论文标题
辐射式转移模型，对依克拉尔语中的超新星。在球形对称性中的化学混合的新型处理
Radiative-transfer modeling of supernovae in the nebular-phase. A novel treatment of chemical mixing in spherical symmetry
论文作者
论文摘要
超新星（SN）爆炸通过它们释放的金属，在宇宙的化学演化和生命的起源中起着关键作用。 Nebular相光谱法限制了这种金属产量，例如通过与OI，CAII，FEII或FEIII相关的禁止线发射。爆炸期间的流体不稳定性产生了复杂的3D射流结构，具有相当大的宏观，但没有显微镜的元素混合。该结构为详细的非局部热力学平衡辐射转移模型设定了巨大的挑战，该模型通常仅限于基于网格的代码中的1D。在这里，我们提出了一种新颖而简单的方法，该方法允许宏观混合而无需任何微观混合，从而捕获了SN爆炸中混合的本质。借助这种新技术，宏观混合的喷射是通过在质量空间中改组的，或在速度空间中等效地建造的，这些壳来自未融合的海岸喷射。该方法不需要改变辐射转移，但是需要高空间分辨率来解决组成的快速变化，并以这种洗牌壳结构固有的深度来解决。我们显示了一些15ms祖细胞星的II型SN爆炸的辐射转移模拟的结果。我们的模拟捕获了富含H，He，O或Si的各种壳之间的温度或电离变化。由于非局部能量沉积，伽玛射线渗透到射流的扩展区域，从而使壳体排列的细节不重要。该方法的较高的物理一致性在变形时期提供了光谱特性，这些特性更可靠，尤其是在单个发射线强度方面，这可能有助于限制SN的产量，并且对于核心塌陷SNE，祖细胞质量。该方法适用于所有SN类型。
Supernova (SN) explosions, through the metals they release, play a pivotal role in the chemical evolution of the Universe and the origin of life. Nebular phase spectroscopy constrains such metal yields, for example through forbidden line emission associated with OI, CaII, FeII, or FeIII. Fluid instabilities during the explosion produce a complex 3D ejecta structure, with considerable macroscopic, but no microscopic, mixing of elements. This structure sets a formidable challenge for detailed nonlocal thermodynamic equilibrium radiative transfer modeling, which is generally limited to 1D in grid-based codes. Here, we present a novel and simple method that allows for macroscopic mixing without any microscopic mixing, thereby capturing the essence of mixing in SN explosions. With this new technique, the macroscopically mixed ejecta is built by shuffling in mass space, or equivalently in velocity space, the shells from the unmixed coasting ejecta. The method requires no change to the radiative transfer, but necessitates high spatial resolution to resolve the rapid variation in composition with depth inherent to this shuffled-shell structure. We show results for a few radiative-transfer simulations for a Type II SN explosion from a 15Msun progenitor star. Our simulations capture the strong variations in temperature or ionization between the various shells that are rich in H, He, O, or Si. Because of nonlocal energy deposition, gamma rays permeate through an extended region of the ejecta, making the details of the shell arrangement unimportant. The greater physical consistency of the method delivers spectral properties at nebular times that are more reliable, in particular in terms of individual emission line strengths, which may serve to constrain the SN yields and, for core collapse SNe, the progenitor mass. The method works for all SN types.
