Absolute Calibration of a Prompt Gamma-Ray Detector for Intense Bursts of Protons

A detector for determining the intensity and duration of kiloampere pulsed proton beams is described. Proton intensities are inferred from measurements of prompt gamma rays of 6 to 7 MeV from the 19F(p, αγ)16O reaction. The thick-target yield for this reaction on a Teflon target was measured for 0.5-to 2.8-MeV protons. Two different size detectors were calibrated absolutely using the continuous proton beam from a Van de Graaff accelerator. An absolute measurement of a kiloampere pulsed proton beam is described, and the measured current is in agreement with an independent determination of the total proton intensity by nuclear activation.