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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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2024 ANS Annual Conference
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Las Vegas, NV|Mandalay Bay Resort and Casino
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The Nuclear Family: Empowering parents and caregivers
The Diversity and Inclusion in ANS Committee is hosting a webinar today to celebrate the contributions of parents in the nuclear industry while fostering diversity and inclusion within the community.
Register now: The webinar, from 1:00-2:00 pm ET, will highlight how the nuclear industry supports caregivers, new parents, and new mothers, and will focus on life transitions and parental responsibilities.
Yonghee Kim, Won Seok Park, Chang Kue Park
Nuclear Science and Engineering | Volume 144 | Number 3 | July 2003 | Pages 227-241
Technical Paper | doi.org/10.13182/NSE03-A2356
Articles are hosted by Taylor and Francis Online.
An importance function of the external spallation neutrons in an accelerator-driven system (ADS) has been introduced and characterized to address the source multiplication in a subcritical blanket. For a model ADS problem with a central external source, the source importance function is evaluated with a neutron transport code system. For a homogeneous core, essential characteristics of the importance are identified from the viewpoint of spatial distributions and energy dependency, etc. The importance function is evaluated for two different beam tube diameters, and its dependency on the buffer thickness is also addressed. In order to assess the impact of the power distribution on the importance function, a heterogeneous core is considered, and its importance function is evaluated. The analyses show that the peak importance occurs in the inner fuel blanket zone, not in the central source region, and the neutron importance in a high-energy regime, above 7 to 20 MeV, is high and increases with the energy. Also, the effects of a neutron absorber on the source importance are studied, and it is found that the source importance could be drastically reduced by surrounding the source with a strong neutron absorber such as B4C. In addition, the source importance function is compared with the conventional -mode adjoint flux, which is used as an importance function of fission neutrons in critical reactors. The comparison reveals that the inhomogeneous source importance function could be quite similar to the homogeneous -mode adjoint flux in both spatial and spectral distributions for a wide range of subcriticality.