The Development of Explosions in Axisymmetric Ab Initio Core-Collapse Supernova Simulations of 12-25 $M_\odot$ Stars
Stephen W. Bruenn, Eric J. Lentz, W. Raphael Hix, Anthony Mezzacappa, James Austin Harris, O. E. Bronson Messer, Eirik Endeve, John M. Blondin, Merek Austin Che… 展开作者
Stephen W. Bruenn, Eric J. Lentz, W. Raphael Hix, Anthony Mezzacappa, James Austin Harris, O. E. Bronson Messer, Eirik Endeve, John M. Blondin, Merek Austin Chertkow, Eric J. Lingerfelt, Pedro Marronetti, Konstantin N. Yakunin
备注：
39 pages, 29 figures, accepted for publicatoin in The Astrophysical Journal, additional animations available at ChimeraSN.org
We present four ab initio axisymmetric core-collapse supernova simulations for 12, 15, 20, and 25 $M_\odot$ progenitors. All of the simulations yield explosions and have been evolved for at least 1.2 seconds after core bounce and 1 second after material first becomes unbound. Simulations were computed with our Chimera code employing spectral neutrino transport, special and general relativistic transport effects, and state-of-the-art neutrino interactions. Continuing the evolution beyond 1 second allows explosions to develop more fully and the processes powering the explosions to become more clearly evident. We compute explosion energy estimates, including the binding energy of the stellar envelope outside the shock, of 0.34, 0.88, 0.38, and 0.70 B ($10^{51}$ ergs) and increasing at 0.03, 0.15, 0.19, and 0.52 B s$^{-1}$, respectively, for the 12, 15, 20, and 25 $M_\odot$ models. Three models developed pronounced prolate shock morphologies, while the 20 $M_\odot$ model, though exhibiting lobes and accretion streams like the other models, develops an approximately spherical, off-center shock as the explosion begins and then becomes moderately prolate $\sim$600 ms after bounce. This reduces the explosion energy relative to the other models by reducing mass accretion during the critical explosion power-up phase. We examine the growth of the explosion energy in our models through detailed analyses of the energy sources and flows. We find that the 12 and 20 $M_\odot$ models have explosion energies comparable to that of the lower range of observed explosion energies while the 15 and 25 $M_\odot$ models are within the range of observed explosion energies, particularly considering the rate at which their explosion energies are increasing. The ejected $^{56}$Ni masses given by our models are all within observational limits as are the proto-neutron star masses and kick velocities. (Truncated)
An axisymmetric shock breakout indicated by prompt polarized emission from the type II supernova 2024ggi
Tsinghua University（清华大学）；Beijing Normal University（北京师范大学）；Texas A&M University（德克萨斯农工大学）；European Organisation for Astronomical Research in the Southern Hemisphere (ESO)（欧洲南方天文台）；University of Texas at Austin（德克萨斯大学奥斯汀分校）；University of California, Berkeley（加州大学伯克利分校）；Weizmann Institute of Science（魏茨曼科学研究所）；Royal Holloway, University of London（伦敦大学皇家霍洛威学院）
The impact of nuclear equations of state on the dynamics and multi-messenger emission of magnetorotational stellar explosions
Università di Firenze（佛罗伦萨大学）；INAF, Osservatorio Astrofisico di Arcetri（意大利国家天体物理研究所阿切特里天文台）；INFN, Sezione di Firenze（意大利国家核物理研究所佛罗伦萨分部）；Université Paris-Saclay（巴黎萨克雷大学）；Université Paris Cité（巴黎西岱大学）；CEA（法国原子能和替代能源委员会）；CNRS（法国国家科学研究中心）；Institut d’Astrophysique de Paris（巴黎天体物理研究所）；Sorbonne Université（索邦大学）；Universitat de València（瓦伦西亚大学）；Observatori Astronòmic, Universitat de València（瓦伦西亚大学天文观测站）
Matter mixing in aspherical core-collapse supernovae: a search for possible conditions for conveying $^{56}$Ni into high velocity regions
我们进行了二维轴对称流体动力学模拟的物质混合在非球面核心坍缩超新星爆炸的16.3 $M_{\odot}$星与紧凑的氢信封。SN 1987 A的观测提供了证据，证明由爆炸核合成合成的$^{56}$ Ni混合到爆炸恒星中快速移动的物质（$\gtrsim$ 3，500 km s $^{-1}$）中。为了阐明再现这种高速度的$^{56}$ Ni的关键条件，我们重新审视了非球面核塌缩超新星爆炸中的物质混合。通过在铁芯和富硅层之间的界面周围注入热能和动能，人为地引发爆炸。径向速度中5%或30%幅度的扰动在几个时间点引入。我们发现，没有高速$^{56}$镍可以得到，如果我们考虑双极爆炸与扰动（5%振幅）的前超新星起源。如果在冲击波到达氢包层之前的后期阶段，由于某种未知机制而引入或存在大的扰动（30%振幅），则可以获得速度为3，000 km s的$^{-1}$的$^{56}$ Ni。本文研究了初始激波中具有团簇结构的沿赤道面不对称的非球形爆炸。我们发现，团块大小影响$^{56}$ Ni的渗透。最后，我们报告说，一个非球面爆炸模型，是不对称的赤道平面与多个扰动的前超新星起源可能会导致穿透的$^{56}$镍块到3,000公里的快速移动的物质$^{-1}$。我们表明，这两个非球面爆炸与cluerous结构和扰动的前超新星起源可能是必要的复制所观察到的高速度的$^{56}$镍。为了证实这一点，需要更强大的…
A three-dimensional hydrodynamics simulation of oxygen-shell burning in the final evolution of a fast-rotating massive star
我们第一次进行了一个3D流体动力学模拟的最后几分钟前崩溃的快速旋转的大质量恒星的氧壳的演变。这颗恒星的初始质量为38 M $_\odot$，金属丰度为$\sim$ 1/50 Z $_\odot$，初始自转速度为600 km s $^{-1}$，并且经历化学均匀演化。它在（4.7-17）$\times 10^{8}$ cm处有一个富硅富氧（Si/O）对流层，在那里发生氧壳燃烧。湍流速度的功率谱分析表明，占主导地位的大尺度模式（$\ell \sim 3$），这也被认为是在非旋转的恒星，有一个广泛的Si/O层。在Si/O壳层的赤道面出现了致密的螺旋臂结构和氧壳层燃烧产生的富硅物质。非轴对称大尺度（$m \le 3$）模式在这些结构中占主导地位。螺旋臂结构在以前的非旋转3D前超新星模型中还没有被发现。在这种对流模式的支配下，角平均比角动量在Si/O对流层中变为常数，这在球对称恒星演化模型中是没有考虑的。这样的旋臂和恒定的特定角动量可能会影响恒星随后的爆炸或坍缩。
