论文标题

用于核心偏离超新星核合成的示踪剂颗粒:向后移动的优势

Tracer particles for core-collapse supernova nucleosynthesis: The advantages of moving backward

论文作者

Sieverding, Andre, Waldrop, Preston G., Harris, J. Austin, Hix, W. Raphael, Lentz, Eric J., Bruenn, Stephen W., Messer, O. E. Bronson

论文摘要

几十年后,核心偏离超新星爆炸的理论研究正在从参数化的球形对称模型转变为越来越现实的多维模拟。然而,基于这种多维核心折叠超新星(CCSN)模拟,获得核合成的产量并不简单,并且经常采用示踪剂颗粒。示踪剂颗粒可以在模拟期间原位进行原位跟踪,但通常会根据水动力模拟过程中保存的信息在后处理步骤中重建它们。重建可以通过多种方式进行,在这里我们将运动方程方程的向后和正向积分的方法与基于内联粒子轨迹的结果进行比较。我们发现,两种方法都与大量颗粒贡献的同位素的内联结果相当一致。但是,对于仅由少数粒子轨迹产生的稀有同位素,偏差可能很大。对于我们的设置,我们发现向后整合通过更准确地从核统计平衡中冻结后的条件来更好地与内联粒子达成一致性,因为建立核统计平衡可以消除早期详细轨迹的需求。根据我们的结果,如果无法使用直列示踪剂,我们建议向后重建,以至于最后应用了核统计平衡,在最多1 ms的模拟快照之间进行核合成后处理的间隔。

After decades, the theoretical study of core-collapse supernova explosions is moving from parameterized, spherically symmetric models to increasingly realistic multi-dimensional simulations. Obtaining nucleosynthesis yields based on such multi-dimensional core-collapse supernova (CCSN) simulations, however, is not straightforward and frequently tracer particles are employed. Tracer particles may be tracked in situ during the simulation, but often they are reconstructed in a post-processing step based on the information saved during the hydrodynamics simulation. Reconstruction can be done in a number of ways and here we compare the approaches of backward and forward integration of the equations of motion to the results based on inline particle trajectories. We find that both methods agree reasonably well with the inline results for isotopes for which a large number of particles contribute. However, for rarer isotopes that are produced only by a small number of particle trajectories, deviations can be large. For our setup, we find that backward integration leads to a better agreement with the inline particles by more accurately reproducing the conditions following freeze-out from nuclear statistical equilibrium, because the establishment of nuclear statistical equilibrium erases the need for detailed trajectories at earlier times. Based on our results, if inline tracers are unavailable, we recommend backward reconstruction, to the point when nuclear statistical equilibrium last applied, with an interval between simulation snapshots of at most 1 ms for nucleosynthesis post-processing.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源