s __ __ ~ NOM zyxwvutsrqp B Beem Interactions with Materiels 8 Atoms Nuclear instruments and Methods in Physics Research B 130 (1997) 123- 126 ELSEXIER New CAMAC based data acquisition and beam control system for Lund nuclear microprobe Mikael Elfman *, Per Kristiansson, Klas Malmqvist, Jan Pallon, Anders Sjijland, Rogerio Utui, Changyi Yang zyxwvutsrqponmlkjihgfedcbaZYXWVU Department zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA of Nuclear Physics, Lund Institure zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCB of Technology, Unicersity of Lund. P.O. 30.x 118. S-221 00 Lund. Sweden zyxwvutsrqponm Abstract A new CAMAC based data acquisition system has been installed at the Lund Nuclear Microprobe facility. This paper reports on the development and present status of the data acquisition system. The system is a true multiparameter CAMAC based system with fast Fera bus readout and in crate memory buffer. The user interface is based on Sparrow Kmax software for a Power Macintosh platform. The system read out and tag the event data with position on-line, which make fast on-line monitoring of spectra or element maps possible. Simultaneously, all data can be saved event by event for off-line analysis. The beam scanning part is software controlled through a timed D/A converter, this allows fast scanning of the beam, With a CCD-camera and video card the area to be analysed could be defined directly from the image, and the sample position can be moved. Any kind of irregular scan patterns could be defined. 1. Introduction One of the most important parts of a scanning nuclear microprobe is the data acquisition and han- dling system. Since a great variety of analytical methods can be used separately or simultaneously for analysis (PIXE, Rutherford backscattering (RBS), STIM, Nuclear Reaction Analysis (NRA) 111, the requirements on the system are fairly complex and a lot of different demands must be satisfied. A com- plete integrated system should in a user friendly way be able to acquire data, sort and present it in on-line mode as well as in a event by event storage list mode for off-line processing. Other demands for the sys- tem is true coincidence multiparameter data acquisi- * Corresponding author. Fax: + 46-46-2224709; email: mikael.elfman@nuclear.lu.se tion for many parameters, and easy beam and sample movement control. The possibility to choose any beam scanning pattern, scanned at a broad range of frequencies and triggered with any signal (charge, X-ray counts) is required. Some of the methods need very high count-rates @TIM, RBS, Secondary Elec- tron Images), therefore a high maximum data throughput is needed. In this paper we give a short description of the facilities of the new data acquisi- tion system that has been introduced at the Lund Nuclear Microprobe (LNMP) [2]. This new data acquisition system will replace our old system de- scribed in Refs. 134. 2. The hardware The system is based on the well defined CAMAC standard. The hardware consists of a CAMAC crate 0168-583X/97/$17.00 0 1997 Published by Elsevier Science B.V. All rights reserved. P11SO168-583X(97)00271-1 III. DATA ACQUISITION AND ANALYSIS