VULCAN：一个用于系外行星大气的开源、验证过的化学动力学Python代码
VULCAN: an Open-Source, Validated Chemical Kinetics Python Code for Exoplanetary Atmospheres
摘要：
我们提出了一个用于研究热系外行星大气的开源且经过验证的化学动力学代码，我们将其命名为VULCAN。它是为从500到2500 K的气态化学构造的，使用约300个反应的简化C-H-O化学网络。它利用涡流扩散来模拟大气动力学，并排除了光化学。我们提供了一个完整的描述的速率系数和热力学数据。我们通过再现化学平衡并将其输出与Moses等人和Rimmer & Helling的不平衡化学计算进行比较来验证VULCAN。它再现了摩西等人的HD 189733b和HD 209458b模型，它使用了一个有近1600个反应的网络。我们还使用VULCAN来研究温度-压力曲线和碳氧比变化时产生的理论趋势。协助灵敏度测试，旨在确定负责生产一个特定的分子的关键反应，我们重新淬火近似，并发现它是准确的甲烷，但打破了乙炔，因为乙炔的不平衡丰度是不是直接由运输引起的淬火，而是间接控制的不平衡丰度的甲烷。因此，我们建议应谨慎使用猝灭近似，并且必须始终根据化学动力学计算进行检查。使用VULCAN计算的具有100层的一维模型大气通常需要几分钟才能完成。VULCAN是Exoclimes模拟平台（ESP; http：//www.exoclime.net/）的一部分，可在www.example.com上公开获取。
英文摘要：
We present an open-source and validated chemical kinetics code for studying hot exoplanetary atmospheres, which we name VULCAN. It is constructed for gaseous chemistry from 500 to 2500 K using a reduced C-H-O chemical network with about 300 reactions. It uses eddy diffusion to mimic atmospheric dynamics and excludes photochemistry. We have provided a full description of the rate coefficients and thermodynamic data used. We validate VULCAN by reproducing chemical equilibrium and by comparing its output versus the disequilibrium-chemistry calculations of Moses et al. and Rimmer & Helling. It reproduces the models of HD 189733b and HD 209458b by Moses et al., which employ a network with nearly 1600 reactions. We also use VULCAN to examine the theoretical trends produced when the temperature-pressure profile and carbon-to-oxygen ratio are varied. Assisted by a sensitivity test designed to identify the key reactions responsible for producing a specific molecule, we revisit the quenching approximation and find that it is accurate for methane but breaks down for acetylene, because the disequilibrium abundance of acetylene is not directly determined by transport-induced quenching, but is rather indirectly controlled by the disequilibrium abundance of methane. Therefore, we suggest that the quenching approximation should be used with caution and must always be checked against a chemical kinetics calculation. A one-dimensional model atmosphere with 100 layers, computed using VULCAN, typically takes several minutes to complete. VULCAN is part of the Exoclimes Simulation Platform (ESP; http://www.exoclime.net/) and publicly available at http://github.com/exoclime/VULCAN .
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
