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Extending the dynamic range of nuclear pulse spectrometers
A Pullia1, F Zocca, G Pascovici
1Department of Physics, University of Milano, via Celoria 16, I-20133 Milano, Italy.
The Review of Scientific Instruments
|April 2, 2008
Summary
This study introduces novel electronics for high-purity germanium detectors, extending radionuclide spectra analysis beyond analog to digital converter limits. This innovation achieves high spectroscopic resolution across an unprecedented wide energy range for improved nuclear science applications.
Area of Science:
- Nuclear Physics
- Detector Technology
- Spectroscopy
Background:
- Traditional high-purity germanium detectors have limitations in analyzing wide energy ranges due to analog to digital converter (ADC) saturation.
- Extending the measurable energy spectrum is crucial for comprehensive radionuclide analysis.
Purpose of the Study:
- To develop and demonstrate an innovative front-end electronics system for high-purity germanium detectors.
- To extend the measurable radionuclide spectra range beyond the ADC saturation point while maintaining high spectroscopic resolution.
Main Methods:
- Utilized time-varying front-end electronics with a coaxial high-purity germanium detector.
- Implemented automatic signal conditioning for digital-filtering optimization within the ADC range.
- Employed time-over-threshold analysis for signals exceeding the ADC range.
Main Results:
- Achieved a high spectroscopic resolution across both operation ranges (ADC and time-over-threshold).
- Extended the energy range from 5 keV to 150 MeV (90 dB) using a single acquisition chain.
- Demonstrated excellent energy resolution, e.g., 1.3/2.2 keV FWHM for 57Co/60Co gamma lines and <0.4% in the time-over-threshold region.
Conclusions:
- The developed electronics enable unprecedented wide-range energy spectroscopy with high resolution.
- This advancement significantly enhances the capabilities of radionuclide spectrum analysis in nuclear science.
- The single acquisition chain approach simplifies and improves the efficiency of high-energy physics measurements.
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