论文标题
折叠式积聚磁盘中的核燃烧
Nuclear Burning in Collapsar Accretion Disks
论文作者
论文摘要
巨大的，快速旋转的恒星的核心崩溃被认为是长期伽马射线爆发（GRB）的祖细胞及其相关的超能量超新星（SNE）。在崩溃后的早期，来自恒星恒星包膜的相对较低的角动量材料将循环到位于黑洞地平线外的积聚盘中，从而导致高积聚速率为GRB射流供电所需的高积聚速率。这些小半径处的磁盘中平面中的温度足够高以使核分离，而从磁盘中流出可能是富含中子的，并且可以合成R-Process核。 However, at later times, and for high progenitor angular momentum, the outer layers of the stellar envelope can circularize at larger radii $\gtrsim 10^{7}$ cm, where nuclear reaction can take place in the disk midplane ((e.g.~$^{4}$He + $^{16}$O $\rightarrow$ $^{20}$Ne + $γ$).. Here我们通过流体动力学$α$α$ viscosity torus模拟与19-异位核反应网络相结合的流体动力$α$α$α$α$α$α$α$α$α$α$α$α核反应网络的影响，这些曲线均可模仿折叠时间的倒数时间，这些效果已成为临时的次数，这些效果是临时的几个问题，这些效果是造成的。磁盘流出的积聚与爆炸以及$^{56} $ ni的产生，我们表明，这可能会为GRB超新星提供动力。
The core collapse of massive, rapidly-rotating stars are thought to be the progenitors of long-duration gamma-ray bursts (GRB) and their associated hyper-energetic supernovae (SNe). At early times after the collapse, relatively low angular momentum material from the infalling stellar envelope will circularize into an accretion disk located just outside the black hole horizon, resulting in high accretion rates necessary to power a GRB jet. Temperatures in the disk midplane at these small radii are sufficiently high to dissociate nuclei, while outflows from the disk can be neutron-rich and may synthesize r-process nuclei. However, at later times, and for high progenitor angular momentum, the outer layers of the stellar envelope can circularize at larger radii $\gtrsim 10^{7}$ cm, where nuclear reaction can take place in the disk midplane ((e.g.~$^{4}$He + $^{16}$O $\rightarrow$ $^{20}$Ne + $γ$).. Here we explore the effects of nuclear burning on collapsar accretion disks and their outflows by means of hydrodynamical $α$-viscosity torus simulations coupled to a 19-isotope nuclear reaction network, which are designed to mimic the late infall epochs in collapsar evolution when the viscous time of the torus has become comparable to the envelope fall-back time. Our results address several key questions, such as the conditions for quiescent burning and accretion versus detonation and the generation of $^{56}$Ni in disk outflows, which we show could contribute significantly to powering GRB supernovae. Being located in the slowest, innermost layers of the ejecta, the latter could provide the radioactive heating source necessary to make the spectral signatures of r-process elements visible in late-time GRB-SNe spectra.
