We performed polarized neutron reflectometry measurements on a 78 nm-thick Au97Fe3 film prepared on a thermally oxidized Si wafer. The measurements were done on the C5 spectrometer at Chalk River in reflectometry mode. We determined the magnetization of the specimen in a vertical magnetic field of 6 T in a temperature range from 300 to 1.5 K. We observed a cusp in the magnetization at about 10 K, close to the spin-glass freezing temperature of 16 K of a bulk Au97Fe3 alloy. From the fit to the reflectivity data we can infer a magnetic moment of 0.63 mu(B) per Fe atom at the cusp position which is a large reduction compared to the bulk value of 1.2 mu(B) per Fe atom. Crown Copyright (c) 2006 Published by Elsevier B.V. All rights reserved.