论文标题
宇宙射线轨道在天体物理技术中：使用Geant4-DNA蒙特卡洛工具包建模
Cosmic ray tracks in astrophysical ices: Modeling with the Geant4-DNA Monte Carlo Toolkit
论文作者
论文摘要
宇宙射线在星际环境中无处不在，它们轰炸尘土冰盖是形成复杂甚至益生元分子的可能的驱动力。然而，对于这种现象的准确建模至关重要的关键数据，例如无定形固体水（ASW）中宇宙射线轨道的平均半径仍然不受限制。结果表明，ASW中的宇宙射线轨道可以近似为圆柱体积，其平均半径主要与初始粒子能量无关。使用Geant4-DNA Monte Carlo Toolkit模拟了能量离子与低密度无定形（LDA）和高密度无定形（HDA）冰靶之间的相互作用，该冰块允许将二次电子跟踪到材料中的亚克sCitication能量。我们发现LDA和HDA ICES分别为9.9 nm和8.4 nm，发现峰轨道核心半径，$ r_ \ mathrm {cyl} $，略高于天文学模型中通常假设的5 nm的两倍以上。
Cosmic rays are ubiquitous in interstellar environments, and their bombardment of dust-grain ice mantles is a possible driver for the formation of complex, even prebiotic molecules. Yet, critical data that are essential for accurate modeling of this phenomenon, such as the average radii of cosmic-ray tracks in amorphous solid water (ASW) remain unconstrained. It is shown that cosmic ray tracks in ASW can be approximated as a cylindrical volume with an average radius that is mostly independent of the initial particle energy. Interactions between energetic ions and both a low-density amorphous (LDA) and high-density amorphous (HDA) ice target are simulated using the Geant4-DNA Monte Carlo toolkit, which allows for tracking secondary electrons down to subexcitation energies in the material. We find the peak track core radii, $r_\mathrm{cyl}$, for LDA and HDA ices to be 9.9 nm and 8.4 nm, respectively - somewhat less than double the value of 5 nm often assumed in astrochemical models.
