IAEA-TECDOC- 280 DATA ACQUISITION AND ANALYSIS SYSTEMS FOR NUCLEAR RESEARCH AND APPLICATIONS CURRENT STATUS AND TRENDS PROCEEDINGS OF AN ADVISORY GROUP MEETING ORGANIZED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY AND HELD IN VIENNA, AUSTRIA 13-17 SEPTEMBER 1982 | o'0^ AA TECHNICAL DOCUMENT ISSUED BY THE (X) INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1983 Printed by the IAEA in Austria January 1983 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK The IAEA does not maintain stocks of reports in this series However, microfiche copies of these reports can be obtained from INIS Microfiche Clearinghouse International Atomic Energy Agency Wagramerstrasse 5 PO Box 100 A-1400 Vienna, Austria on prepayment of Austrian Schillings 40 00 or against one IAEA microfiche service coupon Foreword For a user of data acquisition and analysis systems for whom such devices are a tool rather than an object of intense and continuing study, it is very difficult to follow the rapid progress of techniques and methods applied in the field. With the fast break-through of micro- processors and computers, the complexity of the instrumentation has reached a level where a scientist must spend much time in mastering the intricacies of his equipment, the programming of his experiments and operating of his computer. In return, he gets better and rapidly evaluated results, more precise control of his experiments and savings in time. For the staff of those laboratories who are at the point of introducing some more advanced, possibly computer-based instrumentation, the problems are more severe. Frequently, such institutions do not have trained staff members who could study the market and select the most suitable equipment. The literature on data acquisition and analysis systems used in nuclear research and technology might be abundant, but is scattered in many different professional journals which are, as a rule, not available in physics, chemistry or biology laboratories in developing countries. The catalogues of commercial manufacturers of nuclear equipment are an excellent source of information; however, they do not present the basis for understanding the present status and trends in the field, and are obviously biased in favour of their own products. The Advisory Group on Data Acquisition Systems in Nuclear Science and Technology was concerned with the objective of reviewing the situation, and assessing possible near-future developments. The papers prepared by the participants, are kept at such a technical level that they can also be studied and appreciated by the reader who is not a specialist in nuclear data handling, and yet provides the necessary inside view of the field. The contributions in the last part of the document are by some commercial manufacturers of nuclear equipment. They are intended as an illustration of the present state-of-the-art. The choice of the represented companies does not reflect any preference on the part of the IAEA in selecting the equipment of a specific manufacturer, and is certainly not intended as an advertisement for their products. It was felt, however, that the document would be more valuable if it would describe some real instruments. With the very fast development of nuclear instrumentation, and particularly the intense application of microprocessors, the commercial products described in this section will soon be replaced by new, more advanced and probably more sophisticated devices. 3 CONTENTS IN TR O D U CTIO N .............................................................................................................................. 7 USERS' EXAMPLES Instrumental aspects of tube-excited energy-dispersive X-ray fluoresence analysis ............................. 13 F. Adams, H. Nullens, P. Van Espen The design of automated nuclear data systems for industnal application ........................................... 45 R.L. Heath BUY OR BUILD Commercially available instrumentation versus custom-made equipment: A Guide........................... 57 D.R. Machen MICROPROCESSOR APPLICATIONS Role of microprocessors in nuclear instrumentation .......................................................................... 63 P. Gallice COMPUTERS Techmques for data acquisition and data analysis ............................................................................. 73 E.C.G. Owen Distributed intelligence versus central laboratory .............................................................................. 93 H. Halling Local area networks for distributed intelligent systems .................................................................... 109 H. Klessmann Interfaces and buses ........................................................................................................................... 133 W. Attwenger Software for nuclear data acquisition systems ................................................................................... 173 P. Christensen MAINTENANCE Preventive maintenance, service and repair of data acquisition and analysis systems .......................... 183 D. V. Camin PRODUCTS Laben's view of the design of data acquisition and processing systems to be used m developing countries ..................................................................................................................... 197 P Casoli, M. Hamel Data acquisition and reduction systems for nuclear data experiments ............................................... 225 KR. Thompson, W. Maier Data acquisition and analysis systems - "Tools of the Trade" ........................................................ 243 KL. Wilson Renner Recent developments in microprocessor-based data systems ............................................................. 69 A.C. Burley The Canberra view of nuclear data acquisition and analysis ............................................................... 285 W. Bernhardt Nuclear instrumentation in a Hungarian research institute for physics ............................................... 301 A. Csdkdny INTRODUCTION The set of papers prepared for the meeting of the Advisory Group, and the discussions can be classified by three categories: (i) Two contributions discuss the application of data acquisition and analysis, as seen by users of such a system in a research and in an industrial development laboratory, respectively. (ii) The present status and envisaged trends of the computer-based or computer-connected systems is reviewed in several papers, from different viewpoints. (iii) The review of some manufacturers are presented in six papers, also giving information on the production lines. A short review is presented below, in the light of the discussions emphasized at the meeting. a. Data acquisition and analysis systems in applied nuclear research The range of equipment used in such experiments is very broad, from the simple counting of radioactive material to activation analysis and Mossbauer spectroscopy. Traditionally, the central unit of equipment is a multichannel analyzer. The recent trend, based on general availability of cheap microcomputers, promotes a more complicated multichannel analyzer, and sophisticated designs which are in fact not necessary for most of the applications. Not all of the advanced features incorporated in such instruments, fulfil the real needs (for example, the video display in colour). In commercial analytical instrumentation, there is a general trend towards the introduction of microprocessors, and provisions for auto- mation, both in control of the instrumentation, and in data reduction. These conveniences involve, however, a risk that the quality of the results, i.e. precision and accuracy pass beyond the control of the experimenter. The experience of well established research laboratories demonstrates that, with time, the commercially available software for data handling is as a rule replaced by home-made programmes which respond better to specific needs. The development of software, obviously, assumes well trained staff. 2. Industrial uses of nuclear data handling systems The instrumentation intended for industrial application must fulfil several conditions: it must permit simplicity and efficiency in hardware and software design, its modules must be expandable, it should possess distributed architecture. 7 Dynamic firmware techniques applied in automated systems for validation of system performance and data presents an important advance to improve reliability and confidence of users of sophisticated equipment. Properly applied in the design of all levels of nuclear data systems, and combined with other hardware diagnostic techniques, this should improve the use of such systems in developing environment. There is much room for improvement in the analog part of electronics: the increase in count rate is an important requirement for many industrial systems, and will be applicable also to data acquisition concepts in different spectroscopy systmes, for example, in chemical analysis. The trend in industrial applictions seems to be the use of commercially available nuclear electronic modules and units; the necessary adaptation to the specific requirements must be made individually for each project, and this part can be very expensive. 3. Commercially available instrumentation versus custom-made equipment The decision on "buy or make" depends on many factors. The definition by three users' groups (see paper of Dr. D.R. Machen) is an effort to classify the requirements in advanced countries, as seen today. The conclusions are valid