Time-Shared Time-of-Flight Analysis by Computer

Abstract

A time‐shared computer‐centered data collection system has been placed into operation at the Brookhaven Graphite Research Reactor. The system provides simultaneous data collection and sorting for two physically unrelated neutron time‐of‐flight experiments in time‐share with a general computation facility. A general purpose stored‐program digital computer with a 4096 word, 24‐bit memory is the heart of the system. The computer system provides, for the ``fast neutron chopper'' experiment, a 1024‐channel time analyzer for total or partial neutron cross section experiments, three elapsed‐time clocks, three total events scalers, two monitor scalers, and a chopper tachometer. At the same time, for the ``slow neutron chopper'' experiment, the system provides a 256‐channel time analyzer, a clock, a total events scaler, a monitor scaler, and a chopper tachometer. The two experiments are independent of one another and are controlled by the typing of four‐letter mnemonic codes on the system typewriter. A live cathode‐ray tube display of either experiment is present at all times except when the time‐shared computational facility is being used. Connections between the computer and the external analog‐to‐digital converters are made on a patchboard, allowing convenient control of data format. The system has been designed to facilitate expansion to multiparameter data handling.