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Published on: May 27, 2018
W values of protons in liquid water
1Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig, Germany. woonyong.baek@ptb.de
Radiation Protection Dosimetry
|May 23, 2007
Summary
The W values for protons in liquid water were calculated using advanced models. Results show W values between 25-26 eV for high-energy protons, differing from water vapor values.
Area of Science:
- Radiation physics
- Chemical physics
Background:
- Accurate W values are crucial for dosimetry and radiation interaction studies.
- Previous calculations may not reflect recent advancements in understanding proton interactions with water.
Purpose of the Study:
- To calculate W values for protons in liquid water across a wide energy range (0.1 keV to 10 MeV).
- To compare results obtained using three recent models for differential ionization cross-sections.
Main Methods:
- Utilized the continuous slowing down approximation (CSDA).
- Employed three distinct, recently published models for calculating differential ionization cross-sections of water for protons.
Main Results:
- Calculated W values for protons in liquid water from 0.1 keV to 10 MeV.
- W values determined by the three models showed marginal differences.
- At proton energies above 5 MeV, W values ranged from 25 to 26 eV.
- This high-energy W value is approximately 3 eV lower than that observed in water vapor.
Conclusions:
- The chosen models provide consistent W value estimations for protons in liquid water.
- The W value in liquid water is notably lower than in water vapor at high proton energies, impacting radiation energy deposition calculations.
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