AI 中文总结
本研究借助 TITAN 装置首次测量五种丰中子 Cs、Ba 同位素质量，将其应用于 r-过程核合成模拟，发现新质量数据可消除 $A\sim150$ 附近丰度预测的奇偶效应，调整裂变碎片分布并影响恒星丰度比对比。
AI 中文摘要
我们利用 TRIUMF 的 TITAN 装置，通过飞行时间测量技术首次测量了五种丰中子同位素的质量，分别为 $^{149-151}$Cs 和 $^{151, 152}$Ba。我们将这些质量数据应用于模拟中子星并合中快中子俘获过程（r-过程）核合成所需的核反应与衰变数据。研究表明，这些丰中子质量会影响质量数 $A\sim148-152$ 附近的丰度预测，对应原子序数 $Z=60、62$ 和 63 的镧系元素丰度。我们进一步证实，这些新的 TITAN 质量数据会消除 $A\sim150$ 附近同位素丰度预测中的奇偶效应，该效应在裂变循环天体物理条件及未达到锕系元素的条件下均存在。此外，这些新质量数据会调整裂变碎片在形成最终丰度时的分布，并会影响与恒星丰度比（如 [Ag/Eu]、[Sm/Eu] 和 [Nd/Eu]）对比的结果。
英文摘要
We present measurements for the masses of five neutron-rich isotopes, $^{149-151}$Cs and $^{151, 152}$Ba, probed for the first time by TITAN at TRIUMF with time-of-flight measurement techniques. We propagate these masses to the nuclear reaction and decay data required for the simulation of the rapid neutron capture process (r-process) nucleosynthesis in neutron star mergers. We show that these neutron-rich masses affect the abundance predictions near mass number $A\sim148-152$ corresponding to lanthanide element abundances at $Z=60,\,62$ and $63$. We demonstrate that these new TITAN masses smooth out the odd-even effect in isotopic abundance predictions near $A\sim150$ in both fission cycling astrophysical conditions and conditions that do not reach actinides. We further show that these new masses adjust how fission fragments settle into place when forming the final abundances, and consider the effect on comparisons with stellar abundance ratios such as [Ag/Eu], [Sm/Eu], and [Nd/Eu].
Commentssubmitted
