The Use of a Digital Computer in Time-of-Flight Experiments

A general-purpose digital computer has been incorporated as an integral part of a data acquisition and processing system for use in neutron time-of-flight experiments. The system has been used successfully in experiments designed to measure the neutron capture and fission cross sections of U235, U233, and Pu239 as a function of neutron energy. A digital computer was chosen for these experiments because of the increased data handling capacity that could be attained as compared to that attained with a conventional analyzer. In the application of the latter to time-of-flight spectroscopy, the channel width Δt is chosen to meet the energy resolution required by the experiment. The computer was programmed to simulate a series of analyzers, each having a channel width appropriate for the energy region covered. Eight regions were used with the channel width changing by a factor of 2 in successive regions. The recording of data in this manner greatly increases the time range which can be covered without sacrificing energy resolution. With the computer the increased flexibility in the control of the experiments can also be obtained. Another feature which has proved very useful is the scope display which permits a detailed visual inspection of the data during the experiment.