We measured specific activities of the long‐lived cosmogenic radionuclides ⁶⁰Fe in 28 iron meteorites and ⁵³Mn in 41 iron meteorites. Accelerator mass spectrometry was applied at the 14 MV Heavy Ion Accelerator Facility at ANU Canberra for all samples except for two which were measured at the Maier‐Leibnitz Laboratory, Munich. For the large iron meteorite Twannberg (IIG), we measured six samples for ⁵³Mn. This work doubles the number of existing individual ⁶⁰Fe data and quadruples the number of iron meteorites studied for ⁶⁰Fe. We also significantly extended the entire ⁵³Mn database for iron meteorites. The ⁵³Mn data for the iron meteorite Twannberg vary by more than a factor of 30, indicating a significant shielding dependency. In addition, we performed new model calculations for the production of ⁶⁰Fe and ⁵³Mn in iron meteorites. While the new model is based on the same particle spectra as the earlier model, we no longer use experimental cross sections but instead use cross sections that were calculated using the latest version of the nuclear model code INCL. The new model predictions differ substantially from results obtained with the previous model. Predictions for the ⁶⁰Fe activity concentrations are about a factor of 2 higher, for ⁵³Mn, they are ~30% lower, compared to the earlier model, which gives now a better agreement with the experimental data.

中文翻译：

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铁陨石中的 53 Mn 和 60 Fe-新数据、模型计算

我们测量了 28 颗铁陨石中长寿命宇宙放射性核素 ⁶⁰Fe 和 41 颗铁陨石中 ⁵³Mn 的比活度。除了在慕尼黑 Maier-Leibnitz 实验室测量的两个样品外，所有样品都在堪培拉澳大利亚国立大学的 14 MV 重离子加速器设施中应用了加速器质谱法。对于大型铁陨石 Twannberg (IIG)，我们测量了 6 个样品的 ⁵³Mn。这项工作使现有的单个 ⁶⁰Fe 数据的数量增加了一倍，并将为 ⁶⁰Fe 研究的铁陨石数量增加了四倍。我们还显着扩展了整个 ⁵³Mn 铁陨石数据库。铁陨石 Twannberg 的 ⁵³Mn 数据变化超过 30 倍，表明显着的屏蔽依赖性。此外，我们对铁陨石中⁶⁰Fe 和⁵³Mn 的生成进行了新的模型计算。虽然新模型基于与早期模型相同的粒子光谱，但我们不再使用实验横截面，而是使用使用最新版本的核模型代码 INCL 计算的横截面。新模型的预测与先前模型获得的结果有很大不同。⁶⁰Fe 活性浓度的预测值大约高出 2 倍，对于 ⁵³Mn，与早期模型相比，它们的预测值要低约 30%，这使得现在与实验数据更加吻合。