AI 中文总结
研究针对高能光子场应用中光核反应建模，用六个单碰撞扫帚柄基准对 OpenMC 光核实现系统验证，与 MCNPX、FLUKA 及解析解比较，量化核数据敏感性，得出不同代码和库在积分中子产额及敏感性上的差异。
AI 中文摘要
光核反应建模在涉及高能光子场的应用中愈发重要，如加速器驱动中子源、辐射屏蔽、医学物理和聚变技术等。蒙特卡罗代码 OpenMC 虽有经充分验证的光原子输运能力，但其光核物理目前仅在非官方开发分支可用，需独立验证。本文基于 2H、9Be 和 238U 靶，用单能 5MeV 和 15MeV 光子以及连续 1 - 20MeV 直线加速器（LINAC）代表性光谱的六个单碰撞扫帚柄基准，对 OpenMC 的光核实现进行系统验证。将 OpenMC 与使用通用 ENDF7u 光核数据的 MCNPX、使用其原生光核模型的 FLUKA 以及积分中子产额的首次碰撞解析解进行比较。还用 IAEA/PD - 2019 库计算以量化核数据敏感性。使用相同 ENDF7u 数据时，OpenMC 和 MCNPX 在所有基准情况下积分中子产额的一致性在 0.7%以内。FLUKA 依赖自身原生光核模型，单能情况与解析解相差约 6 - 9%，连续源情况相差不超过约 4%。将 OpenMC 库改为 IAEA/PD - 2019 时，与基于 ENDF7u 的解析解偏差高达 11.3%，敏感性因核素和源光谱而异。
英文摘要
The modeling of photonuclear reactions is increasingly important for applications involving high-energy photon fields, including accelerator-driven neutron sources, radiation shielding, medical physics, and fusion technologies. Although the Monte Carlo code OpenMC provides well-verified photoatomic transport capabilities, its photonuclear physics is currently available only in an unofficial development branch and requires independent verification before broader scientific use or possible integration into the official code distribution. This work presents a systematic verification of the OpenMC photonuclear implementation using six single-collision broomstick benchmarks based on 2H, 9Be, and 238U targets irradiated by monoenergetic 5 MeV and 15 MeV photons and by a continuous 1--20 MeV linear accelerator (LINAC)-representative spectrum. OpenMC was compared with MCNPX using common ENDF7u photonuclear data, with FLUKA using its native photonuclear models, and with a first-collision analytical solution for the integrated neutron yield. Calculations using the IAEA/PD-2019 library were also performed to quantify nuclear-data sensitivity. OpenMC and MCNPX agreed within 0.7% in integrated neutron yield for all benchmark cases when the same ENDF7u data were used. FLUKA, which relies on its own native photonuclear models rather than ENDF7u, differed from the analytical solution by approximately 6-9% for the monoenergetic cases and by no more than approximately 4% for the continuous-source cases. Changing the OpenMC library to IAEA/PD-2019 produced deviations of up to 11.3% from the ENDF7u-based analytical solution, with the sensitivity varying strongly by nuclide and source spectrum.
