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Updated: May 23, 2026
07:31
Characterization of Recombination Effects in a Liquid Ionization Chamber Used for the Dosimetry of a Radiosurgical Accelerator
Published on: May 9, 2014
Application of extrapolation chambers in low-energy X-rays as reference systems
Eric A B da Silva1, Linda V E Caldas
1Instituto de Pesquisas Energéticas e Nucleares, Comissão Nacional de Energia Nuclear, IPEN/CNEN-SP, 05508-000 São Paulo, SP, Brazil.
Summary
Extrapolation chambers, used for measuring radiation doses, effectively measured low-energy X-ray beams in this study. Both commercial and homemade devices demonstrated reliable performance within international standards.
Area of Science:
- Medical Physics
- Radiation Dosimetry
- Instrumentation
Background:
- Extrapolation chambers are specialized instruments primarily designed for measuring low-energy radiation, particularly beta radiation.
- Their application in standard X-ray beams, especially those used in radiotherapy, requires validation of their performance characteristics.
Purpose of the Study:
- To evaluate the performance of both a commercial and a homemade extrapolation chamber when used with standard radiotherapy X-ray beams.
- To assess key dosimetric parameters including stability, linearity, and response characteristics.
Main Methods:
- Measurements were conducted using standard radiotherapy X-ray beams.
- Performance metrics evaluated included saturation curves, polarity effect, short- and medium-term stability, and response linearity.
- Data analysis focused on adherence to International Electrotechnical Commission (IEC) recommendations.
Main Results:
- The obtained saturation curves and polarity effect were within International Electrotechnical Commission (IEC) recommendations.
- Both short- and medium-term stability tests showed results consistent with established standards.
- The response linearity and extrapolation curves demonstrated good performance characteristics.
Conclusions:
- The study confirms the suitability and usefulness of extrapolation chambers for dose measurements in low-energy X-ray beams.
- Both commercial and homemade extrapolation chambers provide reliable data for radiotherapy applications.
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