标题： Ia型超新星爆炸在双简并合并三维流体动力学模拟中的证据 显示英文标题

标题： Evidence of .Ia Supernova Detonations in 3D Hydrodynamical Simulations of Double Degenerate Mergers

摘要： 我们报告了1.1$\mathrm{M_{\odot}}$氧-氖（ONe）白矮星（WD）与0.35$\mathrm{M_{\odot}}$氦WD合并的详细三维模拟，这些模拟使用了移动网格流体动力学代码AREPO。 模拟中使用了由包含半简并碳燃烧效应的恒星演化代码生成的一级WD自洽化学分布。 我们发现，在氦层底部点燃了氦爆炸，引发热核失控，围绕WD并以次光度超新星的形式喷射物质。 我们的典型模拟（C-120）在喷射出主要为$\mathrm{M_{\odot}}$的$^{4}\mathrm{He}$、$^{28}\mathrm{Si}$和$^{32}\mathrm{S}$后，一级开始再次从幸存的二级吸积。 我们的结果定性上依赖于“螺旋时间”模拟参数，该参数描述了角动量加速损失的时期长度。 例如，当螺旋时间过长时，双星系统无法存活。 我们比较了使用自洽化学分布的结果与恒定组成WD结构的结果，发现当螺旋时间较短时，爆炸模式相同。 然而，通过使用恒定组成结构和长螺旋时间，我们能够获得典型的Ia型超新星（SN Ia），该超新星摧毁了一级。 此模拟中的冲击波汇聚遵循Gronow等人在2020年描述的“x剪刀机制”，由于汇聚点处更高的温度和更高的$^{12}\mathrm{C}$数密度，导致二次爆炸。 这些结果突显了在模拟中引入不现实的大角动量损失增强和（或）不现实的一级WD化学结构时可能导致不现实结果的潜力。 显示英文摘要

摘要： We report detailed 3D simulations of 1.1 $\mathrm{M_{\odot}}$ Oxygen-Neon (ONe) white dwarfs (WDs) merging with a 0.35 $\mathrm{M_{\odot}}$ helium WD, conducted with the moving-mesh hydrodynamic code AREPO. The simulations utilise self-consistent chemical profiles for the primary WD which were generated by a stellar evolution code incorporating the effects of semi-degenerate carbon burning. We find that a helium detonation is ignited at the base of the helium layer, starting a thermonuclear runaway which encircles the WD and ejects material as a sub-luminous supernovae. Our canonical simulation, (C-120), ejects 0.103 $\mathrm{M_{\odot}}$ of primarily $^{4}\mathrm{He}$, $^{28}\mathrm{Si}$, and $^{32}\mathrm{S}$, after which the primary begins accreting again from the surviving secondary. Our results depend qualitatively on the "inspiral time" simulation parameter, which describes the length of a period of accelerated angular momentum loss. For example, the binary does not survive when inspiral time is too long. We compare the results using our self-consistent chemical profiles to a constant-composition WD structure and find the same explosion pattern when the inspiral time is short. However, we are able to obtain a typical Type Ia supernova (SN Ia) which destroys the primary by using the constant-composition structure and long inspiral. The shock-convergence in this simulation follows the "x-scissor mechanism" described by Gronow et al. in 2020, and causes a secondary detonation due to higher temperatures and higher number density of $^{12}\mathrm{C}$ at the convergence site. These results highlight the potential for unrealistic outcomes when conducting simulations that incorporate unrealistically large enhancements in angular momentum losses and (or) non-realistic chemical structures for the primary WD.