基于DSP系统的多道脉冲幅度分析器设计

介绍了一种基于DSP系统的高性能、低功耗多道脉冲幅度分析器的软硬件设计.硬件设计从提高多道脉冲幅度分析器的数据处理能力和降低系统功耗的角度出发重点介绍了能处理小信号的峰保电路、高速高精度的模数转换电路以及DSP系统及其相关外设接口;软件设计介绍了基于DSP系统的软件模块和基于CPLD的软件编程.还给出了该系统在XR-100CR探测器上测得的Fe的能谱示倒.     

几种核物理探测器在高压离子交换分离镅、锔流程流线分析中的应用

本文介绍一种超钚元素工艺流程流线监测系统。采用了Ge(Li)γ射线探测器,(艹氐)晶体n-γ分辨快中子探测器和Nal(Tl)薄晶体低能γ射线探测器,测定取样导管(引出于工作箱外)中料液的放射性。该系统已用于高压阳离子交换分离镅、锔的热实验中,为放化操作人员提供控制流程所需参数,文中扼要描述了取样盒、屏蔽体结构,各探测器的设计与调试,电子仪器和主要实验结果;并描述了Si(Au)面垒α流线监测器的设计、调试和条件实验结果。     

基于双闪烁体探测器的四路低本底αβ测量仪研制

介绍了一种基于双闪烁探测器的低本底αβ测量仪,该仪器可用于低水平αβ样品测量,并可区分αβ粒子。阐述了αβ双闪烁体探测器的主要参数和先进的数字化电路设计思路,给出了仪器αβ本底水平、串道比、αβ效率等物理性能的测试指标。描述了仪器软件自动坪曲线测量、自动刻度等功能的设计。     

Peakfit软件在LaCl_3γ谱解析中的应用

LaCl3探测器是一种能量分辨率优于NaI探测器的无机闪烁体探测器,在便携式核材料同位素识别等领域有广阔的应用前景。但是由于LaCl3探测器的能量分辨率仍低于HPGe探测器,在同位素识别过程中,产生的γ能谱经常会有峰重叠现象。然而目前没有合适的LaCl3γ谱解谱软件,所以尝试利用Peakfit软件来解析复杂的γ谱。以对LaCl3探测器效率刻度为例,研究Peakfit在γ谱解析中的应用,采用两种刻度方法同时进行比较,并用MCNP模拟验证。结果表明,利用Peakfit软件分析γ谱是可行的,也可以借鉴Peakfit软件中高斯拟合模块来编写多道软件。     

乳腺X射线基准装置能谱研究

介绍了乳腺X射线基准装置及其辐射野特性。根据钼靶X射线光机的各项参数,建立了蒙卡模拟的模型,使用蒙特卡罗软件模拟了光机的能谱。介绍了用于低能光子能谱测量的硅漂移探测器(SDD),并使用三种放射源对探测器进行了能量刻度,得到了能量与道址的线性关系。使用刻度好的硅漂移探测器进行了乳腺X射线基准能谱测量实验,测得了四个不同管电压下基准装置的能谱,实验结果与理论模拟结果吻合。     

用于正电子湮没寿命谱仪的探测器

一种用于正电子湮没寿命谱仪的探测器，该正电子湮没寿命谱仪包括起始道探测器和停止道探测器，与常规的正电子寿命谱仪起始道与停止道采用相同的探测器不同，本探测器采用了与起始道探测器不同的停止道探测器，在停止道探测器的闪烁体中央，有一圆形井，放置测量样品与22^Na正电子放射源。     

轻便型X荧光仪多道脉冲幅度分析器的研制

本文详细介绍了一种用于现场辐射测量的多道脉冲幅度分析器，多道分析器的道数为２０４８道，适合半导体探测器等具有高分辨能力的探测器使用，电路设计中选用了功耗较低的元器件，仪器适合野外使用。     

基于点源~(133)Ba刻度~(131)I探测效率的面积加权法

介绍了利用~(133)Ba点源的γ能峰(与~(131)I的γ能量相近)通过面积加权法对NaI(Tl)探测器模拟刻度碘盒中的~(131)I探测效率的原理和方法.其模拟刻度结果与标准刻度方法效率(~(133)Ba和~(131)I碘盒标准源刻度探测效率)进行了比较,其相对误差分别为7.15%和1.34%.研究表明,~(133)Ba点源面积加权法刻度NaI(Tl)探测器对碘盒中的~(131)I探测效率是一种简便而可靠的方法.     

基于DSP的数字多道脉冲幅度分析器设计

介绍了基于DSP的数字脉冲幅度分析器的设计.采用TMS320F2812作为数字核信号处理器,将ADC采集到的核信号进行数字积分、寻峰、阈值判别等数字处理,并得到能谱.系统通过USB接口实现数字多道与PC端监控及能谱分析软件的通信.最后本文给出了由NaI(TI)探测器得到的核信号经数字多道处理后,获得137Cs的能谱图.     

