,10 ms积分时间内,电荷量约为0.15 p C,测量灵敏度约为3 n C/Gy。结果表明,利用该种前置放大器构建的测量系统,其量程和积分时间等参数满足测量需要,可在该剂量测量系统中应用。     

硅多条探测器性能测试

介绍了对一种由近代物理研究所和北京大学联合研制的硅多条探测器性能测试的结果。具体测试内容包括：探测器的能量分辨率、Al面厚度以及探测器各条间的cross-talk(相互影响)。同时,也对进口的Canberra有确定标称的硅多条探测器做了类似的测试,并进行了性能对比。     

空间X射线测量用电荷灵敏前置放大器和主放大器的研制

为配合我室与高能物理研究所合作的星载“多路Si—PIN探测器系统”地面原理样机项目的需要，开发研制空间X射线测量用多路电荷灵敏前置放大器和主放大器。把电荷灵敏前置放大器和主放大器共同安放在1个90mm×60mm的电路板上，有单独的3路输入和输出，相当于常规的3个电荷灵敏前置放大器和主放大器。整个电路采用低功耗的表面贴元器件，具有低噪声、低功耗、电路简单、体积小等特点，并可应用于多路探测器测量系统中。     

二维阵列电离室探测器数据采集系统设计

介绍了用于对肿瘤放射治疗进行剂量验证的二维阵列电离室探测器的数据采集系统的设计与开发。文章描述了该二维阵列电离室探测器系统的构成以及工作原理,重点讨论了该探测器的数据采集子系统的设计过程,并完成了由前置放大器、前放控制器、数据采集控制器构成的数据采集子系统的开发。用户端可通过TCP/IP方式对探测器系统的参数进行设置,并进行数据高速采集、获取和进一步的处理。     

高灵敏大面积硅PIN探测器阵列

提出了一种效率增强型硅ＰＩＮ探测器和新型高灵敏大面积硅ＰＩＮ探测器阵列的设计思想，并且对它们的探测灵敏度和相对误差进行了详细的理论模拟计算。从理论研究结果可以得到：效率增强型硅ＰＩＮ探测器可以显著提高对γ射线的探测灵敏度；高灵敏大面积硅ＰＩＮ探测器阵列相对于单个效率增强型硅ＰＩＮ探测器具有更高的探测灵敏度。结合脉冲放大器，可用于探测极注量的γ射性。     

一种简易实用的三管电荷灵敏放大器

设计了一种简易实用的3管电荷灵敏放大器,其使用器件少,调试简单,具有较好的信噪比,适用于离子注入式半导体探测器、金硅面垒半导体探测器的前置放大。     

Imaging of radiation detectors properties by IBIC

Ion Beam Induced Charge (IBIC) technique was used for imaging different properties of several radiation detectors. Small lateral dispersion of 3–5 MeV proton microbeam allowed us to investigate a scanned detector as an array of independent charge sensitive detectors. The detector response function at each point was separately analyzed. The mean and the median detected proton energy, as well as standard deviation, was calculated and connected to the local value of the detector collection efficiency and resolution. The progressive change (increase or decrease) of the collection efficiency with the time was studied. IBIC was also applied for imaging the incomplete charge collection layer in Si(Li) X-ray detectors.     

Performance Characteristics of BGO Detectors for a Low Cost Preclinical PET Scanner

PETbox is a low-cost benchtop PET scanner dedicated to high throughput preclinical imaging that is currently under development at our institute. This paper presents the design and characterization of the detectors that are used in the PETbox system. In this work, bismuth germanate scintillator was used for the detector, taking advantage of its high stopping power, high photoelectric event fraction, lack of intrinsic background radiation and low cost. The detector block was segmented into a pixelated array consisting of 20 × 44 elements, with a crystal pitch of 2.2 mm and a crystal cross section of 2 mm × 2 mm. The effective area of the array was 44 mm × 96.8 mm. The array was coupled to two Hamamatsu H8500 position sensitive photomultiplier tubes, forming a flat-panel type detector head with a sensitive area large enough to cover the whole body of a typical laboratory mouse. Two such detector heads were constructed and their performance was characterized. For one detector head, the energy resolution ranged from 16.1% to 38.5% full width at half maximum (FWHM), with a mean of 20.1%; for the other detector head, the energy resolution ranged from 15.5% to 42.7% FWHM, with a mean of 19.6%. The intrinsic spatial resolution was measured to range from 1.55 mm to 2.39 mm FWHM along the detector short axis and from 1.48 mm to 2.33 mm FWHM along the detector long axis, with an average of 1.78 mm. Coincidence timing resolution for the detector pair was measured to be 4.1 ns FWHM. These measurement results show that the detectors are suitable for our specific application.     

