The Lead Activation Technique for High Energy Neutron Measurement

The yield of 14-mev pulsed neutron sources may be measured by a detector which counts gamma decay from Pb208(n, 2n) Pb207m and Pb207 (n, n´) Pb2O7m reactions. Threshold for the device is 1.6 mev and the half-life of the Pb207m isomer is 0.8 second; the high sensitivity and the short half-life of a lead counter allow the dectector to be operated in place and at frequent intervals.