Radiation hydrodynamics modelling of kilonovae with SNEC
Radiation hydrodynamics modelling of kilonovae with SNEC
复制标题
使用 SNEC 进行千新星辐射流体动力学建模
DOI：
10.1093/mnras/stac399
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发表时间：
2022
影响因子：
4.8
通讯作者：
Radice, David
中科院分区：
文献类型：
--
作者：
Wu, Zhenyu;Ricigliano, Giacomo;Kashyap, Rahul;Perego, Albino;Radice, David
我们开发了一种方法来计算合成kilonova光变曲线，结合联合收割机数值相对论模拟的中子星星合并和SNEC辐射流体动力学代码。我们描述了我们的实施初始和边界条件，r-过程加热，和不透明的kilonova模拟。我们验证我们的方法，仔细检查，能量守恒是满意的，并通过比较theSNEC结果与两个半解析光曲线模型。我们应用我们的代码来计算三个二进制具有不同的质量比（平等和不平等的质量）和不同的合并结果（短寿命和长寿命的残余物）的彩色光变曲线。我们研究了我们的结果的敏感性，流体动力学效应，核物理不确定性的加热速率，并合并模拟的持续时间。我们发现，流体力学的影响通常是可以忽略不计的，在大多数情况下，同源膨胀是一个很好的近似。然而，压力可以放大放射性加热率的不确定性的影响。我们还研究了冲击可能发射到外流的相对论射流的影响。我们的模型都不匹配AT 2017 gfo，GW 170817中的kilonova。这指出了我们的合并模拟和kilonova模型中可能存在的缺陷，这些模型忽略了非LTE效应和合并残余物可能带来的额外能量注入，并且需要超越这项工作中采用的球对称假设。
We develop a method to compute synthetic kilonova light curves that combine numerical relativity simulations of neutron star mergers and theSNECradiation–hydrodynamics code. We describe our implementation of initial and boundary conditions, r-process heating, and opacities for kilonova simulations. We validate our approach by carefully checking that energy conservation is satisfied and by comparing theSNECresults with those of two semi-analytic light-curve models. We apply our code to the calculation of colour light curves for three binaries having different mass ratios (equal and unequal mass) and different merger outcome (short-lived and long-lived remnants). We study the sensitivity of our results to hydrodynamic effects, nuclear physics uncertainties in the heating rates, and duration of the merger simulations. We find that hydrodynamics effects are typically negligible and that homologous expansion is a good approximation in most cases. However, pressure forces can amplify the impact of uncertainties in the radioactive heating rates. We also study the impact of shocks possibly launched into the outflows by a relativistic jet. None of our models match AT2017gfo, the kilonova in GW170817. This points to possible deficiencies in our merger simulations and kilonova models that neglect non-LTE effects and possible additional energy injection from the merger remnant and to the need to go beyond the assumption of spherical symmetry adopted in this work.