论文标题
机翼簇的结构和动态建模。 iii。伪相空间密度曲线
Structural and dynamical modeling of WINGS clusters. III. The pseudo phase-space density profile
论文作者
论文摘要
数值模拟表明，宇宙晕圈显示伪相空间密度（PPSD）的幂律径向谱，q = rho/sigma^3，其中Rho是质量密度和Sigma速度分散体。我们使用从MAMPOSST代码进行的Markov Chain Monte Carlo（MCMC）分析中得出的参数测试这些预测，该参数是在基于速度分散的堆栈（SIGMAV）的观察到的基于翅膀数据集的Galaxies常规星系群的基于速度分散的堆栈（SIGMAV）的运动学。在PPSD的定义中，密度在总体Rho（Q_RHO）中，或者在星系中的星系密度NU（Q_NU）中，三个形态学类别的星系（椭圆形，衬里和螺旋）的形态学类别（而速度分散）（通过总和的汇总或汇总）是汇总或汇总（Q_N） （q_r，rho和q_r，nu）。我们发现PPSD配置文件是几乎所有MCMC参数的幂律关系。我们观察到的Q_RHO（R）和Q_R，用于椭圆形和螺旋的Rho（R）的对数斜率与模拟中粒子的预测非常吻合，但S0s略浅。对于q_nu（r）和q_r，nu（r），只有椭圆形的ppsd斜率匹配模拟中粒子的颗粒，而螺旋的斜率很浅，类似于Subhalos的斜率。但是，对于基于丰富度或气温的集群堆栈，幂律PPSD的比例较低（尤其是Q_NU），除S0S外，Q_RHO斜率较浅。使用Rho而不是NU定义的观察到的PPSD轮廓似乎是星系簇的基本特性。它们将在暗物质和椭圆形的剧烈放松阶段印记，然后在螺旋螺旋中朝着集群重力电位的动态平衡时进行烙印，而S0S则是中间的（富度和基于温度的堆栈）或混合类（SIGMAV堆栈）。
Numerical simulations indicate that cosmological halos display power-law radial profiles of pseudo phase-space density (PPSD), Q=rho/sigma^3, where rho is mass density and sigma velocity dispersion. We test these predictions using the parameters derived from the Markov Chain Monte Carlo (MCMC) analysis performed with the MAMPOSSt code on the observed kinematics of a velocity dispersion based stack (sigmav) of 54 nearby regular clusters of galaxies from the WINGS dataset. In the definition of PPSD, the density is either in total mass rho (Q_rho) or in galaxy number density nu (Q_nu) of three morphological classes of galaxies (ellipticals, lenticulars, and spirals), while the velocity dispersion (obtained by inversion of the Jeans equation) is either the total (Q_rho and Q_nu) or its radial component (Q_r,rho and Q_r,nu). We find that the PPSD profiles are power-law relations for nearly all MCMC parameters. The logarithmic slopes of our observed Q_rho(r) and Q_r,rho(r) for ellipticals and spirals are in excellent agreement with the predictions for particles in simulations, but slightly shallower for S0s. For Q_nu(r) and Q_r,nu(r), only the ellipticals have a PPSD slope matching that of particles in simulations, while the slope for spirals is much shallower, similar to that of subhalos. But for cluster stacks based on richness or gas temperature, the fraction of power-law PPSDs is lower (esp. Q_nu) and the Q_rho slopes are shallower, except for S0s. The observed PPSD profiles, defined using rho rather than nu, appear to be a fundamental property of galaxy clusters. They would be imprinted during an early phase of violent relaxation for dark matter and ellipticals, and later for spirals as they move towards dynamical equilibrium in the cluster gravitational potential, while S0s are either intermediate (richness and temperature-based stacks) or a mixed class (sigmav stack).
