Abstract
NaI detectors are still used frequently in industrial Prompt Gamma-Ray Neutron Activation Analysis applications such as in bulk material analysis. They have the advantages of being efficient for high-energy gamma rays, being relatively rugged, and being able to be used without cooling. When using NaI detectors, and consequently photomultiplier tubes, the quality of the data can drastically deteriorate through gain and zero shifts that result in spectral smearing due to temperature and/or counting rate changes. A new offline approach is presented to stabilize the NaI spectral drift. The approach is not sensitive to the cause of the drift and takes into account the NaI and ADC non-linearities. Peak resolution is improved substantially when this approach is used in the presence of spectral drift.
| Original language | English |
|---|---|
| Pages (from-to) | 518-521 |
| Number of pages | 4 |
| Journal | Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment |
| Volume | 525 |
| Issue number | 3 |
| DOIs | |
| State | Published - Jun 11 2004 |
| Externally published | Yes |
Funding
The authors are thankful to Jack McKisson of Radiation Technologies, INC. for his constructive suggestions leading to the idea for the approach described herein. The authors also gratefully acknowledge the financial support of: (1) the Associates Program—Nuclear Techniques in Oil Well Logging with present members Baker Atlas, Advantage Engineering, Shell, and ExxonMobil; (2) the US Department of Energy under Grant No. FG07-99ID13775 entitled “Coincidence Prompt Gamma-Ray Neutron Activation Analysis”, and (3) Sabia, Inc. for a Subcontract on the STTR Project with the US Department of Energy entitled “Real-Time Monitoring of Ash, Sulphur, and Elemental Contaminants by Neutron-Gamma Spectroscopy”.
Keywords
- NaI non-linearity
- Spectral drift
- Spectrum stabilization
- Temperature and counting rate drifts