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 = 10⁹ 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 orbit 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-parameter fitting curve.

我们实施了文献中报道的数值模型来模拟由四种物质成分组成的星系的演化，例如：暗物质晕；一个旋转的恒星盘；一个球形凸起的恒星和一圈分子气体。我们证明这个星系模型的演化至少在 10 Gyr (Gyr = 10 ⁹年）。我们通过圆速度和角动量分布图来描述这个星系模型的结果配置；速度的切向和径向分量；峰值密度演变和径向密度分布。此外，我们计算了几个等质量星系二元碰撞模型，例如：（i）正面和（ii）倾斜（带有撞击参数），（iii）初始条件取自两体轨道的两个模型和（ iv) 一段非常接近的段落。为了与星系模型进行比较，我们以类似的方式描述了碰撞模型的动力学特征。最后，我们确定所有碰撞模型的径向密度分布的 de Vaucouleurs 拟合曲线，径向尺度为 0-100 kpc，与预碰撞轨迹无关。