The fluence rate distributions of neutrons emitted in the reactions of 50 M
eV/u O-18-ion on thick Be, Cu, Au targets were measured with an activation
method of threshold detectors and the neutron dose equivalent rate distribu
tions at Im from the targets in intermediate energy heavy ion target area w
ere obtained using the conversion coefficients for neutron fluence rate to
ambient dose equivalent rate. (C) 2000 Elsevier Science B.V. All rights res
erved.