Prompt \(\gamma \)-ray spectra emitted in fast-neutron induced fission of \(^{239}\)Pu have been recently measured by using the LICORNE directional neutron source at E\(_n\) = 1.8 MeV. The results are used in parallel with the measurements of fast-neutron induced fission of \(^{238}\)U and spontaneous fission of \(^{252}\)Cf to assess the potential of such reactions and observables, in contributing to the understanding of fission. The \(\gamma \)-ray spectra were measured and analyzed under similar conditions, allowing a consistent and robust comparison between the three systems. They are further compared to Monte–Carlo simulations based on two widely-used semi-empirical codes, FREYA and GEF. Differences in the low and high energy portions of the spectrum are interpreted based on simple arguments involving nuclear structure and evaporation effects. The significance and potential of experimental campaigns of this kind, as well as current limitations, are highlighted, together with straightforward but mandatory extensions.

中文翻译：

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快速中子诱发裂变的快速$$ \γ$$γ射线发射研究的潜力：第一步

提示\（\伽马\）射线谱中的快中子诱发裂变发射\（^ {239} \）莆已使用独角兽定向中子源E处被最近测量\（_Ñ\） = 1.8兆电子伏。将结果与快中子诱发的\（^ {238} \） U裂变和\（^ {252} \） Cf的自发裂变的测量结果并行使用，以评估此类反应和可观测物的潜力了解裂变。的\（\伽马\）在相似的条件下测量和分析X射线光谱，从而可以在三个系统之间进行一致且可靠的比较。将它们与基于两种广泛使用的半经验代码FREYA和GEF的蒙特卡洛模拟进行了比较。基于涉及核结构和蒸发效应的简单论点来解释光谱的低能和高能部分的差异。强调了这种实验性运动的重要性和潜力以及当前的局限性，以及直接但强制性的扩展。