Experience with an On-Line Computing System in Low-Energy Nuclear Physics Experiments
During the past three years, an online computing system has been designed, installed and used extensively in connection with low-energy nuclear physics experiments. The system is used by experimenters and both the 4.5 MeV Van de Graaff and the 12 MeV Tandem accelerators at Argonne National Laboratory. At the heart of the system are two inter-connected small computers (ASI 210 and 2100). These machines have fast operation times and both have 8192 words of core memory. Peripheral devices include punched card and paper tape equipment, typewriters, line-printers, two magnetic tape units, and a display oscilloscope with a "light pen." ASI 210 is interfaced to a 4096-channel pulse-height analyzer and to 4 ADC units in the Tandem experimental area. The ASI 2100 has long-line links to the 4 MeV Van de Graaff and to the laboratory's CDC 3600 central processor. Experiments at both accelerators can interrupt the 3600 and use its high computing power to great advantage. The system is currently being augmented by the addition of the large external core memory (98,304 words) addressable by both small computers. The chief function of this memory is to act as a large two-parameter pulse-height analyzer and as additional storage for program. A special on-line data-handling program has been developed which greatly facilitates the acquisition and manipulation of experimental data. A brief description of the entire system will be given together with a description of the various ways in which it has been used.