Fast procedures for coincidence-summing correction in gamma-ray spectrometry

Simplified and fast procedures for coincidence-summing correction in gamma- ray spectrometry were investigated. These procedures are based on the usual theoretical expressions of the correction factors, but differ in the deter mination of the total efficiency curve based on the following approximation s: (a) replacement. below the knee efficiency value, of the total efficienc y by the full-energy peak efficiency; and (b) use of linear interpolations tin log-log plot) between only two experimental points above the knee effic iency value; or (c) assumption of a peak-to-total efficiency ratio independ ent on the counting geometry; or (d) assumption of a constant relation betw een the peak-to-total efficiency ratios and the photoelectric-to-total cros s section ratios. The above approximations were separately assumed for determination of the c oincidence-summing correction factors for nuclides with complex decay schem e (Ba-133, Cs-134, Eu-152) and for Co-60 and Y-88 measured on a 15% relativ e efficiency p-type coaxial HPGe detector, for three source-detector geomet ries: point source placed on top of and at 10 cm from the detector window, and 1 1 Marinelli beaker filled with aqueous solution, The results were com pared with those based on more accurate experimental determinations of the total efficiency curve from measurements of standard sources of eight diffe rent single-gamma-ray emitters. The usefulness of each simplified procedure is evaluated with respect to its accuracy and to the reduction of the numb er of standard sources and measurement time, (C) 2000 Elsevier Science Ltd. All rights reserved.