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Published on: January 28, 2021
Behavior of characteristic X-rays from a partial-transmission-type X-ray target
Hamid Saeed Raza1, Hyun Jin Kim, Jun Mok Ha
1Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), 373-1 Guseong, Yuseong, Daejeon 305-701, Republic of Korea.
Summary
Characteristic X-ray flux from tungsten targets is not isotropic, depending on target thickness and electron beam energy. A new photon generator design uses targets as filters for enhanced X-ray emission.
Area of Science:
- Physics
- Materials Science
Background:
- Characteristic X-rays are crucial in various applications, including medical imaging and materials analysis.
- Understanding their angular distribution is essential for optimizing X-ray source design and performance.
Purpose of the Study:
- To analyze the angular distribution of characteristic X-rays emitted from a partial-transmission tungsten target.
- To investigate the influence of target thickness and incident electron beam energy on X-ray flux.
- To propose a novel multi-energy photon generator design.
Main Methods:
- Utilized Monte Carlo N-Particle (MCNP5) simulations to model X-ray transport.
- Modeled 24 tallies to cover a 360° angular range around the tungsten target.
- Simulated X-ray emission under varying target thicknesses and electron beam energies.
Main Results:
- The characteristic X-ray flux was found to be anisotropic, not uniformly distributed around the target.
- Angular distribution is significantly dependent on tungsten target thickness.
- Incident electron beam energy strongly influences the observed X-ray flux patterns.
Conclusions:
- The study demonstrates that characteristic X-ray emission is direction-dependent.
- Target thickness and electron beam energy are critical parameters for controlling X-ray angular distribution.
- A multi-energy photon generator concept is proposed, utilizing the target as a filter for low-energy X-rays to enhance high-energy emission.
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