The Formation, Evolution, and Impact of Wind-Driven Nebulae around Massive Stars

大质量恒星周围风驱动星云的形成、演化和影响

• 批准号: 0319261
• 负责人: Vikram Dwarkadas
• 金额: --
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-10-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0319261&HistoricalAwards=false
• 关键词: Formation; Evolution; Impact; Wind; Driven

AST-0205175PI DwarkadasHot stars, more massive than about eight solar masses, tend to have strong, high-speed outflows of gaseous material, which can result in the formation of wind-blown nebulae around these stars and also can produce effects on the interstellar medium. Recent observations, which have explored the nature of these nebulae with unprecedented resolution, have revealed a variety of aspherical morphologies, with bipolarity being a common theme. Using the theory of radiatively driven winds and numerical simulations, the formation and evolution of these circumstellar nebulae, and the origins of the bipolar structure, will be investigated. These winds are modulated by physical processes such as stellar rotation, gravity darkening, bistability jumps, magnetic channeling of the outflow, and inhomogeneities in the stellar atmospheres. The effect of these processes, both individually and cumulatively, on the latitudinal variation of the winds, and thereby on the morphology of the surrounding nebulae, will be explored. Furthermore, the impact of this circumstellar medium on the subsequent evolution of the massive star as it ends its life in a supernova explosion will be investigated. The results will be compared to recent and archival data in the optical and X-ray regimes. ***

AST-0205175 PI矮星系热恒星的质量超过8个太阳质量，往往有强烈的高速气体流出，这可能导致这些恒星周围形成风吹星云，也可能对星际介质产生影响。最近的观测以前所未有的分辨率探索了这些星云的性质，揭示了各种各样的非球面形态，双极性是一个共同的主题。利用辐射驱动风理论和数值模拟，将研究这些星周星云的形成和演化，以及双极结构的起源。 这些风是调制的物理过程，如恒星旋转，重力暗化，双稳态跳跃，磁沟道流出，和恒星大气的不均匀性。这些过程的影响，无论是单独的和累积的，对纬度变化的风，从而对周围星云的形态，将进行探讨。此外，还将研究这种星周介质对大质量星星在超新星爆炸中结束其生命时随后演变的影响。结果将比较最近和档案数据的光学和X射线制度。***