论文标题
早期星系的基本平面对年龄和内部结构的依赖性
Dependence of the Fundamental Plane of Early-type Galaxies on Age and Internal Structure
论文作者
论文摘要
我们研究了早期型星系（ETG）的基本平面（FP）及其对ETG的年龄和内部结构的依赖，使用$ 16,283 $ ETG，$ M_R \ le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-le-l <0.055 $ <0.055 $ in Sloan数字天空调查数据。我们使用ETG年龄与光度参数（例如颜色，绝对幅度和中央速度分散）之间的关系，发现FP中的散射取决于年龄。年龄$ \ gtrsim9 $ gyrs的旧ETG的FP较小的散布$ \ sim0.06 $ dex（$ \ sim14 \％\％$），而年轻的eTgs aff agy $ \ lyssim6 $ gyrs的零散零散的零散较大$ \ sim0.075 $ dex（$ \ sim17 \ sim17 \％$ \％）。就年轻的ETG而言，较少的紧凑型ETG在FP中的散布较小（$ \ sim0.065 $ dex; $ \ sim15 \％$），而不是更紧凑的eTG（$ \ sim0.10.10 $ dex; $ \ sim23 \％$）。另一方面，旧ETG的FP中的散射不取决于星系结构的紧凑性。因此，在ETG的亚群中，紧凑的年轻ETG在FP中具有最大的散射。紧凑的年轻ETG中的这种大散射是由具有低动力学质量与光比（$ M_ \ mathrm {dyn}/l $）和中央区域的蓝色的ETG引起的。通过与经历过富含气体的主要合并的星系的简单模型进行比较，我们发现最近富含气体的主要合并的场景可以合理地解释给定质量过多的光线（低$ M_ \ MATHRM {dyn}/l $）和蓝色中心色的紧凑型ETG的特性。
We investigate the scatter in the fundamental plane (FP) of early-type galaxies (ETGs) and its dependence on age and internal structure of ETGs, using $16,283$ ETGs with $M_r\le-19.5$ and $0.025\le z<0.055$ in Sloan Digital Sky Survey data. We use the relation between the age of ETGs and photometric parameters such as color, absolute magnitude, and central velocity dispersion of ETGs and find that the scatter in the FP depends on age. The FP of old ETGs with age $\gtrsim9$ Gyrs has a smaller scatter of $\sim0.06$ dex ($\sim14\%$) while that of young ETGs with age $\lesssim6$ Gyrs has a larger scatter of $\sim0.075$ dex ($\sim17\%$). In the case of young ETGs, less compact ETGs have a smaller scatter in the FP ($\sim0.065$ dex; $\sim15\%$) than more compact ones ($\sim0.10$ dex; $\sim23\%$). On the other hand, the scatter in the FP of old ETGs does not depend on the compactness of galaxy structure. Thus, among the subpopulations of ETGs, compact young ETGs have the largest scatter in the FP. This large scatter in compact young ETGs is caused by ETGs that have low dynamical mass-to-light ratio ($M_\mathrm{dyn}/L$) and blue color in the central regions. By comparing with a simple model of the galaxy that has experienced a gas-rich major merger, we find that the scenario of recent gas-rich major merger can reasonably explain the properties of the compact young ETGs with excessive light for a given mass (low $M_\mathrm{dyn}/L$) and blue central color.
