197-Au(n,gamma ) cross section in the unresolved resonance region

Abstract

The cross section of the reaction 197Au(n,γ ) was measured with the time-of-flight technique at the n TOF (neutron time-of-flight) facility in the unresolved resonance region between 5 and 400 keV using a pair of C6D6 (where D denotes 2H) liquid scintillators for the detection of prompt capture γ rays. The results with a total uncertainty of 3.9%–6.7% for a resolution of 20 bins per energy decade show fair agreement with the Evaluated Nuclear Data File Version B-VII.0 (ENDF/B-VII.0), which contains the standard evaluation. The Maxwellianaveraged cross section (MACS) at 30 keV is in excellent agreement with the one according to the ENDF/B-VII.0 evaluation and 4.7% higher than the MACS measured independently by activation technique. Structures in the cross section, which had also been reported earlier, have been interpreted as being due to clusters of resonances.