论文标题
厚盘的星系模型和相等质量星系对碰撞的模拟
A thick-disk galaxy model and simulations of equal-mass galaxy pair collisions
论文作者
论文摘要
我们实施了文献中报道的数值模型，以模拟由四个物质组成部分组成的星系的演变，例如：深色halo；旋转的恒星盘；恒星的球形凸起和一个分子气环。我们表明，对于10 Gyr（Gyr = $ 10^{9} $年），该星系模型的演变至少稳定。我们通过圆形速度和角动量分布的数字来表征该星系模型的结果构型。速度的切向和径向成分；峰密度演化和径向密度曲线。此外，我们计算了几种相等的质量星系二进制碰撞的模型，例如：（i）额叶和（ii）倾斜（带有撞击参数），（iii）两个模型，其初始条件是从2体轨道上获取的，以及（iv）非常接近的通道。为了与星系模型进行比较，我们以类似的方式表征了碰撞模型的动力学。最后，对于所有碰撞模型的径向尺度为0-100 kpc，我们确定径向密度曲线的de vaucouler拟合曲线，而与预碰撞轨迹无关。为了以较小的径向尺度（0-20 kpc）研究径向质量密度和径向表面密度曲线，我们使用四参数拟合曲线。
We implement a numerical model reported in the literature to simulate the evolution of a galaxy composed of four matter components, such as: a dark-matter halo; a rotating disk of stars; a spherical bulge of stars and a ring of molecular gas. We show that the evolution of this galaxy model is stable at least for 10 Gyr (Gyr=$10^{9}$ years). We characterize the resulting configuration of this galaxy model by figures of the circular velocity and angular momentum distribution; the tangential and radial components of the velocity; the peak density evolution and the radial density profile. Additionally, we calculate several models of equal-mass galaxy binary collisions, such as: (i) frontal and (ii) oblique (with an impact parameter), (iii) two models with initial conditions taken from a 2-body orbits and (iv) a very close passage. To allow comparison with the galaxy model, we characterize the dynamics of the collision models in an analogous way. Finally, we determine the de Vaucouleurs fitting curves of the radial density profile, on a radial scale of 0-100 kpc, for all the collision models irrespective of the pre-collision trajectory. To study the radial mass density and radial surface density profiles at a smaller radial scale, 0-20 kpc, we use a four-parameters fitting curve.
