Continuous versus pulse neutron induced gamma spectroscopy for soil carbon analysis

• Published in: Applied radiation and isotopes 2015-02, Vol.96, p.139-147
• Main Authors: Kavetskiy, A., Yakubova, G., Torbert, H.A., Prior, S.A.
• Format: Article
• Language: English
• Subjects: Inelastic neutron scattering; Neutron generator; Soil analysis; Soil carbon; Thermo neutron capture
• ISSN: 0969-8043; 1872-9800
• DOI: 10.1016/j.apradiso.2014.10.024

Neutron induced gamma spectra analysis (NGA) provides a means of measuring carbon in large soil volumes without destructive sampling. Calibration of the NGA system must account for system background and the interference of other nuclei on the carbon peak at 4.43MeV. Accounting for these factors produced measurements in agreement with theoretical considerations. The continuous NGA mode was twice as fast and just as accurate as the pulse mode, thus this mode was preferable for routine soil carbon analysis. •Calibration of the neutron induced gamma analysis system must account for system background and the interference of other nuclei (mainly silicon-28) on the carbon peak at 4.43MeV.•Spectra measured at a height of 250cm above the ground could be considered the NGA system background spectrum.•The experimental cascade transition coefficient for silicon-28 (i.e. ratio of 4.50–1.78MeVgamma ray intensities) agrees well with theoretical calculations.•The NGA continuous working mode halved the measurement time compared to the pulse working mode while retaining the same degree of accuracy.