论文标题
M82的中级磁盘超级明星簇的质量 - 拉迪乌斯关系
Mass-radius relation of intermediate-age disk super star clusters of M82
论文作者
论文摘要
我们为M82磁盘中的99个中级超级星团（SSC）样本提供了一组完整的结构参数，并使用半分析群集进化代码emacss进行了生存分析。这些参数基于先前工作中进行的轮廓拟合分析，其质量相关量使用质量与光比的量比为100 MYR的质量与光比。 SSC遵循具有索引$α$ = 1.5的幂律质量函数，并且具有典型半光线半径的对数正态大小函数，RH = 4.3 PC，两者都与麦哲伦云中簇的值相当，而不是巨型螺旋形。大多数SSC遵循幂律质量 - 拉迪乌斯关系，其索引为b = 0.29 $ {\ pm} $ 0.05。使用EMACS对M82 SSC进行的动态分析表明，23％的簇是潮汐限制的，目前其余的簇正在膨胀。这些集群的正向演变表明，大多数将溶解在〜2 Gyr中。然而，发现一组四个巨大的紧凑型簇和另一组在相对较大的中心距离处的五个SSC，可以在哈勃时期存活。模型预测的质量，RH，$ {μ_v} $和在12 GYR处的这些幸存的SSC的核心半径与银河系球形簇样品的相应值可比。
We present a complete set of structural parameters for a sample of 99 intermediate-age Super Star Cluster (SSCs) in the disk of M82, and carry out a survival analysis using the semi-analytical cluster evolution code EMACSS. The parameters are based on the profile-fitting analysis carried out in a previous work, with the mass-related quantities derived using a mass-to-light ratio for a constant age of 100 Myr. The SSCs follow a power-law mass function with an index $α$=1.5, and a log-normal size function with a typical half-light radius, Rh=4.3 pc, which are both comparable with the values for clusters in the Magellanic Clouds, rather than in giant spirals. The majority of the SSCs follow a power-law mass-radius relation with an index of b=0.29${\pm}$0.05. A dynamical analysis of M82 SSCs using EMACSS suggests that 23% of the clusters are tidally-limited, with the rest undergoing expansion at present. Forward evolution of these clusters suggests that the majority would dissolve in ~2 Gyr. However, a group of four massive compact clusters, and another group of five SSCs at relatively large galactocentric distances, are found to survive for a Hubble time. The model-predicted mass, Rh, ${μ_V}$ and core radius of these surviving SSCs at 12 Gyr are comparable with the corresponding values for the sample of Galactic globular clusters.