基于wxWidgets的闪烁晶体阵列探测器数据获取软件设计

介绍了一种用于闪烁晶体阵列探测器读出电子学的数据获取与分析读出软件。软件基于wx Widgets平台开发,采用了模块化设计,上位机通过USB总线与电子学硬件部分通信。软件系统包括命令行接口模块、数据采集模块、参数测量模块、时间和幅度校准模块以及实时显示模块。将软件应用于闪烁晶体阵列探测器系统的调试与测试,结果表明:软件可方便地应用于其它探测器前端电子学的读出系统中,具有广泛的应用前景。     

位置灵敏探测器的数据获取和处理系统的研制

本文介绍微通道板位置灵敏探测器的数据获取和处理系统的研制，简要描述了它的硬件结构和系统软件，本系统设计成一个ＮＩＭ标准单宽仪器插件，采用ＩＢＭ－ＰＣ／ＡＴ微型计算机作为实验数据读出及数据处理。具有实用、可靠和性能价格比高等特点。     

新型~(210)Po测量仪的研制

为提高~(210)Po测量仪的检测灵敏度、扩大活度检测范围和提升检测工效,研制了新型仪器。该仪器共有五个测量通道及其独特结构,探测元件选用面垒半导体探测器,屏蔽盒和送样器选择放射性杂质极少的黄铜等材料及结构,主要电路采用ARM微处器理和超高速运算放大器芯片,人机界面采用触摸技术与电脑程控相结合。仪器省去了铅室屏蔽装置、反符合探测器及其相关线路,重量轻、体积小。适用于~(210)Po样品分析,也可检测其他极微弱α样品。     

用于BELLE系统的FASTBUS软件包

本文介绍了一个作者设计和实现的将用地高能物理大型探测系统的数据采集系统的ＦＡＳＴＢＵＳ基本软件包。     

DAQ software architecture for Aleph, a large HEP experiment

The Aleph experiment has over 700000 electronics channels and is expected to generate over 500 Mbytes of data per second. The data acquisition system (DAQ) has been designed to process information from different parts of the detector in parallel using a large number of processing elements. The authors describe the architecture of the software used to implement the readout functions and to configure the system for data acquisition. The software environment, data-flow architecture, control-flow architecture, FASTBUS management, Aleph resource manager, and Aleph partition manager are discussed     

High-Speed FPGA-Based Pulse-Height Analyzer for High Resolution X-Ray Spectroscopy

A complete four channel acquisition system for high-resolution spectroscopy has been designed and realized. The analog section is composed of four semi-Gaussian shaping amplifiers with two software-selectable shaping times. The shaping times (150 and 450 ns) were chosen to perform either high rate or best resolution XRF measurements with state-of-the-art multielement silicon drift detector. The pulses' amplitudes are caught by four large-bandwidth peak-stretchers whose outputs are multiplexed into a single 10 MHz 12-bit analog-to-digital converter (ADC). A field-programmable gate array (FPGA) operating at 24 MHz (or 48 MHz) clock frequency controls the whole process and stores the four spectra in the on-chip RAM, thus guaranteeing a maximum counting rate per bin of 332 kcps and an overall counting rate in excess of 4 Mcps. The system interfaces the host PC by means of the enhanced parallel port with a custom made control software for data visualization and analysis as in a conventional MCA system. If more than four channels have to be managed, various boards can be operated in parallel on the same EPP bus.     

An on-line fuel management method using in-core detector readings for CANDU reactors

An on-line fuel management method for a CANDU reactor has been developed. In the method, the in-core detector readings are used for channel power generation for refueling channel selection. The in-core detector readings are converted to measured mesh readings, and the Kalman filtering technique is applied to reduce calculation and measurement errors of the mesh readings. Then, the estimated channel powers are fed into the refueling channel selection process, in which the channels are refueled so that the difference of zone power from the reference one is minimized. The performance of the method has been demonstrated against the operating data of CANDU 6 reactor. Also, it is found that the core tracking fuel management could be implemented, so that the proposed method would contribute to economic and safe operation of the reactor.     

Optimization of measurement distance of (109)~Cd K XRF system for obese subjects

The precision of results obtained from the 109Cd K XRF in vivo measurement system of bone lead for obese subjects with high BMI (body mass index) was poor. The main factor affecting the precision was the distance between tibia and detector. Compared with the standard phantom, a large phantom was used to simulate the obese subject in the measurements at different distances to the detector. The counts of Compton scattering increased highly because of the tissue overlying and surrounding tibia of the obese subject. When the distance between leg and detector was too small, the instrument would produce the distorted X-ray spectra, so that the obtained data were inaccurate. In order to ensure good measurement precision and accuracy, the distance between leg and detector should be maintained at 25 mm during the counting period. Meanwhile, the dead time displayed instantly on the instrument should be controlled to around 30%.     

数字化核测装置的研究

介绍了以单片机AT89C52为核心的反应堆数字化核测装置的设计方法,同时也给出了该仪表系统的硬件结构和软件框架.本核测仪表在测量低端电流的时候,应用了DDC112芯片.在设计这套仪表系统的时候,充分考虑了软硬件抗干扰措施.     

KZ-D02F型电离室α测氡仪的研制

介绍了一种新型测氡仪,该仪器采用电离室作为探测器,可在动态和静态两种不同的模式下工作,具有参数设置,时钟设置,数据实时显示、存储、查询以及上传等功能。     

基于LPC932的低功耗计数电路的设计

介绍一种低功耗实时脉冲计数电路。该仪器基于LPC932单片微机为核心微处理器,来完成数据采集、处理,存储,实时时钟控制,液晶显示,通信等功能。针对便携式仪器的低功耗特性要求,从硬件电路和软件编程两方面对整个系统进行了低功耗设计。