Determination of absolute neutron flux by gold activation

With the growing demand for more accurate cross-section determinations precise methods of flux measurement are required. This paper describes a technique for determining the neutron flux in a beam to better than 1 per cent from an absolute measurement of the activity induced in gold foils by neutron capture. The construction of special gridded ionization chambers with 10B layers and their calibration in terms of the gold cross-section to form secondary standards is described.