论文标题
AGN磁盘的恒星进化
Stellar Evolution in AGN Disks
论文作者
论文摘要
主动银河核由中央超级黑洞周围的几何含量积聚磁盘提供动力。在这里，我们探讨了嵌入在这些极端天体物理环境中（AGN恒星）中的恒星的演变。由于AGN磁盘比星际介质要热得多，因此AGN恒星的边界条件与正常恒星非常不同。它们也受到质量积聚的强烈影响，鉴于大量磁盘和超级 - 埃德丁顿风造成的质量损失可能会失控。此外，化学混合在这些恒星的演变中起着至关重要的作用，这使得从磁盘中积聚的新氢将其混合到核心中。我们发现，根据局部AGN密度和声速以及AGN相的持续时间，AGN星可以迅速变得非常大（m> 100 m $ $ _ \ odot $）。这些恒星发生核心爆发，留下紧凑的残留物，并用重元素污染磁盘。我们表明，AGN恒星的演变可以对AGN金属性的演变以及Ligo-Virgo观察到的引力波的产生产生深远的影响。我们将银河中心指向一个非常适合测试我们对这种异国情调恒星进化通道的预测的区域。
Active Galactic Nuclei are powered by geometrically-thin accretion disks surrounding a central supermassive black hole. Here we explore the evolution of stars embedded in these extreme astrophysical environments (AGN stars). Because AGN disks are much hotter and denser than the interstellar medium, AGN stars are subject to very different boundary conditions than normal stars. They are also strongly affected by both mass accretion, which can runaway given the vast mass of the disk, and mass loss due to super-Eddington winds. Moreover, chemical mixing plays a critical role in the evolution of these stars by allowing fresh hydrogen accreted from the disk to mix into their cores. We find that, depending on the local AGN density and sound speed and the duration of the AGN phase, AGN stars can rapidly become very massive (M > 100 M$_\odot$). These stars undergo core-collapse, leave behind compact remnants and contribute to polluting the disk with heavy elements. We show that the evolution of AGN stars can have a profound impact on the evolution of AGN metallicities, as well as the production of gravitational waves sources observed by LIGO-Virgo. We point to our galactic center as a region well-suited to test some of our predictions of this exotic stellar evolutionary channel.
