论文标题
Fornax Dwarf Galaxy的N体自洽星 - 恒星建模
N-body self-consistent stars-halo modeling of the Fornax dwarf galaxy
论文作者
论文摘要
我们介绍了与银河系相关的Fornax矮人球形星系的几乎自以为是的恒星 - 挂车模型。这样的星系以暗物质为主，并且系统中几乎没有气体。因此，它们是N体建模的出色对象，考虑到可见和暗物质的光环成分。为了根据对Fornax恒星的测量速度分析推断出的暗物质光环，我们基于两个源代码集构建了几个自一致的准平衡模型。其中之一（银河系软件，NEMO）处理的是自洽的分布功能建模，该建模取决于能量$ e $和Angular Momentum $ L_Z $的垂直组件。另一个包含在Agama框架中，并基于Schwarzschild的轨道计算。它可以重现Fornax的非球形自洽结构，因为即使推断的深色光环参数来自牛仔裤分析，即使不要求任何分布函数应为正式轨道分析。为了猜测使N体模型接近可见对象的参数，我们根据流体动力轴对称牛仔裤方程使用了Fornax Galaxy的恒星 - 漆黑物质模型，并考虑了速度各向异性参数。然后，我们通过使用猎鹰代码进行N体模拟来研究模型的演变，以测试其稳定性。随着时间的推移，模型参数的可变性是在模拟过程中获得的。 AGAMA模型显示了与观察到的数据相结合的速度分散曲线的最佳一致性。
We present nearly self-consistent stellar-halo models of the Fornax dwarf spheroidal galaxy associated with the Milky Way galaxy. Such galaxies are dominated by dark matter and have almost no gas in the system. Therefore, they are excellent objects for N-body modeling that takes into account visible and dark matter halo components. In order to model the dark matter halo inferred from the analysis of the measured velocities of Fornax's stars, we constructed several self-consistent quasi-equilibrium models based on two source code sets. One of them (GalactICS Software, NEMO) deals with the self-consistent distribution function modeling which depends on energy $E$ and vertical component of the angular momentum $L_z$. The other is included in the AGAMA framework and is based on Schwarzschild's calculation of orbits. It can reproduce the non-spherical self-consistent structure of Fornax as the weighted sum of orbit contributions to the galactic density even though the inferred dark halo parameters come from Jeans analysis which does not require that any distribution functions should be positive. To guess the parameters which make the N-body models close to the visible object we use the stellar-dark matter model of the Fornax galaxy based on hydrodynamic axisymmetric Jeans equations taking into account the velocity anisotropy parameter. Then we studied the evolution of the models by performing N-body simulations with the falcON code in order to test their stability. The variability of the model parameters over time was obtained during simulations. The AGAMA models show the best agreement of the resulting velocity dispersion profiles with the observed data.
