Effects on Supernovae and their Remnants of Asymmetric Envelopes Caused by Outflow from Binary-star Progenitors

剧烈的星星爆炸，也就是超新星，是宇宙形成的原因。 它们产生并分配了许多重元素，这些重元素构成了恒星、新行星以及人类。超新星释放到星际气体中的能量加热并搅动了星际气体，其中一部分能量被用来加速一些亚原子粒子，使其达到极限能量--充满我们银河系的神秘宇宙射线，并不断落在地球上。 在过去的几千年里，几颗银河系的超新星在地球上可见，并被肉眼观察者仔细记录下来。这些超新星的残余物，膨胀的气体云发射出无线电波，X射线和可见光，现在可以详细研究，沿着数百个来自超新星的更古老的残余物太遥远了，在地球上用肉眼看不到。这个提议将模拟超新星的影响，发生在两颗恒星相互引力束缚的系统中。最近的证据表明，许多超新星起源于双星系统，即成对的恒星相互环绕。 质量越大的恒星随着年龄的增长会脱落物质，特别是在爆炸前的阶段，因此爆炸发生在复杂的气体环境中。 这些研究人员将对超新星爆发前的环境进行最先进的模拟计算，然后对爆炸进行建模，看看爆炸对事件发生时超新星的外观以及事件的残余物有什么影响，这些影响仍然是数千年后的。 研究人员希望能够确定这些超新星和遗迹可能显示的特殊特征，这些特征将成为产生它们的环境的线索。 此外，还将研究一些特殊的天体，如过去几年在地球上看到的超新星的历史遗留物，以试图确定造成爆炸的恒星类型。调查人员将在国家设施中使用高性能计算系统，并将培训学生将最新的计算应用于复杂问题。 提高我们对超新星的理解为我们宇宙的性质和人类在其中的地位的宏大叙事增加了一个重要的部分。

The violent star explosions, known as supernovae, are responsible formany features of our Universe. They produce and distribute many ofthe heavy elements that make up stars, new planets, and also people.The energy supernovae release into the interstellar gas heats and stirs it,and some of that energy goes to accelerating a few subatomic particlesto extreme energies -- the enigmatic cosmic rays that fill our Galaxyand constantly rain down on the Earth. In the last few thousand years,several Galactic supernovae were visible at Earth and carefullyrecorded by naked-eye observers. The remnants of those supernovae,expanding gas clouds emitting radio waves, X-rays, and visible light,can now be studied in detail, along with hundreds of older remnantsfrom supernovae too distant to be seen on Earth with the nakedeye. This proposal will model the effects of supernovae that occur in systems with two stars gravitationally bound to each other. Recent evidence suggests that many supernovae originate in binary systems, pairs of stars orbiting one another. The more massive stars shed material as they age, particularly in the stages just prior to explosion, so the explosions take place in a complicated environment of gas. These investigators will computestate-of-the-art simulations of pre-supernova environments, and then modelthe explosion, to see what effects it has on the appearance of the supernovae at the time of the event, and on the remnants of the events, which are stillthousands of years later. The investigators hope to identify particular features that such supernovaeand remnants might show that would be clues to the environments thatgave rise to them. In addition, a few particular objects, such ashistorical remnants from supernovae seen at Earth in the last fewhundred years, will be studied, to try to identify the types of stars that created the explosions.The investigators will use high-performance computing systems at national facilities, and will train students in the most up-to-date applications of computing to complex problems. Improving our understanding of supernovae adds anessential piece to the grand narrative of the nature of our Universeand the place of humanity in it.