论文标题
重新审视低质量星系的球状簇数量和星系质量的关系
Revisiting the relation between the number of globular clusters and galaxy mass for low mass galaxies
论文作者
论文摘要
使用一种新方法来估计总星系质量（m $ _ {\ rm t} $）和两个低光度星系的样本，其中包含每个星系的球状簇数（GCS）的测量（n $ _ {\ rm gc} $）使用总共203个星系，其中157个具有m $ _ {\ rm t} $ $ \ \ \ le 10^{10} $ m $ _ \ odot $。我们发现关系几乎是线性的，n $ _ {\ rm gc} \ propto $ m $ _ {\ rm t}^{0.92 \ pm0.08} $将至少为m $ _ {\ rm t} \ sim t} \ sim 10^{8.75} $ m $ m $ $ _ \ osot $ _ \ odot $ odot $。由于该关系扩展到平均每个星系少于一个GC的星系，并扩展到合并相对较少的质量范围，因此该关系不能仅仅是层次星系形成的新兴特性。低质量星系中径向GC分布的特征，以及在这些星系质量上缺乏合并的特征，似乎也挑战了中央，耗散浓缩的高密度，高压区域中的GCS形成的模型，然后散布到大半径上。拟合的幂律指数与一个值的略有差异，为浅M $ _ {\ rm t} $的空间留出空间 - 平均质量的依赖性变化，这将允许GCS中的总质量与M $ _ {\ rm T} $之间的关系。
Using a new method to estimate total galaxy mass (M$_{\rm T}$) and two samples of low luminosity galaxies containing measurements of the number of globular clusters (GCs) per galaxy (N$_{\rm GC}$), we revisit the N$_{\rm GC}-$M$_{\rm T}$ relation using a total of 203 galaxies, 157 of which have M$_{\rm T}$ $\ \le 10^{10}$ M$_\odot$. We find that the relation is nearly linear, N$_{\rm GC} \propto$ M$_{\rm T}^{0.92\pm0.08}$ down to at least M$_{\rm T} \sim 10^{8.75}$ M$_\odot$. Because the relationship extends to galaxies that average less than one GC per galaxy and to a mass range in which mergers are relatively rare, the relationship cannot be solely an emergent property of hierarchical galaxy formation. The character of the radial GC distribution in low mass galaxies, and the lack of mergers at these galaxy masses, also appears to challenge models in which the GCs form in central, dissipatively concentrated high-density, high-pressure regions and are then scattered to large radius. The slight difference between the fitted power-law exponent and a value of one, leaves room for a shallow M$_{\rm T}$-dependent variation in the mean mass per GC that would allow the relation between total mass in GCs and M$_{\rm T}$ to be linear.
