Time-resolved neutron radiography using a fast pulse reactor

The feasibility of using a fast pulse reactor as a neutron source in the production of time-resolved neutron radiographs has been demonstrated at the U. S. Army Pulse Radiation Facility. The radiographs were obtained using the transfer radiographic method. Pulses with a full width at half maximum of 50 μsec and 1.2 x 1017 fissions were utilized to obtain time-resolved radiographs of objects moving at speeds up to 76 m/sec. Investigation of double images, observed in radiographs of test objects moving within this speed range, suggests a method of producing ''motion pictures'' of these objects using one reactor pulse and a suitable stack of detection foils. Resolution of objects moving at speeds greater than 76 m/sec can be obtained by reducing source exposure time to a lower limit of 1 μ sec through employment of electronic gating and image intensification techniques. (11 references) (U.S.)