标题： 暗物质晕的速度矩 显示英文标题

标题： Velocity moments of dark matter haloes

摘要： 利用宇宙N体模拟，我们研究了暗物质晕的视线速度分布，重点关注最低阶的偶数矩——弥散度和峰度及其在估算宇宙结构质量分布中的应用。 对于从模拟盒子中选出的十个大质量晕中的每一个，我们确定了其视在质量、浓度以及各向异性参数。 为了模拟每个晕的观测结果，我们随机选择300个粒子，并分别沿视线方向和天空表面投影它们的速度和位置。 在去除闯入者后，我们计算视线速度矩的分布并用Jeans方程的解来拟合它们。 通过这种方法得到的视在质量、浓度参数和速度各向异性估计值与从完整三维分析中获得的值非常一致。 显示英文摘要

摘要： Using cosmological N-body simulations we study the line-of-sight velocity distribution of dark matter haloes focusing on the lowest-order even moments, dispersion and kurtosis, and their application to estimate the mass profiles of cosmological structures. For each of the ten massive haloes selected from the simulation box we determine the virial mass, concentration and the anisotropy parameter. In order to emulate observations from each halo we choose randomly 300 particles and project their velocities and positions along the line of sight and on the surface of the sky, respectively. After removing interlopers we calculate the profiles of the line-of-sight velocity moments and fit them with the solutions of the Jeans equations. The estimates of virial mass, concentration parameter and velocity anisotropy obtained in this way are in good agreement with the values found from the full 3D analysis.