# A Proposal on Evaluation Method of Neutron Absorption Performance to Substitute Conventional Neutron Attenuation Test

• Kim, Jae Hyun (Department of Nuclear Engineering, Hanyang University) ;
• Kim, Song Hyun (Nuclear Fuel Cycle Waste Treatment Research Division, Research Reactor Institute, Kyoto University) ;
• Shin, Chang Ho (Department of Nuclear Engineering, Hanyang University) ;
• Choe, Jung Hun (Ionizing Radiation Center, Nuclear Fuel Cycle Waste Treatment Research Division, Korea Atomic Energy Research Institute) ;
• Cho, In-Hak (Ionizing Radiation Center, Nuclear Fuel Cycle Waste Treatment Research Division, Korea Atomic Energy Research Institute) ;
• Park, Hwan Seo (Ionizing Radiation Center, Nuclear Fuel Cycle Waste Treatment Research Division, Korea Atomic Energy Research Institute) ;
• Park, Hyun Seo (Ionizing Radiation Center, Korea Research Institute of Standards and Science) ;
• Kim, Jung Ho (Ionizing Radiation Center, Korea Research Institute of Standards and Science) ;
• Kim, Yoon Ho (Ionizing Radiation Center, Korea Research Institute of Standards and Science)
• Accepted : 2016.09.12
• Published : 2016.12.31

#### Abstract

Background: For a verification of newly-developed neutron absorbers, one of guidelines on the qualification and acceptance of neutron absorbers is the neutron attenuation test. However, this approach can cause a problem for the qualifications that it cannot distinguish how the neutron attenuates from materials. Materials and Methods: In this study, an estimation method of neutron absorption performances for materials is proposed to detect both direct penetration and back-scattering neutrons. For the verification of the proposed method, MCNP simulations with the experimental system designed in this study were pursued using the polyethylene, iron, normal glass and the vitrified form. Results and Discussion: The results show that it can easily test neutron absorption ability using single absorber model. Also, from simulation results of single absorber and double absorbers model, it is verified that the proposed method can evaluate not only the direct thermal neutrons passing through materials, but also the scattered neutrons reflected to the materials. Therefore, the neutron absorption performances can be accurately estimated using the proposed method comparing with the conventional neutron attenuation test. Conclusion: It is expected that the proposed method can contribute to increase the reliability of the performance of neutron absorbers.

#### Acknowledgement

Supported by : Korea Institute of Energy Technology Evaluation and Planning (KETEP), Innovative Technology Center for Radiation Safety (iTRS)

#### References

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