Building up the Population III initial mass function from cosmological initial conditions
Building up the Population III initial mass function from cosmological initial conditions
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从宇宙学初始条件建立种群 III 初始质量函数
DOI：
10.1093/mnras/stw1728
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发表时间：
2016
影响因子：
4.8
通讯作者：
Aaron T. Lee
中科院分区：
文献类型：
--
作者：
A. Stacy;V. Bromm;Aaron T. Lee
我们从z=100处的宇宙学初始条件出发，模拟了III星族恒星系统的成长。我们跟踪了一个微晕的形成和随后的中心气体坍缩到高密度，解析了小到~ 1 AU的尺度。我们用汇粒子来表示原恒星的生长，模拟了第一个汇周围的光解离和电离区域的生长，并在初始原恒星形成后的约5000年继续模拟。除了第一个形成的汇外，在最大质量恒星周围形成电离锋之前，还会形成几十个次级汇。由此产生的星团在辐射反馈开始前的第一个~ 2000年期间具有高速率的汇形成、恒星盘的抛射和汇合并。到这个时候，一个温暖的~ 5000 K的中性气体阶段已经膨胀到大约2000 AU的圆盘半径，减缓了流入圆盘和下沉的质量。到5000年，最大的恒星的质量增长到20m_sol，而恒星的总质量接近75m_sol。在约40个汇中，大约有30个是低质量的（M_* < 1 M_sol），如果模拟解决了更小的尺度，则可能形成更多的汇。因此，在电离锋出现之前，原恒星的辐射反馈不足以阻止星盘的快速破碎和高成员Pop III星团的形成。在整个模拟过程中，大部分恒星质量都包含在质量最大的恒星中，这进一步表明Pop III的初始质量函数是头重头轻的。
We simulate the growth of a Population III stellar system, starting from cosmological initial conditions at z=100. We follow the formation of a minihalo and the subsequent collapse of its central gas to high densities, resolving scales as small as ~ 1 AU. Using sink particles to represent the growing protostars, we model the growth of the photodissociating and ionizing region around the first sink, continuing the simulation for ~ 5000 yr after initial protostar formation. Along with the first-forming sink, several tens of secondary sinks form before an ionization front develops around the most massive star. The resulting cluster has high rates of sink formation, ejections from the stellar disc, and sink mergers during the first ~ 2000 yr, before the onset of radiative feedback. By this time a warm ~ 5000 K phase of neutral gas has expanded to roughly the disc radius of 2000 AU, slowing mass flow onto the disc and sinks. By 5000 yr the most massive star grows to 20 M_sol, while the total stellar mass approaches 75 M_sol. Out of the ~ 40 sinks, approximately 30 are low-mass (M_* < 1 M_sol), and if the simulation had resolved smaller scales an even greater number of sinks might have formed. Thus, protostellar radiative feedback is insufficient to prevent rapid disc fragmentation and the formation of a high-member Pop III cluster before an ionization front emerges. Throughout the simulation, the majority of stellar mass is contained within the most massive stars, further implying that the Pop III initial mass function is top-heavy.
第一批恒星和星系形成过程中的小规模发电机作用 - I 理想 MHD 极限
影响因子：
6.5
作者：
Schleicher;D. R. G;Banerjee;Arshakian
通讯作者：
Arshakian