The impact of r -process heating on the dynamics of neutron star merger accretion disc winds and their electromagnetic radiation
The impact of r -process heating on the dynamics of neutron star merger accretion disc winds and their electromagnetic radiation
复制标题
r过程加热对中子星并合吸积盘风动力学及其电磁辐射的影响
DOI：
10.1093/mnras/stab3583
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发表时间：
2021
影响因子：
4.8
通讯作者：
Fernández, Rodrigo
中科院分区：
文献类型：
--
作者：
Klion, Hannah;Tchekhovskoy, Alexander;Kasen, Daniel;Kathirgamaraju, Adithan;Quataert, Eliot;Fernández, Rodrigo
中子星星的合并吸积盘可以发射大于10− 2 M的富中子风。这些喷出物是r过程核合成的主要场所，它将产生一系列放射性重核。这些原子核的衰变释放出足够的能量，使部分风加速0.1c。在这里，我们调查的影响r-过程加热盘风的动力学演化。我们提取风从一个3D的广义相对论磁流体动力学模拟的磁盘合并后的系统。这用于为2D流体动力学模拟创建内部边界条件，以继续原始3D模拟。我们进行两个这样的模拟：一个包括热过程加热，另一个不包括。我们遵循流体动力学模拟，直到风达到同源（60 s）。使用随时间变化的多频多维Monte Carlo辐射输运模拟，然后我们计算的kilonova光变曲线从风与无dynamicalr过程加热。我们发现，热过程加热可以大大改变风的速度分布，移动的质量加权中值速度从0.06c到0.12c。动力学过程加热的加入使光变曲线在合并后更亮更蓝。然而，喷出物分布的高速尾部和早期（）光变曲线基本上不受影响。
Neutron star merger accretion discs can launch neutron-rich winds of >10−2M⊙. This ejecta is a prime site forr-process nucleosynthesis, which will produce a range of radioactive heavy nuclei. The decay of these nuclei releases enough energy to accelerate portions of the wind by ∼0.1c. Here, we investigate the effect ofr-process heating on the dynamical evolution of disc winds. We extract the wind from a 3D general relativistic magnetohydrodynamic simulation of a disc from a post-merger system. This is used to create inner boundary conditions for 2D hydrodynamic simulations that continue the original 3D simulation. We perform two such simulations: one that includes ther-process heating, and another one that does not. We follow the hydrodynamic simulations until the winds reach homology (60 s). Using time-dependent multifrequency multidimensional Monte Carlo radiation transport simulations, we then calculate the kilonova light curves from the winds with and without dynamicalr-process heating. We find that ther-process heating can substantially alter the velocity distribution of the wind, shifting the mass-weighted median velocity from 0.06cto 0.12c. The inclusion of the dynamicalr-process heating makes the light curve brighter and bluer atpost-merger. However, the high-velocity tail of the ejecta distribution and the early () light curves are largely unaffected.