标题： 早期爆发来自双爆轰型Ia型超新星 显示英文标题

标题： Early Emission from Double Detonation Type Ia Supernovae

摘要： 一种流行的I型超新星（SNe Ia）模型是CO白矮星（WD）的爆轰，这种爆轰是由之前薄层氦的爆轰触发的，被称为双爆轰（DD）。 我们探讨了CO爆轰与He爆轰碰撞所产生的独特早期电磁特征。 这三个特征是（1）一个冲击波爆发闪光，（2）一个平面冲击波爆发冷却阶段，最后是（3）由碰撞释放的热能产生的冲击冷却辐射。 平面阶段的独特之处在于He爆轰层的密度分布不同于通常认为的恒星边缘的陡峭分布。 冲击冷却辐射可能受到复合的影响，我们研究了这些影响。 总的来说，我们预计初始闪光主要由$\sim6\times10^{43}\,{\rm erg\,s^{-1}}$的平面阶段主导，持续时间约为5秒，在软X射线中。 随后是在光学/紫外波段亮度为$3-10\times10^{40}\,{\rm erg\,s^{-1}}$的约12-24小时的冲击冷却阶段。 我们讨论了利用当前和未来的调查项目检测这种早期DD辐射的可能性。 显示英文摘要

摘要： A popular model for Type Ia supernovae (SNe Ia) is the detonation of a CO white dwarf (WD) that is triggered by the prior detonation of a thin surface layer of helium, known as a double detonation (DD). We explore the unique early electromagnetic signatures that are expected from collision of the CO detonation with the He detonation. The three features are (1) a shock breakout flash, (2) a stage of planar shock breakout cooling, and finally (3) shock cooling emission from the thermal energy released by the collision. The planar phase is unique to the unusual density profile of the He-detonated layer in comparison to the steep profile at a stellar edge as is usually considered for shock breakout. The shock cooling emission can be modified by recombination, and we explore these effects. All together, we expect an initial flash dominated by the planar phase of $\sim6\times10^{43}\,{\rm erg\,s^{-1}}$, which lasts ~5 s in the soft X-rays. This is followed by ~12-24 hrs of shock cooling at a luminosity of $3-10\times10^{40}\,{\rm erg\,s^{-1}}$ in the optical/UV. We discuss prospects for detection of this early DD emission with current and upcoming surveys.