标题： 镧在55--200 MeV质子诱导反应的测量通过堆叠箔片活化 显示英文标题

标题： Measurement of Proton-Induced Reactions on Lanthanum from 55--200 MeV by Stacked-Foil Activation

摘要： 铈-134是一种同位素，因其作为有前途的治疗放射性核素 $^{225}$Ac 的化学类似物，在生物分布试验中用作短寿命正电子发射同位素 $^{134}$La 的体内发生器，因此被期望用于相关应用。在与通过高能质子轰击镧生产 $^{134}$Ce 相关的50-100 MeV能量范围内，现有的截面数据存在不一致之处，并且在一些重要能量点上存在空白。为解决这些不足，进行了一系列17片 $^{139}$La 薄膜（自然丰度为99.919%）的堆叠靶实验：一个是在LANL的同位素生产设施进行的，入射质子能量为100 MeV；另一个是在BNL的布鲁克海文直线加速器同位素生产商进行的，入射质子能量为200 MeV——这一完整能量范围大约覆盖了55-200 MeV。报告了 $^{139}$La(p,x) 反应的30种产物的截面（代表总非弹性截面的高达55%），此外还包括在用作质子通量监测器的 $^{nat}$Cu 和 $^{nat}$Ti 薄膜中测量的24种残留产物。 测量的$^{139}$La 反应产额与文献数据以及核反应建模代码 TALYS、EMPIRE 和 ALICE 的默认计算结果以及 TENDL-2023 库进行了比较。 默认计算通常表现出较差的预测能力，这是由于该能量范围内的多个相互作用物理模型的复杂性，以及预平衡反应建模的不足。 在之前对这一能量范围内质子诱导反应评估工作的基础上，使用 TALYS-2.0 代码对光学模型和两组分激发子模型进行了参数调整。 这导致了在包括同位素生产在内的应用中，$^{139}$La(p,x) 产额有所改善，优于默认预测结果。 显示英文摘要

摘要： Cerium-134 is an isotope desired for applications as a chemical analogue to the promising therapeutic radionuclide $^{225}$Ac, for use in bio-distribution assays as an in vivo generator of the short-lived positron-emitting isotope $^{134}$La. In the 50-100 MeV energy range relevant to the production of $^{134}$Ce by means of high-energy proton bombardment of lanthanum, existing cross section data are discrepant and have gaps at important energies. To address these deficiencies, a series of 17 $^{139}$La foils (99.919% natural abundance) were irradiated in two stacked-target experiments: one at the LANL's Isotope Production Facility with an incident proton energy of 100 MeV, and a second at BNL's Brookhaven Linac Isotope Producer with an incident proton energy of 200 MeV - a complete energy range spanning approximately 55-200 MeV. Cross sections are reported for 30 products of $^{139}$La(p,x) reactions (representing up to 55% of the total non-elastic cross section), in addition to 24 residual products measured in the $^{nat}$Cu and $^{nat}$Ti foils that were used as proton flux monitors. The measured production cross sections for $^{139}$La reactions were compared to literature data as well as default calculations from the nuclear reaction modeling codes TALYS, EMPIRE and ALICE, as well as the TENDL-2023 library. The default calculations typically exhibited poor predictive capability, due to the complexity of multiple interacting physics models in this energy range, and deficiencies in preequilibrium reaction modeling. Building upon previous efforts to evaluate proton-induced reactions in this energy range, a parameter adjustment procedure was performed upon the optical model and the two-component exciton model using the TALYS-2.0 code. This resulted in an improvement in $^{139}$La(p,x) cross sections for applications including isotope production, over default predictions.