论文标题
关于核心偏离超新星自洽模型中湍流的特征
On the character of turbulence in self-consistent models of core-collapse supernovae
论文作者
论文摘要
中微子驱动的对流在核心偏离超新星(CCSN)爆炸的发展中起着至关重要的作用。但是,几十年来,触发冲击复兴和随后的爆炸的复杂机制一直无法理解。多维模拟表明,流体不稳定性的生长和湍流对流的发展将决定爆炸的形态。我们已经使用球形极坐标进行了3D模拟,涵盖了降低的角度范围(90度计算结构域),并且具有2度,1度,1/2度和1/4度的角度分辨率,以研究100毫秒的时间尺度上的Core-Collapse超NOVAPLESS爆炸的湍流。我们采用了包括详细的核物理和光谱中微子运输的多物理嵌合体。粗分辨率模型不会发展惯性范围,这大概是由于瓶颈效应,因此可以防止能量降至小尺度,并且倾向于在大尺度上积聚。相反,高分辨率模型开始恢复Kolmogorov理论的k^{ - 5/3}缩放。随机性和很少的模拟样本限制了我们预测爆炸发展的能力。在模拟时间段内,随着角度分辨率的增加,我们的模型在改善(或减少)爆炸条件方面没有明显的趋势。但是,我们发现湍流在冲击背后提供了有效的压力(约为热压的40-50%),这可以有助于减震器的复兴,并有助于爆炸的发展。最后,我们表明,降低角度和全4个PI模型的湍流能量功率谱是一致的,因此表明90度计算域是研究CCSNE中湍流的特征的足够配置。
Neutrino-driven convection plays a crucial role in the development of core-collapse supernova (CCSN) explosions. However, the complex mechanism that triggers the shock revival and the subsequent explosion has remained inscrutable for many decades. Multidimensional simulations suggest that the growth of fluid instabilities and the development of turbulent convection will determine the morphology of the explosion. We have performed 3D simulations using spherical-polar coordinates covering a reduced angular extent (90 degree computational domain), and with angular resolutions of 2 degrees, 1 degree, 1/2 degree, and 1/4 degree, to study the development of turbulence in core-collapse supernova explosions on a time scale of order 100 ms. We have employed the multi-physics Chimera code that includes detailed nuclear physics and spectral neutrino transport. Coarse resolution models do not develop an inertial range, presumably due to the bottleneck effect, such that the energy is prevented from cascading down to small scales and tends to accumulate at large scales. High-resolution models instead, start to recover the k^{-5/3} scaling of Kolmogorov's theory. Stochasticity and few simulation samples limit our ability to predict the development of explosions. Over the simulated time period, our models show no clear trend in improving (or diminishing) conditions for explosion as the angular resolution is increased. However, we find that turbulence provides an effective pressure behind the shock (approx. 40 - 50 % of the thermal pressure), which can contribute to the shock revival and be conducive for the development of the explosion. Finally, we show that the turbulent energy power spectrum of reduced angular extent and full 4 pi models are consistent, thus indicating that a 90 degree computational domain is an adequate configuration to study the character of turbulence in CCSNe.