Электронный каталог

Статья

Le, V.-H.
Application of a "Source-Replay"-Based Monte Carlo Simulation for Evaluating Thermal and Epithermal Neutron Self-Shielding Factors at IREN / V.-H.Le, T.-T.Pham, H.-K.Le, Duc Cong Vu, X.-T.Nguyen, V.N.Shvetsov, A.Yu.Dmitriev, [a.o.]. – Text : electronic // Nuclear Instruments & Methods in Physics Research A. – 2026. – Vol. 1089. – P. 171610. – URL: https://doi.org/10.1016/j.nima.2026.171610. – Bibliogr.: 33.

This study employs an efficient source-replay Monte Carlo strategy using the Particle and Heavy Ion Transport Code System (PHITS) to calculate neutron self-shielding factors (g-factors) at the Intense Resonance Neutron Source (IREN) facility, Joint Institute of Nuclear Research (JINR), Russia. By decoupling source characterization from specimen transport, the method reduces total computational time from several months to a one-month initialization followed by only minutes per specimen. Four specimens (Au, Cu, W, and Zr) were considered. Validation was performed via a multi-tiered process, including cross-code and published benchmark comparisons, together with experimental measurements involving Au and W monitors at main irradiation position at the IREN facility. Thermal and epithermal g-factors obtained using the PHITS code differ from those obtained using the Monte Carlo N-Particle Transport Code version 6 (MCNP6) within 6%. The relative differences between simulated ones for Au and W and those experimentally determined are also less than 6%. Compared with published benchmarks, IREN-derived factors align with datasets representing similar directional neutron field characteristics, while diverging from those based on idealized isotropic distributions. Thanks to the computational efficiency of the source-replay strategy, a detailed parametric survey has been carried out, revealing the sensitivity of g-factors to beam divergence. For example, shifting the irradiation position from 50 mm to 170 mm from the converter's front face caused a measurable augmentation in self-shielding. This work establishes a specialized implementation and rigorous validation of the source-replay strategy coupled with the PHITS code. By addressing the computational bottlenecks associated with complex, indirect neutron generation, it provides a reproducible and scalable framework for high-precision Neutron Activation Analysis (NAA) in non-uniform neutron fields.



Спец.(статьи,препринты) = С 413 д - Активационный анализ
Спец.(статьи,препринты) = С 17 б - Численное интегрирование. Методы Монте-Карло
ОИЯИ = ОИЯИ (JINR)2026