IEC 61342-1995
核仪器 多脉冲幅度分析仪 主要特性、技术要求和试验方法

Nuclear instrumentation - Multichannel pulse height analyzers - Main characteristics, technical requirements and test methods

标准号

IEC 61342-1995

发布日期

1995年02月

实施日期

废止日期

无

中国标准分类号

F81

国际标准分类号

27.120.10

发布单位

国际电工委员会

适用范围

This International Standard is applicable to multichannel pulse height (amplitude) analyzers (MCA) with linear amplitude response, which are measuring devices used for acquisition, storage and processing of amplitude distributions. These analyzers automatically carry out the following operations: - acceptance of pulses from detection sub-assemblies or other sources; - analogue-to-digital conversion (ADC) of the pulse height information; - sorting of pulse height data according to predetermined characteristics; - storage of digital information (histogram); - processing of stored pulse height histogram and externally supplied information in accordance with predetermined algorithms; - data input and output functions (for example, driving a display, a printer, a floppy disk drive, a plotter, etc.). The above operations may be accomplished separately or combined in an integrated instrument. All the tests described herein are not mandatory, but if the test is carried out, then it shall be done in accordance with the procedures given herein. In many cases in nuclear physics, it is very important to measure the distribution of certain kinds of parameters, such as the energy of particles, their mass, their distribution in time, their scattering on certain angles, etc. In modern measuring practice, this performance is usually accomplished by means of a multichannel pulse height analyzer. This type of a device is built in such a way that a quantity of a certain physical quality is digitized and then stored according to its digitized number. All modern MCAs contain special storing units (memories) for this purpose. After accomplishing the measurement the required information is retrieved from the memory so that it can be used for interpretation of the physical data. Nowadays, multichannel pulse height analyzers are more widely used in different fields of science and industry. Their specific aim in nuclear applications is to transform the pulse height related to a certain nuclear event (usually energy) into a number corresponding to a memory cell, so that during the measurement one can store a histogram that is very similar to the initial pulse height distribution. This distribution reflects the probability density of particle energy (energy spectrum). Using the stored information about the distribution it is easy to determine the information about the initial energy of the particles (alpha and/or beta-particles, gamma and X-quantum, etc.). Further, this information can be used to determine flux densities, dose rates and doses, isotope and element concentrations and contents, etc. Usually, a pulse height analyzer includes an ADC (analogue-to-digital converter), an acquisition unit, a memory, a display and different input/output (I/O) units (display, printer, plotter, etc.). The object of this standard is to present terms and definitions, to list main characteristics of multichannel analyzers, technical requirements and test methods for the following parameters: - minimum and maximum signal pulse heights to be measured; · main error of the minimum and maximum measured signal pulse heights; · instability of the minimum and maximum measured signal pulse heights; · additional errors (or variations) of the minimum and maximum measured signal pulse heights; - channel width; · total error of the channel width; · instability of the channel width; · additional errors of the channel width; - zero point position; · offset; · instability of the zero point; · additional errors of the zero point; - operating range; - integral non-linearity; - differential non-linearity; - dead time; - maximum input pulse rate to be measured; - live time error; - non rectangular factor of channel profile; - system throughput.