Earticle

초록

영어

Background: X-ray imaging detectors for the nondestructive cargo container inspection using MeV-energy X-rays should accurately portray the internal structure of the irradiated container. Internal and external factors can cause noise, affecting image quality, and scattered radiation is the greatest source of noise. To obtain a high-performance transmission image, the influence of scattered radiation must be minimized, and this can be accomplished through several methods. The scatter rejection method using an anti-scatter grid is the preferred method to reduce the impact of scattered radiation. In this paper, we present an evaluation the characteristics of the signal and noise according to physical and material changes in the anti-scatter grid of the imaging detector used in cargo container scanners. Materials and Methods: We evaluated the characteristics of the signal and noise according to changes in the grid ratio and the material of the anti-scatter grid in an X-ray image detector using MCNP6. The grid was composed of iron, lead, or tungsten, and the grid ratio was set to 2.5, 12.5, 25, or 37.5. X-ray spectrum sources for simulation were generated by 6- and 9-MeV electron impacts on the tungsten target using MCNP6. The object in the simulation was designed using metallic material of various thicknesses inside the steel container. Using the results of the computational simulation, we calculated the change in the scatter-to-primary ratio and the signal-to-noise ratio improvement factor according to the grid ratio and the grid material, respectively. Results and Discussion: Changing the grid ratios of the anti-scatter grid and the grid material decreased the scatter linearly, affecting the signal-to-noise ratio. Conclusion: The grid ratio and material of the anti-scatter grid affected the response characteristics of a container scanner using high-energy X-rays, but to a minimal extent; thus, it may not be practically effective to incorporate anti-scatter grids into container scanners.

목차

ABSTRACT
 Introduction
 Materials and Methods
  1. Anti-scatter grid
  2. Scatter-to-primary ratio (SPR)
  3. Signal-to-noise ratio (SNR) and the SNR improvement factor (KSNR)
  4. Monte Carlo simulation of scattered X-rays
 Results and Discussion
 Conclusion
 Acknowledgements
 References

키워드

저자

• Jeonghee Lee [ Korea Research Institute of Ships & Ocean Engineering, Daejeon, Korea ]
• Chang Hwy Lim [ Korea Research Institute of Ships & Ocean Engineering, Daejeon, Korea ] Corresponding author
• Jong-Won Park [ Korea Research Institute of Ships & Ocean Engineering, Daejeon, Korea ]
• Ik-Hyun Kim [ Korea Research Institute of Ships & Ocean Engineering, Daejeon, Korea ]
• Myung Kook Moon [ Korea Atomic Energy Research Institute, Daejeon, Korea ]
• Yong-Kon Lim [ Korea Research Institute of Ships & Ocean Engineering, Daejeon, Korea ]

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  방사선방어학회지 [Journal of Radiation Protection and Research]

• 간기

  계간

• pISSN

  2508-1888

• 수록기간

  1976~2026

• 등재여부

  KCI 등재,SCOPUS

• 십진분류

  KDC 559 DDC 629