Cylindrical Silicon-on-Insulator Microdosimeter: Design, Fabrication and TCAD Modeling

A novel silicon-on-insulator (SOI) microdosimeter has been designed and fabricated using planar processing techniques to realise a device with a micron-scale well-defined sensitive volume. Cylindrical structures were employed to allow for an improved definition of the average chord length of the sensitive volume over that of previous elongated parallelepiped solid-state detector designs. The structures were manufactured on individual silicon mesas situated on top of a buried oxide insulating layer. The mesa design eliminated lateral charge diffusion. Two kinds of test structures were designed with sensitive region widths of 2 mum and 10 mum. In addition, an array of 900 cylindrical diodes was fabricated to increase the charge collection statistics. TCAD (Technology Computer Aided Design) modeling of the electrostatic potential and electric field profile of the cylindrical microdosimeter was carried out to obtain 3D potential and electric field profiles. The modeling revealed a radial electric field within the cylindrical-shaped sensitive volume with a 1/r dependence. While the electric field at the core of the cylindrical microdosimeter was not sufficiently high to induce avalanche signal multiplication, the higher electric field at the core should still assist in the measurement of low linear-energy transfer (LET) events.     

基于3D Si PIN阵列热中子探测器的变增益宽动态前端读出电子学设计

基于Si CMOS技术的前端读出ASIC主要是根据3D Si PIN阵列热中子探测器的输出信号特性设计的。所设计的读出ASIC的主要电路模块包括电荷灵敏放大器（CSA）、模拟开关设计、具有三级电荷灵敏自动转换的自动增益控制模块（AGC）、相关双采样（CDS）和基准电流源电路。仿真结果表明,前端电路的输入动态范围为10 fC~80 pC。根据热中子探测器输出信号特性设计的ASIC的3个增益系数分别为19 V/pC、039 V/pC和94 mV/pC。所设计的ASIC的积分非线性小于 1%。单通道静态功耗约为 536 mW。零输入探测器电容时的等效噪声电荷为2416e-。计数率可达1 MHz 。     

A digitalizing board for the prototype array of LHAASO WCDA

In this paper,a digitalizing board for readout of PMT signals in the prototype array of WCDA(water Cerenkov detector array)for LHAASO(Large high altitude air shower observatory)is designed.The prototype array is composed of 9 PMTs,including the pulse time and charge measurement from the PMTs,and clock generation and trigger decision.In the digitalizing board,FPGA reconfiguration and data readout via VME bus are implemented.Test results show that the performances meet well with the requirements of readout electronics.It has been installed in Yangbajing and tests with the prototype array and DAQ is ongoing.     

晶体表面特性对PET探测器性能的影响

<正>电子发射断层成像(Positron Emission Tomography,PET)作为最灵敏和具有定量测量能力的功能分子影像技术,越来越广泛地应用于生物医学研究,如疾病的动物模型、新药物的研发和新治疗方法的评估等。提高探测器的性能是改进PET仪器性能的关键,PET探测器通常由分割的闪烁晶体阵列和光探测器组成,文中使用位置灵敏光电倍增管和不同晶体表面特性的硅酸钇镥((Lu,Y)2Si O5,LYSO)晶体阵列,对新型的双端读出三维PET探测器和传统的单端读出二维PET探测器的性能进行了测量。实验结果表明,对于双端读出PET探测器,两种晶体阵列提供相近的晶体分辨图和能量分辨率,但非抛光晶体阵列提供好的深度分辨率,双端读出PET探测器需要使用表面不抛光的晶体阵列;对单端读出PET探测器,抛光晶体阵列提供好的晶体分布图和能量分辨率,单端读出PET探测器需要使用表面抛光的晶体阵列。     

远距离大动态范围电荷测量电路的设计

介绍了大型高海拔空气簇射观测站(Large High Altitude Air Shower Observatory,LHAASO)空气簇射芯探测器阵列(Shower core detector array,SCDA)读出电子学方案的预研设计。系统采用基于电荷积分法的电荷测量方案,读出电子学通过同轴电缆接收光电倍增管输出的电流信号;采用在输入端与电荷积分放大器的虚地点之间接入等效50?电阻的终端阻抗匹配方案,并通过Pspice仿真验证该阻抗匹配的可行性。电路测试结果表明,该电路能满足远距离10 bit大动态范围电荷测量的设计指标要求。     

基于GAGG:Ce晶体耦合SiPM的位置灵敏探测器的设计与评估

为满足当前γ相机对高分辨率、低成本、小型化探测器的需求，提出了采用硅光电倍增管（SiPM）耦合GAGG:Ce晶体阵列的方式代替传统的位置灵敏型光电倍增管（PSPMT）耦合晶体阵列的方式以构成新型γ相机探测器，并设计了均匀电荷分配电路（SCDC）和阻抗电桥电路作为探测器的读出电路，同时设计了前沿定时电路作为数据采集触发电路。实验结果表明：当温度为25 ℃、探测器供电电压为28.5 V时，该探测器在511 keV射线的激发下，散点图的峰谷比高达3.84，对511 keV和662 keV射线的平均能量分辨率分别为10.63%和9.71%，具有较好的分辨性能。     

CMOS工艺X射线图像传感器设计

本文设计了一种不需闪烁体或增感屏,直接对X射线进行探测成像的线阵图像传感器,对其电荷收集进行了理论分析,设计了辐射加固的光敏元结构。采用0.5 μm DPTM CMOS工艺,针对单个像元内含不同个数光敏元的结构进行了流片和X射线实验测试。测试结果表明：该图像传感器暗信号电压约为1 V,随像元内光敏元个数的增加暗信号电压增大;饱和输出电压为2.4 V;随光敏元个数的增加,电荷收集总量增加,总寄生电容也同时增加,所设计的单个像元含3个光敏元的结构能得到相对更大的有效输出电压。