H. Yucel et al., USE OF THE 1001 KEV PEAK OF PA-234M DAUGHTER OF U-238 IN MEASUREMENT OF URANIUM CONCENTRATION BY HPGE GAMMA-RAY SPECTROMETRY, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 413(1), 1998, pp. 74-82
For the direct gamma-ray spectrometric measurements of uranium concent
rations in the samples, the use of 1001 keV peak of Pa-234m, second da
ughter of U-238 is emphasized. This ''clean'' peak is well resolved bg
HPGe detectors and gives accurate indication of uranium concentration
in the samples without any self-absorption correction. The 1001 keV p
eak of Pa-234m the U-238 chain is selected because it does not include
any contribution from any other gamma emissions and does not have any
interference with other peaks in the high-energy region even if the s
amples contain high amounts of thorium. The activity of Pa-234m is det
ermined by calibrating a HpGe detector with uranium standards. The mea
surement of 1001 keV gamma-ray emission from Pa-234m by high-resolutio
n gamma-ray spectrometry provides the basis for a reliable determinati
on of U-238 in the samples. The results obtained from the 63.3 keV pea
k of Th-234 and those of the 1001 keV peak from Pa-234m in the U-238 c
hain for the uranium standards are compared with the certified values
of the same samples. The results obtained from the measurements of 100
1 keV peak from Pa-234m agreed to within 2-5% with the certified activ
ity values of U-238 in the samples with uranium content ranging from 0
.014 to 1.02 wt%. The results indicate that the uranium concentrations
in the samples can be determined to within 5% error by about 14 h cou
nting in a HpGe detector system. (C) 1998 Elsevier Science B.V. All ri
ghts reserved.